Swr directional coupler

They couple a defined amount of the electromagnetic power in a transmission line to a port enabling the signal to be used in another circuit. 4 GHz, see W1GHZ descriptions in his paper. (ERI) will show a new series of adjustable directional couplers that feature external terminations. Microstripline SWR pickup: question regarding working mechanism - Page 1 Whether you use a bridge or directional coupler, you are ending up doing the same thing. '/4 db, and SWR of  The SWR sensor. The 3151-10 from L3 Narda-MITEQ is a Directional Coupler with Frequency 820 to 980 MHz, Coupling 10 dB, Coupling Variation ±1 dB, Frequency Sensitivity ±0. Attenuators (pads) For 1kW operation this means the termination (which in this case is also an attenuator) should be able to handle 1W. It can be manually selected from the front panel, or the meter can automatically sense whichever coupler is receiving power and display it. Directional coupler 150MHz. Includes Collins 542-4116-004 directional coupler, 458-0388-00 3" square wattmeters, phenolic rotary switch with knob to select meter scale and a ceramic rotary switch to select an antenna or dummyload. This is a revised version of the original design below using SMT parts. Directional Coupler 20dB The X3C09F1-20S is a low profile, high performance 20dB directional coupler in a new easy to use, manufacturing friendly surface mount package. M 3. 36) that has a US patent in 1969 by Sontheimer and Fredrick 2. MCLI couplers are offered in both directional and dual directional with many low frequency and high power solutions utilizing both stripline and lumped element technology. This samples a small amount of power in one direction and then uses a diode to rectify this after which it is  Directional coupler. SWR, LP rigid coax couplers are constructed of heavy-wall copper, PTFE insulators, and silver plated inner connectors. Buy Coax Directional Coupler at a great price or buy in bulk and save even more. com SYSTEMS WITH RELIABILITY, LP. A second switch sets the averaging time for the AEP calculation. Directional coupler and detector diodes from a Motorola cellular phone. 3. They are seldom used with a transmitter or remain connected to an antenna for the long-term. Directional Coupler is a 4-port waveguide junction consisting of a primary main waveguide and a secondary Couplers. We used it to look at the source and reflected waves, and so find the reflection coefficient etc. These items are for diy hobbyists collectors only. I am using a dual directional coupler that supplies a voltage relative to the RF power. 08 Max. Unfortunately, I can not find any off the shelf component to fit this frequency range. SWR Bridges. Although the coupled-port return loss is lower than that of the TCD model, for most applications this return loss performance is not important. Interestingly, 1/4 wave couplers (microstrip or stripline or the like) give the same coupling at 3/4 wavein other words, at the third harmonic, which is useful for 146MHz and 440MHz. [Read: ERI Ups Benco to VP of U. The accuracy is due to dimensional tolerances that can be held for the spacing of the two coupled lines. If we put two waveguides or microstrip lines (or PCB traces) carrying rf signals close enough to each other, some of the evanascent wave in the transverse direction (orthogonal to the line) will overlap with the propagating mode of the other line, The SWR bridges or SWR meters are based around what is termed a directional coupler. 281 volts My question is how do I use this? However, a circuit based on log amps and a directional coupler that detects the voltage standing-wave ratio (VSWR) of the resulting standing wave can be used to trigger protection of the PA from excessive VSWR values. 4 GHz), or by pairing your BB60C spectrum analyzer with this coupler a USB-TG124A (up to 6 GHz). • It is possible to have a low VSWR and an antenna system that is a poor radiator. This will solve the SWR problem, and because the directional coupler will sit between the amplifier output and the low-pass filters, The dual coupler option consists of a daughtercard which plugs into an RF header on the main LP-100A PCB. Main Line SWR:- The main line SWR is the standing wave ratio measured looking into the main line input terminals when matched loads are placed at all the other terminals. SW-200. Ports 3 and 4 may even have smaller connectors to distinguish them from the main line ports of the RF coupler. I think it was about 1m long, and the signal was a 10MHz sine wave. Power 1000-2000W Size 120 x 50 mm. While the directional bridge has a coupled port, the swr bridge has a 'reflected power' port. We use cookies to improve user experience. Create a scalar network analyzer (SNA) for measuring return loss by pairing your USB-SA44B spectrum analyzer with this coupler and a USB-TG44A (up to 4. If you want to use the directional coupler for SWR protection, you may reverse   A directional SWR meter measures the magnitude of the each one individually, with directional couplers. This coaxial dual directional coupler has a frequency range extending over four octaves from 100 MHz to 2 GHz. Secondary = 1. The configuration used in the Directional coupler works well over  reflected power with the SWR displayed on wattmeter. A Bruene Bridge Directional Coupler with DC Output (V2) A Bruene Bridge Directional Coupler with Direct RF Output; The Amplifier Module Gallery. The 4-port directional coupler The other point mentioned by others and IBC is that the higher value directional couplers give more accurate results. Diagram of a typical coaxial directional coupler Figure 2. High Directivity Directional Couplers Andrew Directional Couplers. standards for reliability, performance and quality. It is built into a "Whitmans Sampler" candy tin. NSN: 6625-01-129-1892. Directional couplers in their auxiliary arms sample the power flowing in one direction in the mainline and ignore power flowing in the opposite direction. On 15 Jun 2015 @CommScope tweeted: "Learn about #PIM and #VSWR fundamentals . Directional coupler and detector diodes from a Toshiba cellular phone. 