R71a silly question???

[drailog]

I turned on my r71 and the S meter is fully to the right and the SIG indicator is on I can not get the s meter back to zero, there is no antenna attached and no audio, has to be something simple. No switch or button seems to help.. it is like it is receiving a 50 over signal

 

[Blackswan73]

Check the RF gain. If it is fully counterclockwise, you will get a result like that.

 

[drailog]

I have tried every knob and every button, s meeter is fully yo the right and there is no audio, worked fine yesterday when put in the box, took it out tonight and the issue showed up, it is somehow locked.

 

[Blackswan73]

Does the VFO work? Can you change frequencies? Can you pull up freqs stored in your memories?

 

[k9rzz]

Ugh.

No hiss from the speaker? Yes, can you change frequencies? mode? What happens when you do hook up an antenna to it?

That's a great radio, but unfortunately an old one and capacitors do go bad. :^[

 

[drailog]

antenna makes no difference, it is like it is receiving a full quieting signal or like the squelch is fully closed like on 2 meters

 

[k9rzz]

No answer to your question, but it's happened to others: Dead R71A - do these symptoms ring a bell with anybody?

You might join this Yahoo group and ask over there. Lots of knowledgable folks there: https://groups.yahoo.com/neo/groups/ICOMR71A/info

 

[DaveNF2G]

I think post #2 is the answer to your problem.

 

[ridgescan]

I think post #2 is the answer to your problem.

That symptom sure points to the gain.
Rail-can you get another pic of the radio, this time full face and in AM mode? It could be something as easy as the gain control needing to be worked back and forth with maybe a small shot of cleaner.

 

[902]

I found this by poking around:
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Knowledge Base Article 5BMC2631A7

Issue
My R71A has no audio. S-meter fully deflected.

Resolution
-10 volt DC-DC converter failure. Replace faulty DP-2 module (IC-6) on the matrix unit.

=====
You will need to either find - or construct - a replacement -10 volt DC-DC converter. Icom might have them, although the R71 is sufficiently old that they might not support it. Digikey has DC-DC converters, but you might have to build around what they have to make it work.

There was one webpage that had Japanese writing with a breadboarded replacement that someone made. I can't find an English version or a page other than the JPEG.

 

[Blackswan73]

That is quite possibly it. You might try tapping it. My be bad/broken solder joint, or unseated cable/connector

 

[902]

That is quite possibly it. You might try tapping it. My be bad/broken solder joint, or unseated cable/connector

Maybe, but I was thinking an electrolytic capacitor (or few) that has/have dried and devalued out of functional tolerance. The R7000 radios are terrible for that. Come to think of it, I've also seen that in Uniden/Bearcat 800 XLT scanners.

 

[Blackswan73]

I was shooting for the easiest options first . Many times I have fixed various equipment by simply reseating connectors. They sometimes become oxidized with time, and pulling the connectors and reaseating them, cleans them up enough to start working again

 

[902]

I was shooting for the easiest options first . Many times I have fixed various equipment by simply reseating connectors. They sometimes become oxidized with time, and pulling the connectors and reaseating them, cleans them up enough to start working again

After they made most of their equipment depot service only and phased out component-level field technicians, Motorola used to called that "the three R's." Reset, reseat, replace.