Radio Make and Model: Electrophone GME TX840B
PCB Number:
PLL Number: toshiba TC9106BP
Test gear available: Multimeter, Power Meter, Dummy Load
Symptoms: only 2 watts output power on SSB full 5 Watts on AM
What is working:Everything works on the radio it just has low power output on SSB TX
What has been tried: Marked all the Trimmers ( VR's) with marking pen first then tried turning each VR clockwise one at a time while TX on SSB and speaking inti Mic as in a long AHH or Ola, no increase in SSB TX Powr, however full 12 Wall on whistle, obviously the radio has been tuned in the factory with a high pitch audio oscillator, a bit silly when the Human voice is a lot lower in frequency.
Did it suddenly happen ?: The Radio is Brand New out of the box, yes , has been in storage since purchased and first given to Son-In-Law about 10 to 15 years ago, has never been used until a week ago, it is still in as new condition ( Mint Condition.
Anything else that may be of help?: What I need is to know exactly which VR's do what and also Coils etc. Alignment Proceedure, I have looked for this info for hours on the net to no avail, GME website only have the User Manual to download no Service Manual available , the only other solution that I can think of is using a Power Mic to drive it harder as a high pitch whistle into the Mic makes the old dear boogie, Human voice is too low in frequency to drive it like a whistle does, anyway hopefully someone here can suggest a fix, many thanks for reading my post, cheers for now and Happy New Year to all de Wazza
Electrophone GME TX840B SSB Low Power
- The Defpom
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Re: Electrophone GME TX840B SSB Low Power
I dont have any info on that model myself, but it sounds more like a bad capacitor (or a few of them) in the audio path, effectively hi-passing the audio, cutting off the lower tones.
An incorrect SSB offset calibrations could also be possible, resulting in the frequencies being cut by the IF filter.
An incorrect SSB offset calibrations could also be possible, resulting in the frequencies being cut by the IF filter.