President Grant no rx and no tx!

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Dead Key
Dead Key
Posts: 11
Joined: Thursday 28th Aug 2008, 9:42
Location: SWEDEN

President Grant no rx and no tx!

Post by wiking »

Radio Make and Model:President Grant DX
PCB Number:PC-999AC
PLL Number:
Test gear available: Freq,Counter multimeter tone gen,
Symptoms:The radio does not rx or tx

What is working:It lights up.

What has been tried:I have checked all the diods = ok, TR 23,31,32,33,37,36,35,38,39,24,40 checked ok

Did it suddenly happen ?: No i got the radio this way.
Anything else that may be of help?:First thing I notice was that it draw a lot of amps and smoke came from R124,and one pin on the sound IC gots warm,
I change all the 10V caps one was shorted and the R124 resistor and now the current seems to be normal and nothing heats up.
I have no buzz in the speaker and the rx led and the tx is glowing at the same time and if I hit the tx button in PA mode they gets dark in normal mode they are still glows tx,rx.
I can see on the S-meter that its not receive any thing and I have checked the output and it does not transmit either.

Per A
Posts: 7
Joined: Friday 25th Sep 2009, 16:08
First Name: kc
Location: Fort Collins, Co

Re: President Grant no rx and no tx!

Post by Sci_Fi »

If this sounds stupid just disregard...but I know this.... some mostly older radios are relay switched, this could be one of these radios. They take a different mic wiring to work correctly that could be why your TX/RX are on at the same time wrong mic wiring. What kind of Mike are you trying to use with this radio? Is it stock? Check the pin wiring guides for this radio... good luck. if it not this oh well its worth a try. :doh:
Technical Helper
Technical Helper
Posts: 319
Joined: Sunday 7th Nov 2004, 13:58
Location: UK

Re: President Grant no rx and no tx!

Post by zodiac »

Re check TR35 and 37 they are both PNP 2SB525 1 AMP transistors, also check the zener diode D59 5.1v.
How far is it.
Twice it's length from halfway.
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