5 dB coupling at the frequency band centre. This page covers rf directional coupler basics and provide rf directional coupler manufacturers. LAGASSE Laboratory of Electromagnetism and Acoustics, University of Ghent, Belgium (Received 13 July 1970) The design and realization of an acoustical directional coupler are presented. For UHF - SHF, up-to 2. The bottom half of the circuit seems pretty straightforward. One toggle switch determines whether forward or load powers are displayed. Obviously, a lower resistance reflects an inverted wave. A large VSWR can cause many problems in RF circuits. Likewise, there is a standing wave pattern of the forward and reflected currents . A reflectometer bridge is a set of two impedance bridges; one used normally, and one used with the generator and the load transposed. Directional coupler is used to decouple a piece of energy from incident and reflected wave. Installation location of the antenna, surrounding buildings and so on, can also be a cause of high swr value. SWR meters are often using a 6-port coupler, because it's directivity is nearly unaffected by mismatching of the detector outputs. If swr is too high If swr of the antenna is too high, see if antenna is correctly assembled and soldered, or coaxial cable and connector are correctly assembled and soldered. . SWR stands for “standing wave ratio” and is a measure that can be used to tune an antenna for a particular frequency. somewhat physically compact directional coupler SWR / directional watt-meter designs? I'm also looking for equations or quantitative design parameters relating to their design and operation. Both of these couplers are not suitable for 23cm. Gerbers AA Directional Coupler_03162018. There is a way to do good measurements using a directional coupler. Suppose you make a measurement with dual directional coupler terminated with a short, the coupler has the following parameters coupling-20dB, directivity 30dB, Pin = 1mw incident on port 1. M 1. 773D Directional Coupler The 773D directional coupler is a three port passive device. pdf Yantel directional coupler is a low profile, low cost high performance surface mounted device. 3,426,298 Feb 4 1969 From W1FB: “An SWR bridge circuit appeared in the winter 1989/1990 edition of SPRAT, the ham journal of the GQRP club. Attenuation measurement, reflectometer setup, power measuring, source levelling and network analysis are just a few areas in which couplers are used. C $93. Specification of Directional Coupler. Coupler Alternatives The firmware can be modified or extended to just about any kind of directional coupler that generates two DC output voltages, one for forward power, and the other for reflected power; or to a sensor that has a single DC output voltage corresponding to actual SWR. SYSTEMS WITH RELIABILITY, LP. Enlarge Image. The coupler of Figure 10-38 is the waveguide analog of the transmission-line coupler of Figure 7-19. 15 (secondary) Connectors: Type N; Shipping weight: 5 lb Measurements of 1mW have been omitted, but the coupler has been optimized to over 2kW, thus ideally suited for power amplifiers. 00. 5. operating power, coupling 15-20dB). A true directional coupler for increased accuracy gives solid readings over the entire frequency range, HF to UHF. It can be seen that the SWR meter consists of three main parts: directional coupler, two detectors and display unit. You may want to replace the meter's existing RF bypass Capacitors with higher quality (mica) ones. Clean all connectors with a lint free swab and IPA. A reflectometer-type SWR meter can be calibrated to give power back and forth (PF, Pr) on a power supply. These directional couplers sample a small amount of the power passing in one direction, and this can be used to provide an indication of the power in this direction. Power Input Max. The dual coupler option adds a pair of connectors to the rear panel of the LP-100A to allow for connection of a second coupler. Stripline SWR Meter Another weekend project that I made is this SWR (Standing Wave Ratio) meter which rf pick-up is a directional coupler fabricated from microstrip. Narda 3022 Dual Directional Coupler, 1. Coupling factor: Measure of the amount of signal coupled to the output port. Since I wrote the post about the RF SWR & Power meter, I’ve been meaning to get around to a redesign of the board with a built-in directional coupler, and that time has finally come. 8 to 160 MHz, while the other covers 430 to 1300 MHz in three bands. Directional coupler and detector diode from another Toshiba cellular phone. Another great W2AEW video. SWR of DUT is out of specs and i believe that the problem is the adapters i use. 4, Input Power Rating is  27 Feb 2019 Most SWR meters use directional couplers. Keysight 8474B,C,E detectors offer excellent broad-band frequency response and low SWR for this application. VSWR (:1) Typ. Note the large forward spikes with only small reverse spikes. Specification Frequency Range (MHz) 698 – 2700; Coupling(db) 20 1. In some critical applications such as a system test, the coupler's standing wave ratio (SWR) is also a factor, as these reflections travel back and forth internally and will add to, or subtract from, the power levels of the signal of interest. Meter accuracy is +/- 10% of full scale or better. They then control how much power is allocated to each area depending upon the coverage needed. 6 GHz directional coupler. Characterize return loss / impedance matching / VSWR; Measure output power and reflection in real SWR Bridge is a special case of Directional Coupler. A Battery Operated Low Noise Low Frequency FET Amplifier; A Complementary HF Push-Pull Amplifier; A Quad JFET HF Amplifier; A Resistive Feedback HF Amplifier with Lowpass Filter Measurements of this directional coupler on 50 ohms system (50 ohms source, 50 ohms load): Results with 450 MHz antenna: End results. 0 to 4. The directional coupler design is classic and well known. SWR, Return Loss, and Reflection Coefficient. The Keysight 87301E coaxial directional coupler, 2 GHz to 50 GHz, is designed for signal monitoring and is supplied with 2. New, unused  Dual Directional Coupler 502020030 Outline Drawing 14 dB (2-12. The power measurements include incident power, reflected power, VSWR values, etc. It was pulled out of decommissioned HF-8023 solid state linear amplifier 1KW and it is in excellent condition. I use dual directional coupler, power meter or crystal detector to measure forward and reflected power and waveguide to N adapters X281aA. Turning back to Fig 1, Standing Wave Ratio is fundamentally defined as the ratio between the maximum and minimum voltages anywhere along the line. 2 Directional Coupler A directional coupler is a four-port network in which portions of the KD1JV Digital SWR / Power Meter. 619 Industrial Park Road Ebensburg, PA 15931 PHONE 814-472-5436 FAX 814-472-5552 EMAIL davide@swr-rf. VSWR is defined as the ratio of the maximum voltage to the minimum voltage in standing wave pattern along the length of a transmission line structure. Stockton, G4ZNQ. The coupling, return loss and power handling is great. Hi, I've been looking at DIYing some sort of VNA for antenna measurements, and see "directional coupler", "return loss bridge" and "swr bridge" used interchangeably in internet articles. Make sure to remove any contamination, dirt, or metallic flakes in and around mating surfaces. 33 volts). Narda coaxial directional coupler. 15 (primary) 1. 0 out of 5 stars 1 $11. The X3C09F1-20S is designed particularly for balanced power and low noise amplifiers, plus signal distribution and Power enters the filter system through a directional coupler consisting of current transformer T2, capacitors C36-38, C40-42, and resistors R4, 5 and 6. 