Uniden 980 ssb 8 volt transmit

[DXQUEEN]

Hello everyone bought a RFX 95 kit to put on my uniden can anyone tell me where to get the 8 volt transmit spot in this radio. It's my radio just doing a lil experimenting. Thanks to anyone that can help.

 

[711]

Hello everyone bought a RFX 95 kit to put on my uniden can anyone tell me where to get the 8 volt transmit spot in this radio. It's my radio just doing a lil experimenting. Thanks to anyone that can help.

Is there a 7808 device on the side of the chassis?

 

[Transresistor]

It has to be a switched 8 volts positive while in the TX mode. Do not use a constant 8V source like the 8V regulator on the side. That will not work!

 

[nomadradio]

With no schematic to be had, finding a foil trace near the power stages that feeds transmit-only power to the bias pots and the transmit-mixer chip would be the thing to do. A 'scope would reveal if you're probing a power-only foil trace, or some circuit point with a signal on it that you don't want to contaminate.

73

 

[brandon7861]

 

[brandon7861]

See those two big caps in the corner, left one is for the 5v regulator Q415, the right one is for the 8v regulator output. That first device on the heat sync near those caps is the 8v regulator. Q427 is a PNP transistor and is the TX switch that feeds 8v to the rest of the radio during transmit (when its base is pulled low). The lower left lead under the red circled collector lead is the base, emitter on right.