Magnum S9 no ssb receive final bias stuck on fm all ok

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Abikerlad
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Posts: 2
Joined: Monday 11th Mar 2013, 6:43
First Name: Jason
Location: London

Magnum S9 no ssb receive final bias stuck on fm all ok

Post by Abikerlad » Monday 11th Mar 2013, 6:52

Radio Make and Model: magnum s9
PCB Number:
PLL Number:
Test gear available: most of all needed. Frq counter, freq generator, scope, meters, capacitor esr tester.
Symptoms: when selecting ssb the current draw on the psu shows as much as full power draw on fm tx. I hear nothing on ssb. Also on fm I hear some buzzing and strange noises volume also changes a little on its own, but it's more or less working fully on fm receive.

What is working: fm tx and receive okish ssb tx working,

What has been tried: removed driver legs from board when I select ssb the current has stopped being drawn but still nothing on ssb can be heard its very quiet.

Did it suddenly happen ?: I received this radio to repair
Anything else that may be of help?:

zodiac
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Posts: 319
Joined: Sunday 7th Nov 2004, 13:58
Location: UK

Re: Magnum S9 no ssb receive final bias stuck on fm all ok

Post by zodiac » Wednesday 13th Mar 2013, 11:15

Hi Jason and welcome to the forum.
That's a strange one you've got there, try de-soldering the finals to see if the amps drop and tell us what the finals are, Mosfets or 1969's.
If you have a shorted final it will kill the receive.
How far is it.
Twice it's length from halfway.

Abikerlad
Newbie
Newbie
Posts: 2
Joined: Monday 11th Mar 2013, 6:43
First Name: Jason
Location: London

Re: Magnum S9 no ssb receive final bias stuck on fm all ok

Post by Abikerlad » Thursday 14th Mar 2013, 4:52

Hi thanks for the reply have un soldered all outputs including driver, current is not being pulled on received now, but still silent on ssb receive.
So not sure why now.
Cheers Jason

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