796/3, shown at left and in schematic form above, has high directivity, insertion loss of only about. SWR Sensor (from 2010 ARRL Antenna Handbook) At 100 watts, IFWDOUT (into a short) > 6 mA At 100 watts, VFWDOUT (into an open) > 2. This sampled RF signal is rectified and drives a meter or other indicating device. What is a Bidirectional Coupler. We Sell WISP Networking and Infrastructure Equipment including Towers, Masts, brackets, Mounts, Antennas, Amplifers, Coaxial Cable, Wire and hardware at 1-877-660-0951 the coupler can be conveniently converted to other types of connectors by use of an adapter, Adapters are available to OSM, TNC, GR900, and others, so that the coupler becomes a versatile device for making measurements on many different types of connector configurations. 4000 MHz. A50 PCB has desidned for 70cm for the same power range. The metering system uses a directional coupler to sample the reflected and forward signals at the output of the transmitter. You would expect there to be losses according to the -20 db taps (one forward and one reverse). This series products are suitable for AMPS, DCS, PCS, UMTs & 3G band applications. 2. The small picture shows a 6-port coupler, the large a standard 4-port. SWR Meters and coupler PCB's at WIMO. RFDC4M3G10 Trc1 S11 SWR 100 mU/ Ref 1 U Cal. Later found out it is very similar Contra-directional Coupler Scroll Prev Top Next More In this example, we will study the performance of an electrically tunable contra-directional coupler (CDC) using CHARGE (electrical simulation) and MODE (optical simulation). " - read what others are saying and join the conversation. A classic example is the 1943 Bird Series power meter, which is a directional coupler is used to obtain a sample voltage proportional to the voltage wave or forward or backward on the feeder (VF, VR). How a directional coupler in an SWR meter works. Directional Coupler USEFUL TOOLS Basically directional coupler is a 4 ports device (port1 - input, port2 -transmitted, port3 - coupled, port4 -isolated), which has many uses in HF technik (forward and reflected power measurement, automatic level control, etc. Mike was using return loss as a way to monitor SWR on an antenna, using a dual directional coupler. dB Directional Coupler 1 GHz Single port Tap Off T Style F Coaxial 5 - 1000 MHz 75 Ohm 2-Way Directional Coupler Signal Splitter Back Cover Printed Circuit Board 5. 6). VSWR is a measure of impedance mismatches in a circuit. COUPLING FACTOR: Directional couplers are specified in terms of the coupling accuracy at the frequency band centre. TV antenna splitters are designed to work with 75 ohms impedance level. LCD SWR PEP/AVG power meter indicator for LDMOS MOSFET tube amplifier The device is designed to display on the LCD alphanumeric display the values of the forward power and VSWR . From Microstrip or stripline couplers are backward wave couplers because they rely on coupled lines: for a signal incident on port 1, port 4 is the coupled port (port 3 is isolated in our clockwise notation). Review (mpn: 250-24 for sale) 250-24 Box Swr Johnson Viking Directional Ef Bridge Coupler Original 52 Tube testing all auction tubes are tested on one of several testers our main tester is a dan nelson calibrated tv 7d No other forms of payment are accepted for local pick up. Fully portable and self contained, it delivers a wide range of basic and advanced RF measurements to present a complete picture of your antenna systems and networks. If you want to build a meter with more power range than the Two Hole Directional Coupler:. If you want to build a meter with more power range than the one shown here, you will need a higher-power coupler. We are a registered corporation within california look us up. This auction is for a single Collins directional coupler. Depending on the frequency range, coupling loss becomes less Theoutput return loss is measured by applying a test signal to the oscillator through a directional coupler or circulator: Any reflected energy appears at the test port and will be x dB below the input. “ 1-W1FB’s Design Notebook, Page pg 173 2-Patent No. SW3a simply goes to a dummy load during calibration. Connect the RF coupler coupled (CPL) connection to the RF Input of the DSA. Accuracy of the readings is assured because the PM2000A features a true shielded directional coupler. 0 vdc Any small signal diode will work (Germaniums are best for QRP) Shield on coax used as a Faraday shield (grounded on one end only) Tandem Match Coupler 5/4/2012 Another important Directional Coupler parameter is Directivity. Here is a good TV antenna signal splitter I used: Theoretically the signal splitter should provide around 20 dB of signal output port to another when the “input” port is terminated with nominal impedance (75 ohms). A Directional coupler is a device that samples a small amount of Microwave power for measurement purposes. The cross directional coupler is a special type of directional coupler. 1. Typically specified in dB: Input power: Amount of power that can be applied to the input. We also use the hickok 799 and b k when an item is sold as is this means, what you see is what you get. Select the 1. Source: Bogdan. com. Flatness specifies the maximum coupling variation within the coupling range. Depending on the Directional Coupler design, you may need another cable or adapter to connect it to the DSA. This unit can be used as power meter and SWR meter for 28MHz to 435MHz. COM Playing with S-parameters and the Smith chart in Qucs The CP1 directional coupler is not entirely transparent and raises the SWR by a bit as signal passes through it. I removed the upper insulation and braid from piece of RG316 coax cable. The Comba DC-FR13-ON300C(I) is a 340-2700 MHz 13dB directional coupler with N female connectors. We had spectrum analyzers connected to both the forward and reflected ports, and were monitoring the difference between forward and reverse ports. However, as it can be seen from Figure 1 directional coupler has an important parameter, length. SWR less than 1. Most HF transceivers and antenna tuners have built in SWR meters. This directional coupler detects termination errors at the filter’s power amplifier side. The multi-octave capability makes measurements easier–setup and calibration time are reduced, since normally several couplers are required over this frequency band. The reason is that directional couplers are frequently used for load-pull testing of amplifiers or monitoring a signal after a power amplifier. of a wavelength, the performance of the 30-dB directional coupler, the output directional  Bird 8329-300 เป็นตัวลดกำลังความถี่วิทยุและ VSWR เพื่อการไอโซเลตอุปกรณ์ขณะ ทดสอบ Bird's directional couplers world renowned for their high-quailty, robust   Board OUT Unit includes: 1. Very important was also the simple construction. 4 GHz) and 12 dB (12. The 3022 is a broadband, dual-directional coupler designed for applications where continuous comparison of incident and reflected power is required. 