I've attached a picture of my resistive bridge mounted in an altoids tin. And finally, here is the schematic for the swr/pwr meter circuit. The circuit is a variant of the Stockton type of bridge used in many commercial swr/pwr meters and kits these days. UPDATED SOFTWARE NOW AVAILABLE: 1. T1 & T2 in most Stockton type bridges call for an FT50-61 core, but I used the smaller FT37-61 cores to save space, and have had no problems with them when using QRP power levels.
: If you use the same email as someone else at the club, then enter your Name as spelt in the results instead of Email. The two are the same, but the Forward and Reverse outputs are opposite. “An SWR bridge circuit appeared in the winter 1989/1990 edition of SPRAT, the ham journal of the GQRP club.

: If this is the first time that you have used the "Members Only", click [Set/Reset Password]. I used a 20 dB directional coupler design, sometimes called a “Stockton bridge”, that is simple, broadband, and requires no adjustment. Even though comercial rigs have builtin digital readout SWR meters, having an external one is a good idea. Stockton Bridge.

It looks sleek and professional. If you have already registered as a member to use "Members Only" pages of Stockton Bridge Club at Yarm then enter your Email or Name and Password and click [Login]. The only parts you might have to hunt around for are the two 0-50 µA meters. Either my circuit is wrong, or my math is wrong. Here's a simple weekend project that you can build inexpensively with readily available parts from Radio Shack. (Be careful of the direction when winding the coil on the core.) This design is applicable for small or high powers, from 100 kHz (or less) to 50 Mhz, from miliwatts to kilowatts, depending on the selected components. Discussion in 'Homebrew and Kit Projects ... One thing though is I didn't worry about how the bridge balances out, and I assume that needs to be taken into account too. It was designed by D. Stockton, G4ZNQ. I continue building an SWR / Relative Power Bridge. A SWR bridge can be used to check the loss of a long length of coax by putting the SWR bridge between the transmitter and one end of the coax, leaving the far end unterminated, the higher the indicated SWR the lower the loss, e.g. Even though comercial rigs have builtin digital readout SWR meters, having an external one is a good idea. Understanding how to use a SWR meter is relatively easy, but sometimes knowing how to interpret the results and their limitations enables far more to be gained from using a VSWR meter. An Integrated Bidirectional Bridge with Dual RMS Detectors for RF Power and Return-Loss Measurement. Thanks again, Cory KG7BBV

In response to several requests for a VSWR and output power monitor I have developed a simple circuit to be easily added to the BITX (or any transceiver) and some software to get it working.

If you search for 'Stockton Bridge', 'SWR Bridge', or 'SWR Sensor' on the Internet, you can see quite a lot of things you can easily create. The circuit is simple and bridge balance is easily achieved without the usual When I put my DMM on the output I'm seeing a voltage I don't expect. For now, I've just gone with a resistive bridge, though I'd like to build both eventually. The two are the same, but the Forward and Reverse outputs are opposite. 'Stockton Bridge' I made two for testing. If you search for 'Stockton Bridge', 'SWR Bridge', or 'SWR Sensor' on the Internet, you can see quite a lot of things you can easily create. Standing wave ratio meters come in a variety of forms, but essentially they are all used to measure the SWR, standing wave ratio on a transmitter feeder. The circuit is simple and bridge balance is easily achieved without the usual (Be careful of … I experimented with the circuit and found the performance to be excellent. An Integrated Bidirectional Bridge with Dual RMS Detectors for RF Power and Return-Loss Measurement. 0.96" OLED display problem fixed 2. The Stockton Bridge is a widely used circuit. I set my radio to 50w out and key it. An SWR meter can also be known as a reflectometer or SWR bridge. The two are the same, but the Forward and Reverse outputs are opposite. It was designed by D. Stockton, G4ZNQ. I really hope my math is wrong. (Be careful of the direction when winding the coil on the core.) 2 product ratings 2 product ratings - DAIWA CN-460m 140-450 MHZ 15/150 Watt Cross Needle SWR wattmeter
'Stockton Bridge' I made two for testing. An SWR of 2 results in a 50% deflection of the meter, while an SWR of 5 produces an 80% deflection of the meter. I mount the parts and explain the windings on the toroid transformer.