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I forgot to mention, that while I had the VR Pin 1 lifted, I fed 8v to pin 1's trace from pin 6, and it caused pin 6 to bog just like pin 1 does.

pulled C18 and C109 - at the emitter of TR25 pulled C95 - Supply pin of IC3 Pulled C84 - PIN 9 of PLL Did not pull C90 yet, it's really small. removed the bead at PIN 9 of PLL to isolate PLL. I powered on the radio with all of those caps removed and none of this made a difference, Pin 1 of...

Could someone please explain this. What are the solid black squares with white numbers in the schematic? Do they just represent a common rail that is all connected? For instance, the #4 close to the voltage regulator connected to PIN 1... There is also a 4 on PIN 9 of the PLL and PIN 6 of...

My apologies. I found a service manual and excellent schematic here: https://www.worldwidedx.com/threads/sams-photofacts-collection.262787/post-836573

Is there a service manual available online that you know of?

I am using an adjustable voltage bench power supply that I purchased for dabbling in other electronics troublshooting. I have it set at 13.8v and 10 amps. It is currently drawing 0.355 amps with the grant powered up. It operates my Uniden P300 just fine. With the grant powered up, I read...

I just noticed that when TR24 was removed, that the solder was also removed from one leg of D59 and C208. The legs were still in the holes, but were loose. I re-soldered those. Unfortunately this didn't affect the function of the radio, and TP9 voltage is still 6.76.

At TP9, I have 6.76v on ch 1 AND ch 40. Also, when I first turned the radio on, the channel display faded out like it had been doing in the past, but came back at some point while I was probing the VR...probably when I probed each side of the diode...like it needs the 13v from pin 2 to jump...

I took the diode out between pins 1 and 2 of the PLL, this made no difference in the radio function...I believe it tested good when disconnected. I soldered it back in. Where is the audio chip?

Cleaned glue off. Is this a diode? How did it start working when shorted? Did I ruin it by shorting? Is it now backfeeding the VR? When I test it I get same reading no matter which way I hook up to my multi meter. Does it need to be removed for testing?

Pin 1 has been holding at 8v since I shorted the ends of that part. Even when I turn the radio off and back on, and even though it's no longer shorted. I still have no TX or RX, but I did notice that I can faintly hear the PA Audio if I hold the PA speaker on my ear. Also, the PLL voltages...

What is this component that is attached to pin 1? While picking at the glue I accidentally shorted the 2 sides of it together, and my 8v came back to pin 1 of the VR and the channel display came alive. Still no tx or rx, but channel display is on...for now.

Here are the voltages from the regulator: 1: .280 2: 13.6 3: 8.18 4: 0 5: 13.6 6: 8.17 7: Not connected 8: 0.038 I read somewhere else that Pin 8 of the PLL should always be 8v...mine reads basically nothing.

Thank you CSA1863. So it looks like there is a resistor and a jumper in my radio around the near the PLL that are not stock...other than the cut wires. Shouldn't one of the PLL pins have around 8 volts on it? The 2 3-pronged devices that are heat-sinked to the back of the case, are those...

The wires to the add on switches that I cut are near the channel selector on bottom of board.

I can jump the switch wires back together back together, I just cut them to be able to take the cover off...there was no slack at all. Even with the switch wires intact, the channel display still faded to nothing and had no transmit or receive. I'll get some pictures soon.

Thanks for the reply Jeff. I found a cap kit for my radio at Klondike mikes, but it would cost me $51 after shipping and taxes, that seems high.. what's the most economical way to buy quality caps? Any certain brands to look for?