5 dB to 10. ). Typically specified in dB. Sound Vib. The circuit is based on two AD8307 log amplifiers, which are connected to the forward and reflected ports on a directional coupler. Amplifiers U1:2, U1:3 for SWR-POWER meter,. One additional piece of hardware required to measure the SWR is a directional coupler which can be bought on Ebay for about $10 USD. 1 MHz) I have measured this directional-coupler with my transmitter + power-swr meter + dummy load: 1-30 MHz: power-in to power-out damping is less than 0. More Notes on Directional Couplers for HF -- the Monimatch I purchased my very first SWR meter at the local Radio Shack store back in 1970 when I was a young Novice. The circuit diagram of a Directional SWR Meter is shown below. 45 Top Rated Seller Perfect Theoretical analysis of Alex Directional Coupler. In this case if there is a matched load, then the standing wave along the transmission line will be the same as the incident wave, if the load is miss-matched than the standing wave or the power present at the transmission lines will not be the same to Multi-Hole Directional Coupler. SWR: Standing wave ratio. I Directional Couplers and Bridges Broad band, high directivity, low loss Coaxial directional coupler frequency range from 100kHz to 67GHz WG directional coupler frequency range from 2. Here is a simple SWR protection circuit you can easily build. The ferrite cores I used are Laird 28B0375-400 (Digikey 240-2296-ND). This one has two coupler ports for measuring power and SWR. For custom specification, please contact us. The WM150M measures and displays forward power, reflected power,and SWR simultaneously on it's dual movement meter system in the frequency range. The second coupler can be any model supported by the LP-100A. This family of coaxial directional couplers that are adjustable and externally terminated. Multihole Directional Couplers: SICO offers 6 xx Schematic Directional Coupler and Detector. The Amphenol, APC-7 is a sexless connector with very low SWR. . In either case, the directional coupler will be placed as close to the output of the power amplifier as possible, which means it must perform within spec at high operating powers. RF amplifier protection circuit diagram. A Battery Operated Low Noise Low Frequency FET Amplifier; A Complementary HF Push-Pull Amplifier; A Quad JFET HF Amplifier; A Resistive Feedback HF Amplifier with Lowpass Filter Inserting a directional coupler into the system with a suitable microwave detector to supply feedback to the ALC circuit of a signal generator or sweeper provides a leveled signal at a particular point in the system (Figure 8). (W) Construction Feature Type Pkg. It senses forward (FWD) and reflected (SWR) output power. J. (The cable acted as both the transmission line and the coupler). The SW-200 through-type SWR/ POWER meter which, in conjunction with a directional coupler, can be used in the. Add a couple of diodes and a sensitive meter and you can measure forward and reflected power. For example, when making swept reflection measurements, it is customary to set a full reflection (0 dB return loss) reference by connecting a short at the test port of the coupler. It is a four port waveguide junction consisting of primary main wavelength and a secondary auxiliary waveguide. '/4 db, and SWR of  This video describes how a dual directional coupler that is used in an SWR meter operates. Directional coupler: The transmission line between a radio transmitter and an antenna does not necessarily need to be matched; but the presence of standing waves on an unmatched line creates a problem of power measurement when the intrumentation (as is usually desirable) is located in the radio room. Protection - comparator U1:4,. Struthers-Dunn RF directional watt meter with case. This directional coupler has a high reliability low insertion loss and it is suitable for indoor or outdoor environments. The orientation of any sampling port can easily be changed from forward to reflected by reposition the external termination load on the coupler. The coupling loss dB is a compromise between accuracy and having enough coupled power to drive the detector. By placing a directional coupler between your RF amplifier and antenna/probe you can use an RF power sesnor to monitor the amount of power throughput and verify the measurements from your current monitor/sensing probe and spectrum analyzer are accurate. Save swr coupler to get e-mail alerts and updates on your 2 m KIT for LDMOS amplifier LCD SWR Directional coupler 144 MHz 1000-2000W. A directional coupler can provide 20 dB or more directivity, meaning less than -20 dB of the forward wave interferes with your measurement of the reverse wave. Referenced to the main line output port for use as a leveling coupler. The design of the coupler is critical to the accuracy of the unit. 33 volts) is equal to the voltage that would appear across a 50 ohm resistor (1 volt) added to the reflected voltage (0. xls . Has lighted meter on/off switch. The standing wave ratio (SWR) is the ratio of these maximum and minimum voltage amplitudes of the standing wave. I have modified Paul’s design to use a “Stockton” directional coupler, and to provide a peak-reading capability. SWR Bridge. As a practical application of such a device, an acoustical reflectometer is described. Mainline Loss (dB) Typ. ) Also, notice that the voltage across the 100 ohm resistor (1. $90. SWR is below 1. Narda Directional Couplers and other new and used RF Components products from Test Equipment Center. We worry a lot about Standing Wave Ratio (SWR) in amateur radio since SWR is one indication of how well our antenna system is working. Directional coupler with detectors and DC-output, replacing the poor detector circuit in a citizens band "power/SWR meter". 20. The directional coupler is actually conceptually very simple. 2,504 results for directional coupler Save directional coupler to get e-mail alerts and updates on your eBay Feed. 95 * Buy It SW3a simply goes to a dummy load during calibration. 4 -3GHz. 44dB 1-60 Mhz 3000 Watt Directional Coupler - SO-239 Female Connectors HRO Discount Price: $149. Figure 1 . The standing wave ratio specified for either the main line path This small, light weight digital SWR and power meter uses an Atmel AVR "Butterfly" demo board and a "Stockton" type directional coupler. Antenna or other component to test. 10 dB coupling, 200 watt, "N" connectors, 2 - 4 GHz, SWR = 1. The basis of a VSWR meter is a directional coupler. Anyway, for the life of me I can't figure out how the directional coupler actually works! Directional-Coupler Power Meter Assembly and User Guide Preliminary By: W5USJ CyM-Tech Documentation Services The QRP-DPM Directional-Coupler Power Meter is a kit developed by W1REX and W5USJ with PCB design and artwork by Rex Harper, W1REX; QRPme. Detectors convert For many applications, coupler SWR is important to minimize low mismatch errors and to improve measurement accuracy. The smaller one has excellent directivity up to 1296 MHz, and is still good at 2400 MHz. A Battery Operated Low Noise Low Frequency FET Amplifier; A Complementary HF Push-Pull Amplifier; A Quad JFET HF Amplifier; A Resistive Feedback HF Amplifier with Lowpass Filter Directional coupler and detector diodes from a Toshiba cellular phone. The cross directional coupler Fundamentals General properties of waveguide (directional) couplers Experiment 5 from MTS 7. '/a db, and SWR of  In this case, the VSWR set to 2. Buy or diy? I need a directional coupler for the frequency range of 400kHz up to 150 MHz (20dBm max. By contrast, SWR meters are designed to be used with transmitters and remain in-circuit. 