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tr49 was the culprit. Thanks for the info. I appreciate it

I've got a galaxy dx44v on the bench and I've hit a wall. I'm getting receive audio through the radio but cannot get tx audio through it. I've traced it back to C191 on the board and seem to lose it after that. Another thing I have noticed on the voltage of tr51 the middle leg of the transistor...

I've been looking for a replacement for the erf7530 transistor. Seems they are getting hard to find since palomar changed hands.

yep that was it. the bias component was shorted to ground. got it fixed. The rfx85hd is shot. the transistor is gone in it. radio works fine without it. Is there a feasible replacement for a on board amp?

Ok my problem is there I have no voltage on the gate of the final.

Correct me if I'm wrong shouldn't the final have some gate voltage to turn on the mosfet so it would amplify the signal. At this point it has none when keyed

Sorry I was a bit tired last night. It does have a mosfet final but has all the parts install and removed for it. Reason I put a mosfet final in originally was because the customer wanted a rfx85 amp added to the radio and was using it to drive the amp. Radio is the 29LX been working great for...

ok found part of the problem. had a bad driver. just low output now. Radio has a mosfet installed on the final. getting little less than half watt deadkey with a swing up to 2 watts.

d8 diode checks good also getting 13.8 voltage to the collector of the final and driver. I put two new transistors in. still no output. Note: I have a oscope, multimeter and a bench freq counter. Not as familiar with the Cobra radios as i should be because I rarely work on them

Ok I'll give it a try and let you know how we turn out.

I have a Cobra 29 on the bench I'm having a little trouble nailing down the problem on. I'm getting a good signal to the base of the driver but not to the final. The signal on the collector of the driver less than half of the signal on the base. For instance on 19 when keyed the signal on the...

I generally only ask if I've been in it a day or so and haven't found my problem

Found my problem. Bad solder joint on one of the vco cans

Checked that out. Had no luck there. Just figured it was a common problem getting off one channel

Got a cobra 29ltd that is 10khz off frequency. Example on channel 19 the frequency counter shows 27.195.

Yeah I think I'd like to see one operate in person. Seems to be the thing to have though

Ok. after losing my mind and half my hair I finally came back to the audio chip and determined the part i replaced was defective then replaced it and now i have receive audio again. Now I still have no tx audio. According to the oscope I have good audio out of IC4.

I have a understanding that pulling individual components in the suspected circuit and testing them is a common way of finding faults in a circuit. My question is there a better way to find faults with the right tools?

Also noticed the audio chip is getting hot

I did notice while keying and unkeying the radio the recieve would come in for a split second. So I went on to check voltages at tr36 and tr37 since I checked tr38. Voltages werected good at these points