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Vintage Amateur and Military Radio Amateur/military receivers and transmitters, morse, and any other related vintage comms equipment. |
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21st Mar 2007, 6:00 pm | #1 |
Dekatron
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Yaesu FT 290 - Multiple faults
Ok, before I go mad looking for faults, has anyone had any of these symptoms, and fixed them?
No RF output power (not the PA Transistor - have changed that) Signal meter endstopped on RX with no signal present Poor RF sensitivity (NIL) Demod problems on SSB/CW There are probably more, but these are the ones that are bugging me at present. Cheers Sean
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21st Mar 2007, 7:12 pm | #2 |
Octode
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Re: Yaesu FT 290 - Multiple faults
Probably best to start looking at the pll/synthesiser if you have these sorts of symptoms - and somewhat confusing, how can you know you have ssb/cw problems if the receive is totally deaf
My FT290 is now over 25 years old and still going strong... I assume you have the manual. Dave |
21st Mar 2007, 7:40 pm | #3 |
Dekatron
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Re: Yaesu FT 290 - Multiple faults
SSB/CW probs are very strange - I think all I can hear is PLL noise - pressing buttons on the front panel just modulates the noise from the speaker.
I only have a copy of the owners manual - no service manual sadly
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21st Mar 2007, 8:14 pm | #4 |
Rest in Peace
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Re: Yaesu FT 290 - Multiple faults
Sean,
Have a look on www.mods.dk in the manuals section. They have a lot of stuff there for the 290. Try the following link and then scroll down to the FT290 stuff. http://www.mods.dk/index.php?ListManuals=yaesu Hope that helps. Regards, Ian |
21st Mar 2007, 10:02 pm | #5 |
Retired Dormant Member
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Location: Bishop's Waltham, Hants, UK.
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Re: Yaesu FT 290 - Multiple faults
Sean,
the RF output, as originally set up, requires the telescopic aerial to be present, and retracted. If the telescopic aerial is missing, the PA will require re-tuning. Jim. |
21st Mar 2007, 10:28 pm | #6 |
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Re: Yaesu FT 290 - Multiple faults
Ok, looks like the VCO isnt too well - I will have a play when I get more time.....
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2nd Mar 2008, 7:55 pm | #7 |
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Re: Yaesu FT 290 - Multiple faults
I know I'm digging up an old thread but I was wondering if you ever managed to rectify the faults with the 290,as I'm experiencing exactly the same problems as you describe.
I did speak to a friend regarding the probs and he suggested replacing D24&D25 (antenna switching diodes) as he says it sounds like the rf is not getting beyond these so any ideas about their exact location on the board would be most appreciated. Cheers for now Mike B... |
3rd Mar 2008, 8:18 am | #8 |
Dekatron
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Re: Yaesu FT 290 - Multiple faults
No, I didnt - I got shot of the radio in the end - a lack of time and interest took over!
Cheers Sean
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