15 Jan 2015 Another important Directional Coupler parameter is Directivity. Directional coupler with detectors and DC-output in a TEKO 371 enclosure. At the show Electronics Research/ERI introduced a series of directional couplers. The 4-port directional coupler Since both toroidal directional coupler (SWC-I, SWC-3) and a strip-line directional couplers (SWC-2) are avail- able, high sensitivity and flat output are assured. We offer coaxial single and dual directional couplers (also know as bi-directional couplers). 5 or the bibliography provided there), we obtain the following scattering matrix for the ideal waveguide coupler. It is designed for AMPS, GSM, WCDMA and LTE band applications. 30 Dec 2015 How to measure VSWR using a Rigol DSA-1000 series Spectrum Coaxial Directional Coupler with impedance match for component being  Coaxial Directional Coupler -hp- Model. The difference between the two ports is the return loss. Trying to build a simple SWR / RF Power meter. 7 out of 5 stars 58 $6. a coupler may be used to determine the lower limit of the reflected power that a particular directional power meter is able to resolve. Cable - RG141 Band 70-146 MHz. 4mm enamel, 30 dB transformer has 31 turns of the same wire diameter (SQRT 100 = 10 and SQRT 1000 = 31. The excellent electrical acteristics of high isolation, high directivity, low ion loss and can reach rigorous requirements of signal sampling, and feed-forward amplifiers. The 20 dB transformer has 10 turns of 0. The AD8307 amplifiers gives a DC voltage of about 25mV/dB of the input signal, which is amplified using an opamp (LM324). This is a very popular waveguide directional coupler. A. New Directional Coupler For Test, Watt meter, Pure Signal etc. ATM coaxial directional couplers are designed, manufactured and tested in accordance with applicable military and F. 82 volts 10 watts = 0. Most SWR meters use directional couplers. 1 dB (attenuator terminated with 50 ohm) Directional couplers 6 dB Coaxial wideband: Sigatek. Directional Coupler as SWR Bridge. Figure 2 — Compled directional coupler. 400. Model Number Case Style F Low (MHz) F High (MHz) Coupling (dB) Nom. The kit is produced and supplied by QRPme. ( dBm, dBW etc. This lets you connect your HF rig and a VHF/UHF dual-band transceiver at the same time. 4 mm female connectors. 5GHz to 325GHz Maximum input power up to 400W Specifications: Coaxial Directional Couplers Model Frequency range (GHz) Coupling (dB) Directivity Power levels on the input & output of the coupler are consistent - very close to 30 dB attenuation (at 14. Both perform the same function, but they have the same physical ports marked differently. A directional coupler is a four-terminal structure, ports 1 and 2 of which are inserted in a waveguide. I don't see the difference, other than perhaps how broadband the coupler is. I am an electronic engineer in the field of RF directional couplers, but I am puzzled about this question, why to use RF directional couplers in some measurements and control processes ? Today I come to this forum to turn to you to discuss my understandings are appropriate. Tiny Directional Couplers Meet Demands of Compact RF Applications. 4-20 GHz), Maximum VSWR (any port) is 1. Calculate (dBm)thepoweratports2,3,and4. Brand New. 4 MHz to 60 MHz (630m to 6m band), with reduced accuracy also in the 4m band usable SWR Bridges. I arranged for the Power meter to cover the range 100mW to 1000W, but it is easy to change the circuit to set upper and lower power limits to any values in the range 100uW to 1000W. I managed to find a wonderful Directional Coupler on Ebay. Measuring 2. Fairview Microwave’s in-stock waveguide couplers are available in waveguide sizes from WR-42 up to 18 GHz all the way to WR-10 up to 110 GHz. 1 So, here’s what I came up with. 5 dB means that the directional coupler can have 9. The circuit below assumes a 100 Watt transmitter and the use of the Dual AD8307 board . by F1FRV. RF_Power_Meter, but it is also useable for Pure Signal . These directional couplers are offered with 10 dB or 20 dB coupling values and have high directivity of 30 dB typical with insertion loss is as low as 0. This line of coaxial directional couplers is adjustable and externally terminated. Later, the coupler is going to be the basis of a SWR-meter, but for now, lets just look at the coupler. Inner conductor with insulation will be used for connection between port1 and port2. Power standing wave ratio Directional Couplers and Bridges Directional Couplers and Bridges SWR For many applications, coupler SWR is important to minimize low mismatch errors and to improve measurement accuracy. Includes (1) 18GHz 1. By using directional couplers and a bridge in combination, it is possible to make an in line instrument that reads directly in complex impedance or in SWR. The annoying mechanical work for the production of tinplate housings had to be dispensed with. It describes and demonstrates how voltages are developed that are . NARDA • L-3 DUAL DIRECTIONAL COUPLER “N” • Model: NARDA 31116, MOTOROLA • 58D09643T03 • 50 OHMS • Frequency: 500MHz to 1. Ancable 2-Pack SO-239 / PL-259 UHF Female to Female Coax Cable Barrel Adapter Connector PL259 Coupler Plug for CB HAM Radio Antenna, SWR Meter 4. For measurements in a 50 Ohm system, 50 Ohm coax and loads should be used. Table 1 lists the DBTC-13-5-75 directional coupler's complete electrical specifications along with specifications for nine additional couplers in both 50 and 75 Ω impedances. The directional coupler transformer is implemented by routing the conductor from the transmitter plug through the middle of a toroid that had the secondary windings on it already. They can Sample a small amount of microwave power for measurement purpose. 4. 3 Answers. SigaTek Microwave Directional Couplers use both lumped element and stripline techniques. The Forward DC voltage also drives a separate Power meter. This dB drop is the return loss (after correcting for the coupler’s loss). Here, Directivity is defined as the coupling from the OUT-to-REF ports minus the coupling from IN-to-REF ports. 18max SWR SMA adapter. Unfollow directional coupler to stop getting updates on your eBay Feed. Make sure to observe correct connection for sensible results. All four ports are (ideally) matched, and the circuit is (ideally) lossless. The stripline directional coupler is a symmetrical device. 8 MHz to 60 MHz. Directional couplers are four-port circuits where one port is isolated from the input port. A directional SWR meter is used to measure the magnitude of the transmitted and reflected waves by sensing each one separately, with the help of directional couplers. Although the coupling factor increases 6 dB/octave below 100 MHz, directivity remains above 36 dB. Another coupling specification is frequency sensitivity. A 1:1 VSWR implies a perfect match between the transmitter and the antenna system. (RF) 3003-10. 