Stryker 955 V2 IF tap for SDR dongle

[Lomchivok]

Was wondering if anyone has done this on a 955 or knows where the proper IF tap area is for the 955 V2.
I'd like to connect my 955 to my airspy HF+ and SDR Console like I do with my IC-7300 with the Inrad RX-7300.
I've used the MFJ SDR adapter junk with no satisfaction other than when I blew it apart with my 8 lb sledge and burned it up in my shop stove.
The mod should be pretty straight forward, just need to know where to tap the IF.

 

[nomadradio]

The challenge is to connect a shielded cable without making it act like a capacitor to ground. Not many places in the radio's IF section where you can solder in a capacitor without upsetting the applecart. A series resistor between the tapoff point and the center conductor will minimize this.

The shorter the cable, the less added capacitance the radio has to cope with.

The schematic I'm looking at may or may not match your radio, but I would use TP23. This is the output of the last 10.695 MHz transformer T6 before it splits off to the sideband IF one way, or to the AM 2nd mixer the other way.

This is the output of an impedance step down, so should minimize trouble from the cable's capacitance. The SDR should be sensitive enough that the isolation resistor won't cause it a problem. I'd start with 100 ohms and compare the Stryker's weak-signal sensitivity with and without the tapoff cable connected. Might need to use a higher resistance if connecting the cable reduces the Stryker's weak-signal sensitivity.

73

 

[Lomchivok]

The challenge is to connect a shielded cable without making it act like a capacitor to ground. Not many places in the radio's IF section where you can solder in a capacitor without upsetting the applecart. A series resistor between the tapoff point and the center conductor will minimize this.

The shorter the cable, the less added capacitance the radio has to cope with.

The schematic I'm looking at may or may not match your radio, but I would use TP23. This is the output of the last 10.695 MHz transformer T6 before it splits off to the sideband IF one way, or to the AM 2nd mixer the other way.

This is the output of an impedance step down, so should minimize trouble from the cable's capacitance. The SDR should be sensitive enough that the isolation resistor won't cause it a problem. I'd start with 100 ohms and compare the Stryker's weak-signal sensitivity with and without the tapoff cable connected. Might need to use a higher resistance if connecting the cable reduces the Stryker's weak-signal sensitivity.

73

Thanks for the info. I'll check out the schematic. I'll do a sinad test before and after to check sensitivity.

 

[sp5it]

Probably you need that kind of interface: https://kd2c.com/hi-z-tap-boards

or diy https://dh1da.darc.de/projekte/Amateurfunk/Panadapter/Panadapter.htm