98vhp no transmit

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zinger827
Dead Key
Dead Key
Posts: 35
Joined: Saturday 5th Apr 2008, 4:16
Location: Maine

98vhp no transmit

Postby zinger827 » Monday 27th May 2013, 12:41

Radio Make and Model:
PCB Number: EPT690010D
PLL Number:
Test gear available: vom meter, freq. counter
Symptoms: No Tx.

What is working: Everything.

What has been tried: Tried replacing mosfets. irf520's

Did it suddenly happen ?: yes
Anything else that may be of help?:

zinger827
Dead Key
Dead Key
Posts: 35
Joined: Saturday 5th Apr 2008, 4:16
Location: Maine

Re: 98vhp no transmit

Postby zinger827 » Tuesday 28th May 2013, 0:35

Hi I am getting
q47 - 5.70v rx on drain gate 0.00rx - 3.75tx 0.00 on source
q48 - 5.56v tx on drain gate 0.00rx - 3.82tx 0.00 on source
of finals

q49 - 5.70v rx on drain gate 0.00rx - 3.90tx 0.00 on source
driver
I do have another radio on beside it and does show a carrier and when touch the drain on finals shows more of a carrier on other radio but no modulation. Meter on 98 shows no output like the other radio shows a little signal.
The amp is totally disconnected from radio. The amp is fine just the main board has no Tx power.

zinger827
Dead Key
Dead Key
Posts: 35
Joined: Saturday 5th Apr 2008, 4:16
Location: Maine

Re: 98vhp no transmit

Postby zinger827 » Wednesday 29th May 2013, 9:03

Looking at schematic I'm getting 6v to L31 and C200 but from C200 to c201-c202 and c197 not getting the 6v power? Would that keep me from getting Tx out? If I touch them other coils with meter lead it gets a signal reading on my other radio but no RF out?

zinger827
Dead Key
Dead Key
Posts: 35
Joined: Saturday 5th Apr 2008, 4:16
Location: Maine

Re: 98vhp no modulation

Postby zinger827 » Monday 3rd Jun 2013, 2:20

Ok I got Tx back the L44-43-42-40 was out of align. But I still have no modulation? Plus I get a 120+ watt deadkey on SSB? Rx is fine. ic7 is good.


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