4 GHz SWR using a directional coupler. It can handle 300 watts of power and has a PIM rating of -161dBc. 000000. Directional coupler with detectors and DC-output. I don't have a 6GHz vector analyzer or some such, but I noticed that the HAM's were using various "coupler heads" to gauge the SWR of their short-wave antennas: either resistor-based, or more appropriately, actual "directional couplers". Scan the complete range connecting the antenna and measure the return loss. Directional couplers are used to isolate, separate, and combine signals in measurement applications. 6 dB in certain models. Directional Coupler. pdf. • A dummy load may have a 1:1 match but it will not radiate your signal. It was designed by D. "Directional Coupler" (P22. the SWR. Testing antenna's is a lot easier if you have a good swr meter this is a prototype of a design by g7eyt. Specifications of this short-wave power / SWR coupler: Power range: 100 mW to 2 kW Frequency range: 0. The meter automatically provides an accurate readout of SWR for any power level between 10mW and 1000W. com A reflectometer-type SWR meter can be calibrated to give power back and forth (PF, Pr) on a power supply. Legacy directional couplers used parallel transmission line couplers. I have found some, but they are no longer made, or have found others with ultra wtf pricepoints. A little bit of background, I'm in the Air Force and the school I've been to doesn't go into this much depth and the knowledge level at my lab leaves a lot to be desired, so I'm trying to figure out a lot of this on my own. The bord A49 is a directional coupler with more tight coupling, primarily designed for 2m PAs with 100 to 800W RF out. Swc-4 directional coupler, Sw-100a/100b swr/power meter, Rc-10 remote controller – Kenwood TM-521E User Manual Page 23: Swt-1/swt-2 antenna tuning unit, Mb-201 mobile mount, Pg-4g extension cord, Pg-3b dc line noise filter, Pg-2n extra dc power cable Directional-Coupler Watt Meter Assembly and User Guide Preliminary By: W5USJ CyM-Tech Documentation Services The QRP-DWM Directional-Coupler Watt Meter is a kit developed by W1REX and W5USJ with PCB design and artwork by Rex Harper, W1REX; QRPme. 2 db Max • VSWR: Primary = 1. They feature separate HF and VHF/UHF directional couplers, each with its own SO-239 connectors. found on my RF_Power_Meter page to make a SWR Power meter. DC grounded antenna connectors prevent electrostatic build up. Features. In determining length of the directional coupler, in order to have better coupling, we should have a design frequency and arrange the length accordingly. Its main virtue was that it was inexpensive, which was very important to this high-school aged ham! RF directional coupler basics. SWR/POWER METER. 7960, shown at left and in schematic form above, has high directivity, insertion loss of only about. 00000. "So far I am very happy with them. PCB directional coupler for SWR protection of SSPA up to 1 kW level - has some nice photoes of several coupler PCB's. I want to check SWR on a waveguide but i dont have a Network Analyzer i have only 772D dual directional coupler. 15 dB, Directivity 20 dB. 3:1 at 30 MHz. 50-450 MHz up-to 5 kW . The two knobs control the contrast and back lighting of the LCD. The end result was that those antenna taps worked quite acceptably as directional coupler for antenna measurement. There are numerous publications dealing with the construction of directional cou-plers, but some of them are designed for simple applications only, e. 1 dB, which yields very accurate SWR measurements. FR4 double sided pcb was chosen with thickness of about 1/16 of an inch on a 2mil copper thickness. Note that, for an SWR of 1:1, 100 watts equals 100V, peak, but at an SWR of  Coaxial Directional Coupler -hp- Model. (1971) 15 (3), 367-372 THE REALIZATION OF AN ACOUSTICAL DIRECTIONAL COUPLER P. 75 db Max • Loss: 0. Directional couplers are passive reciprocal networks, which you can read more about on our page on basic network theory. PCB Rev 2. Directivity affects SWR accuracy -- poor directivity means that "forward" power is getting into the "reflected" power port and corrupting the reading. There may also be a station-installed directional wattmeter inserted at the output of the transmitter. These used 'forward' and  I am looking for a SWR meter for adjusting 2,4 GHz TX antennas for low (Yes I know I can use a directional coupler but I would like to have a  MARTIN - G8JNJ - Directional Coupler - Martin - G8JNJ - ECLECTIC TV coax, which could be used with a suitable signal source to measure antenna SWR  BIRD400-75-1, BIRD400-25-1, BIRD400-400 Directional Coupler Element, 400- 800 MHz, Bird, BIRD400-50 Directional Coupler Element, 50-100 MHz, Bird,  This directional coupler is based on W1GHZ paper SWR and Directivity are ok for amateur accurate enough power & SWR measurements. DIRECTIONAL COUPLERS High directivity-low SWR 770, 780, 790 Series 770 Dual Directional Couplers The economical HP 774D-777D Couplers cover frequency spreads of more than two-to-one, each centered on one of The directional coupler is used to measure the true power provided by the source to the load. Some of the reflected signal re-reflects due to the output port (test port) SWR. At 1300 MHz, poor SWR & directivity to expect. swr lp, couplers Part # 650750 6-1/8" Coupler w/ (2) Line Clamps But how is the coupler itself working? I've watched How a Directional Coupler in an SWR meter works a few times in the past; the math makes sense but it still's a bit magic to me. A few PCB-based designs can be found in the sheer stretches of the interwebs. This small, light weight digital SWR and power meter uses an Atmel AVR "Butterfly" demo board and a "Stockton" type directional coupler. Hardware is ready. K6UDA Radio – Heil Pro 7 vs RadioSport RS60CF. 5 GHz) corner reflector antenna. However, a circuit based on log amps and a directional coupler that detects the voltage standing-wave ratio (VSWR) of the resulting standing wave can be used to trigger protection of the PA from excessive VSWR values. This means that the through line and the coupled line interact. I use an HP dual directional coupler (778D) all the time. RF Directional Couplers Broadband RF directional couplers are a common component in radiated immunity test systems. Bruene Coupler and Transmission lines. The larger coupler has excellent directivity up to 432 MHz, and is still good at 1296 MHz. The coupling in the 773D changes the same as the coupling variation of the input coupler in the 772D. 8 to 160 MHz coupler for your Low-Band/VHF rig, or select the 430 to 1300 MHz coupler for your UHF rig. • Connectors: IN = “N” Male, OUT = “N” Female It works also well under these frequencies but, with less coupling. com in Limerick, Me. ATM manufactures a wide variety of broadband coaxial directional couplers. 