ICOM IC-R7000

[chr999chr]

Hi All

I am trying to bring back to life an old R7000. I have repaired the PSU which brought it back to life. Then there was no SSB rx the needle went hard right. I found a faulty diode on the IF board. All seems to be working apart from low receive on all frequencies. it is about 4 or so S points down everywhere. I have re capped the PSU, DC-DC converter and the IF board. All voltages seem to be reasonable from the DC-DC converter. I don't think its out of alignment as its everywhere and I could probably recover maybe 1/2 S points on an alignment but not 4 or so.

Any ideas on where to go next? Any common faults?

 

[spongella]

Not familiar with that radio but I've restored quite a number of radios (both xmtters and rcvrs) over the years. Alignment would be your best bet if you have the test equipment to perform it. I've worked on old radios that in the end didn't need alignment but there were a few that performed better after adjustment. If you can get ahold of the repair manual with alignment procedures, see what's involved. Calibrating the S meter is sometimes part of the alignment process.

Also, with old radios there's always a possibility that someone in the radio's past has made adjustments without proper knowledge.

You seem very competent in repair so realignment makes sense. Good luck and I hope you get the 7000 up to speed.

 

[RFI-EMI-GUY]

Hi All

I am trying to bring back to life an old R7000. I have repaired the PSU which brought it back to life. Then there was no SSB rx the needle went hard right. I found a faulty diode on the IF board. All seems to be working apart from low receive on all frequencies. it is about 4 or so S points down everywhere. I have re capped the PSU, DC-DC converter and the IF board. All voltages seem to be reasonable from the DC-DC converter. I don't think its out of alignment as its everywhere and I could probably recover maybe 1/2 S points on an alignment but not 4 or so.

Any ideas on where to go next? Any common faults?

The RF front end(s) plural, because there are several band sections, are Varactor tuned and I think slaved from VCO steering voltages. If those are out of whack due to power supply ripple ( a known problem) or voltage gain discrepancy, the sensitivity will suffer. Perhaps the schematic and the pots associated with tuning those sections will give a clue.