Sony ICF-SW7600 portable radio -- all static

I've had a great Sony SW7600 portable shortwave/AM/FM radio for years and it has worked very well. It's probably been on for more than ten thousand hours overall. This is the model:

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A few months ago it started giving only loud static when turned on, even when tuned to a standard station. If I left it on for an hour or two it would usually snap back to normal operation and the station would come in clear again. But now it's gotten to the point that it never comes back: only loud static when turned on, and for all the time it is left on. You can faintly detect the signal in the background in most cases, but it's drowned out by the static. (These are strong stations I've listened to for a long time; something changed in the radio, not the environment.)

My mechanical intuition tells me the problem is simple, but I know nothing about electronics. Is anyone familiar with these old workhorse portables? If the repair is more complex than whacking it with a hammer I probably couldn't do it myself, but perhaps it would be worth sending it out for repair? Or should I toss it in the wastebasket? Sell it for parts on eBay?

Many thanks.

Bob

Reply to
RJO
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From your description, it could be a failure of the solder. Sony has been notorious for solder problems depending on the factory and product as well as era it was made. If you can open the set and operate it, then you could gently probe the components with a thin insulated probe to see if a bit of pressure in an area restores operation. One problem doing this is that if the defective joint is actually moved, it can restore operation for hours, days or months before it re-appears, If prodding does restore operation, then it is often effective to simply resolder every joint that looks even slightly suspect with a suitable small iron and top quality rosin solder. If the radio is not RoHS compliant, then use tin-lead 63-37 solder. If prodding around has no effect, the problem might be a defective semi-conductor. You might also consider replacing all the electrolytic caps since they are prone to going high ESR with age, again depending on the date and make.

Neil S.

Reply to
nesesu

What voltage source keeps the stations in memory ?

-- Diverse Devices, Southampton, England electronic hints and repair briefs , schematics/manuals list on

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Reply to
N_Cook

Thanks very much for these detailed insights. Perhaps if I get adventurous (I'm not an electronics person) I'll open the case and poke around with a toothpick to see if it changes anything. It may well be from my amateur position that this will turn out to be more expensive to repair than would be worth it. It has been a great radio though, and if anyone gets the chance to acquire one in good condition they should take it. If the toothpick treatment doesn't work maybe someone will want it for parts, since 90% of it is still in good shape.

Bob

Reply to
RJO

Reply to
staufr1

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