0:1. OK! Broadband 20 dB Dual Directional Coupler This dual directional 20 dB coupler has a frequency range extending over 4 octaves from 100 MHz to 2 GHz. The housing is a very small TEKO box, seen onto the bottom. Keys switching - VT3  The focus of this coupler is on a wide power range and a wide frequency range. I originally up this board to be a piece of test equipment to be used with the. At university we did an experiment by making a directional coupler using a length of ribbon cable. A Battery Operated Low Noise Low Frequency FET Amplifier; A Complementary HF Push-Pull Amplifier; A Quad JFET HF Amplifier; A Resistive Feedback HF Amplifier with Lowpass Filter An SWR bridge is a reflectometer bridge with a meter scale calibrated in SWR. 71 The Tandem Match directional coupler consists of 2x 30:1 transformers. This is based upon the fact that although the reflected directional coupler is oriented such that it will respond only to the reflected Couplers are passive microwave components used for distributing or combining microwave signals. For this purpose it should be connected to the directional coupler of any  30 Dec 2015 How to measure VSWR using a Rigol DSA-1000 series Spectrum Coaxial Directional Coupler with impedance match for component being  10 dB Coupling. Using this approach, an acoustical directional coupler was realized. Steps: 1. The directional sharpness and thus the resolution of the SWR measurement is   4 Jun 2017 Coaxial 50W 10dB Directional Coupler 0. This voltage again can be measured by the ADC in the Arduino. SigaTek directional couplers are in stock and ship the same day. Typically specified as a return loss. 53-230 MHz in nine overlapping bands. The very first idea was to draw such coupler lines on single, double plated PCB. When monitoring the Voltage Standing Wave Ratio (VSWR) using a VSWR - or SWR meter ( NOT a SWAR meter) of the load at the transmitted port (Antenna), both the coupled port and the isolated port outputs are used to sample the incident and reflected power, respectively. I bought three of those directional couplers on eBay and they work very well for measuring PA output power. Sales] Low Power Splitters High Power Splitters Directional Couplers Hybrid Couplers Power Tappers Terminations. The coupling value can be selected 10/20/30/40dB. 0 GHz; Nominal coupling: 20 dB; Minimum directivity: 1 to 3 GHz 3 to 4 GHz 27 dB; Maximum SWR: 1. Scan the complete range without connecting the antenna and measure the return loss. Schematic diagram of the SWR-meter is depicted in fig. For example, a 10 dB coupling ± 0. When a directional coupler is connected to either the Model SW-200 or SW-2000, the power and SWR can be read without any calibration or calculation. More precisely, this is the Voltage SWR ( VSWR , often pronounced as "vizwar"). SWR meters for those frequencies are normally expensive. The Palstar PM2000A wattmeter measures and displays forward power up to 2000 Watts, reflected power, and SWR simultaneously on its dual movement meter system in the frequency range of 1. for SWR Worlds most versatile 1. Looking on the Net it seems a directional coupler could be used to do this. On a waveguide broadwall directional coupler, the coupled port is closest to the output port because it is a forward wave coupler. VSWR and Return  I don't know if it's common, but in contrast to Dave Tweed's answer, at least according to Wikipedia some SWR meters are built using directional  A directional coupler is used to sample the RF energy travelling in a transmission line – useful for measuring power, frequency, and VSWR or impedance. Directivity (dB) Typ. The directional coupler and detector components are from an old VHF SWR meter. Includes elements: 144 - 470 MHz - 1/5/10/50 watts, 200 - 1000 MHz - 10/50/100/500 watts, 2 - 30 mHz - 50/100/500/1000 watts, 50 - 148 MHz - 1/5/10/50 watts, 25 - 52 MHz - 1/5/10/50 watts. It covers companies such as Microlab,KRYTAR,Pulsar Microwave,Vector Telecom,Agilent,Minicircuits,ET Industries,EMC Technology & Florida RF Labs. At Microwave frequencies the directional couplers are a easy tool to sample the microwave energy travelling in one direction. Now the directional coupler's output is connected to a 12 dBi MMDS (2. 71 $ 11 . Power dividers (also power splitters and, when used in reverse, power combiners) and directional couplers are passive devices used mostly in the field of radio technology. A larger frequency sensitivity will allow a larger frequency band of operation. The 50-Ohm dry dummy load works DC to 60 Mhz. Operating from 350. It provides links to useful vendors/manufacturers of RF and wireless products. the directional coupler section. PCB directional coupler for SWR protection of SSPA up to 1 kW level. 3GHz • RF Power: 500Watts • Coupling: -30 db ±0. The display board is mounted to the lid of the tin, so the cover can be closed to protect the display when the unit is not in use or is in transport. 891 volts 1 watt = 0. They are designed to measure incident and reflected power, SWR Values, provide a signal path to a receiver or perform other desirable operations. Inserting a directional coupler into the system with a suitable microwave detector to supply feedback to the ALC circuit of a signal generator or sweeper provides a leveled signal at a particular point in the system (Figure 8). 0 Introduction The MFJ-259C is a compact battery-powered RF-impedance analyzer that covers 0. The directivity could be a little higher but I realize in a broadband application that is difficult to do. M 2. Since you hopefully have a much less power in the reverse wave than the forward wave, you need this isolation to get a good measurement of the reflection. 4. This device is basically the main part of an SWR bridge. Transmission loss: The total loss in the main line of the coupler. One for forward, the other for reflected power. How to measure VSWR using a Rigol DSA-1000 series Spectrum Analyzer. My problem is it is not liner ( I thought it would be ) This is what I get 100 watts = 2. Loss is the actual dissipated and reflected loss. The coupled port on a microstrip, or stripline directional coupler, is closest to the input port because it is a backward wave coupler. Notice the input port and the output port on the upper line and the forward port and the reflected port on the bottom line. High directivity; Minimum coupling variation; Low VSWR. With dual probes to my microwattmeter, I can measure return loss within +/- 0. However, a circuit based on log amps and a directional coupler that detects the voltage standing-wave ratio (VSWR) of the resulting standing wave can be used   The only accurate and convenient way to make return loss measurements is with a well matched high directivity directional coupler or bridge. (and some more) Those directional couplers are sold by many sellers and also on amazon & Co. The output at terminal 3 is proportional with the incident wave penetrating in 2. 0 GHz, 20 dB. 2:1. Impedance matched coaxial cable to connect coupler to the tracking generator. MFJ 864 SWR/Wattmeters MFJ-864. They can be used for measurement purposes or for power leveling. Accuracy of the readings is assured because the WM150 features a true shielded directional coupler. Features: Frequency Range: 1. (refertoFig-1) 1. No NRE required. Used. Internal view of a typical coaxial coupler Figure 3. 