Sony STR-7045 - One channel cuts out intermittently

tsuji

New Member
I picked this receiver up on eBay a few years ago for my bedroom after I recognized it as the one my father had when I was a kid that he swore by. It performed flawlessly for years and still sounds great, but the right channel began cutting out intermittently.

- Doesn't matter which input.
- Kicks back in when unplug and replug 3.5mm cable from computer or iPad, usually with a loud pop/crack
- I haven't done any cleaning / maintenance / inspection, and I don't think the previous owner had either, at least in a good while (some crackling when turning volume, speaker select, input switch)
-I've never done any work on any audio components and don't know much about their guts, but am not afraid to get my hands dirty and am fairly technologically savvy (have done somewhat similar things like build PCs)

Does the nature of the issue point to a likely culprit? Is it something a novice would likely be able to spot/identify on inspection? Am I just as likely to do more harm than good by opening it up? I found threads on similar problems where replies pointed towards speaker relay or cold / cracked solder? But most of those issues seemed a little different, often limited to a single input or affected by volume.

Any input would be greatly appreciated!
 
Hi,

Try De Ox on the switches and pots. Often these components, over the years of use and non-use, get crud built up on the contacts. I found the Tape Monitor switch in Sansui's to be a major source of intermittent sound.

I have just finished re-cappinmg and cleaning up a Sony STR-7025. They are easy to open and the various switches and pots are accessible. If I was you I would give the De Ox a go for starters, and then see how it goes before deciding the next course of action.
 
Next step (after cleaning the pots and switches ) could be a visual inspection of the solder side of the boards. Bad or broken solder can cause intermitent cuts.
 
Use LPS-1, contact cleaner or faderlube on the controls- safer than using Deoxit which attacks the substrate the carbon track is applied to.

Clean switches with any of them. The other advantage of LPS-1 is you do not need to wait for it to dry completely. Of course where you are in the world also dictates what is likely available to you as well.

And then if it still persists, follow up with Elnaldo's suggestion, but if nothing stands out, reflow all solder connections on the boards making sure the solder wets the leads of all components.
 
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