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I ment ic7 4558d

Do you think ic6 could be the problem? I have a steady 3.6 volts tx and rx? Pin 6

Definitely looks like Q30 Q31 q33 all funny on voltage

More news looks like q31 rx base .673v c 0v e 0v Tx base ov c 8v e 0v

Ok got some free time this morning, I tested voltages on q36 have 5 volts at base and q42 base 4.7v ,collector 4.1v, emitter 4.2v, these two don’t seem right pulled transistors and tested good. Also tested Voltages q43 q44 q16 all tested good, as for the pa jack I tryed but don’t think I have pa.

I will get busy in the morning, I’m sure I can make something work for the pa jack for a test.. I’m going to recheck voltages in the morning on those transistors.. thanks again for your time

I can’t find much info on testing tda2003 5 pin audio chip? I did the ole finger test nothing no buzzing or humming? I do have voltage at one pin on the chip. And do have tx audio

Ok this morning I pulled diodes and found d77 bad... replaced now everything seems to work except rx audio? Meter is working talk back does not work, don’t know if that has something to do with the rx audio.. but transmit audio is good and rf power is good! Dang I’m so close

The radio does transmit and make good power on am no rx audio and meter stuck at 9 s units, ssb works and meter works on ssb but no rx audio

Ok I have 1.5 volt on my collector on q33 I did replace this transistor and it stared transmitting.. I’ve been testing transistors since the post I’ve found q55 q51 q33 all bad... I think something is funny with q33 Base should be 8 V, collector 0 V, emitter 8 volts, I have 1.5 on my collector...

One other thing meter seems to work fine on ssb only but still no sound on ssb

Something else I noticed when the squelch is turned all the way up the meter drops but no sound out of the speaker... I do see the meter move when signal generator is flipped very weak but I see about 2s units

This is a mosfet 520 radio if any one wants to look at the Schematic

Ok got a few of these radios trying to get one working, story to this radio there was an outdoor PA speaker and the speaker was hit by lightning, PA Jack is removed.. originally had nothing at all no Rf power and no receive. I have replaced q51 q55 Q37, powered it up and was stuck in transmit...

Diodes are in right direction

The finals are used from a few 148s had 2312 so don’t mind the poop on the transistors

Let’s try this again cleaned the board and my phone

Ok here you go pic of the finals, and the ground strap to the cap where my pointer is 6.59k Ohm

I think you might be right about the caps being short on each pad???

I got the radio with no finals they were in a bag so this is maybe a possibility I see the extra pad with the no banded side of the diode going to the pad that runs to the biasing vr