1 Max. = 50 150 = 1 3 (18) andSWR = 1+‰ 1¡‰ = 4 2 =2: (19) Inconventional(andcorrect)treatments,theresultingvoltagevariationonthelineisnowinterpreted asthesumofaforwardwave,ofamplitudeVf,andareversewave,ofamplitudeVr. 99 Diamond Antenna SX1100 Dual Power Meters provide a switchable selection of metering from one of two directional couplers in one box! One coupler covers 1. The ports in the directional coupler are: Coupled; Input; Transmitted; Isolated; A special design is put into use by which the input power is split between the coupled and output ports in a specific ratio known as the coupling ratio. S. The coupled port on a microstrip or stripline directional coupler is closest to the input port because it is a backward wave coupler. SWR Bridge is a special case of Directional Coupler. Notes on Directional Couplers for HF Many years ago, when I was a student studying Electrical Engineering, one of my professors mentioned that the Standing-Wave Ratio (SWR) on a transmission line could be calculated by first finding (and measuring) a voltage maximum on a transmission line and then moving 1/4 wavelength away and measuring the Figure 5 – Measured S-parameters for Larger Directional Coupler. These cores seem to handle power levels of up to 500W (200W output has been tested with high levels of SWR). It may also be used for direct SWR measurements if the absorbing attenuator is replaced by a detecting device, for measuring the components in the auxiliary guide that are proportional to the reflected wave in the main waveguide. This is an acceptable SWR. Directional coupler TR1,. Box dimensions  VSWR measurements can be facilitated, eliminating the mechanical motion which illustrates a typi- cal coaxial-line, microwave directional coupler such as. The meter shows the SWR and is used for tuning purposes. Documentation New Directional Coupler. In an ideal directional coupler, the main line loss from port 1 to port 2 (P 1 - P 2) due to power coupled to the coupled output port is: Insertion loss: The actual directional coupler loss will be a combination of coupling loss, dielectric loss, conductor loss, and VSWR loss. In this example the design has been chosen to permit measurement of the SWR of an ADB-S antenna operating at 1090MHz in a 75 Ohm system. zip There are no OSH Park link for this board. Insertion loss . Up for bids is a ef Johnson Viking swr bridge 52 directional coupler. Directional Couplers. It mounts on two standoffs, and the new connectors protrude out the back where the plastic plugs are located on the LP-100A. Thus, the coupler can be used below 100 MHz as well as above. Directional Coupler POWER DIVIDERS AND DIRECTIONAL COUPLERS A directional coupler is a passive device which couples part of the transmission power by a known amoun t ou t through another port, often by using two transmissio n lines set close enough together such that energy passing through one is coupled to the other. Amphenol offers broadband directional couplers for indoor applications. Original Directional Coupler Design . g. There are no reviews yet. O 3KW x 3KW MFJ-259C Instruction Manual HF/VHF SWR Analyzer 2 1. Inside SWR Meters. … Chandler, Indiana USA – April 3, 2018 – Electronics Research, Inc. In The 3022 is a broadband, dual-directional coupler designed for applications where continuous comparison of incident and reflected power is required. Thus, it makes sense to follow High power Dual Directional Coupler. You may then monitor SWR and power of either transceiver at the flick of switch. The DCZ-XXE/Y directional couplers are used for extracting or introducing RF  Coaxial Directional Coupler -hp- Model. Coaxial directional couplers are offered for use at fre-quencies from 100 kHz to 50 GHz, and can be obtained with any of the standard or precision miniature coaxial Figure 1. The operation is also almost identical, the only exceptions being that the two holes are now λ p /4 apart, and a different sort of attenua­tor is used to absorb backward wave components in the auxiliary guide. And in this circuit, it's a bit more complicated, and there's only one transformer instead of two. Rev 2: february 2014 ally manufactured directional couplers are used in high tech equipment, the price of a new one is too high for most radio amateurs, and they are scarcely found on the surplus market. I am leading these currents through diodes into an ACS712 Low Current Sensor, which produces a voltage between 0V and 5V. Available with 4. 3-10, N-Type and 7/16-DIN Connectors, plus options available from 3 dB up to 40 dB. Premium quality RF Signal Distribution Tap / Directional Coupler is used with cell phone repeaters and amplifiers to split the signal disproportionally between many indoor antennas. The main line SWR will remain constant for any orientation of the coupler in the transmission line. The SWR calibration of a directional wattmeter is very simple. Connectorized, SMA,BNC and N connectors. 15. Depending on the application for which it is used, the key specifications of the directional coupler varies. For this purpose it should be connected to directional coupler ( SWR bridge) of any design, say Tandem-match . Stand alone antenna analyzers also are available that measure multiple parameters. The other ports on the directional coupler are normally more suited for lower powers as they are only intended to carry a small proportion of the main line power. RTL Software Defined Radio. This is often done by a sampling technique, in which a known fraction of the power is measured, so that the total maybe calculated. They are not ideal, but they are useful tools. Two use cases are of interest: 1) Specifically for weakly coupled power / SWR probe operation, I'd like somewhere very generally It is a four port waveguide junction consisting of primary main wavelength and a secondary auxiliary waveguide. SWR and Directivity are ok for amateur accurate enough power & SWR measurements. Directivity of 22 dB from 26 dB 70 to 146 MHz. 3 The Directional Coupler. This coupler produces two RF AC currents. 5 kW dummy load has a built-in true peak reading SWR/Wattmeter that you can switch and use independently! Tune up your transceiver, linear amplifier, or antenna tuner into a safe 50 Ohm dummy load at full power. The difference is what you see. So a system that compares direct and reflected signal and triggers when the latter is percentually too high was needed, therefore an operational amplifier was the natural choice. Specifications of this short-wave power / SWR coupler: Directional Coupler: It is often necessary to measure the power being delivered to load or an antenna through a transmission line. Learn more. Directional Coupler made from spliced coax. N8LP's "15 db" pads with 1W resistors for R5, R23 and R26 will do this easily, as those resistors will be dissipating 1/4W each at 1W from the directional coupler. swr directional coupler

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