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Repair / Help Forum => Repair / Help => Topic started by: pwrmyr on June 03, 2022, 10:18:30 PM

Title: Technics SA-GX303
Post by: pwrmyr on June 03, 2022, 10:18:30 PM
Hello, I have a Technics SA-GX303 that is having a problem. After approx. 30-45 minutes, the unit will shut down completely. If I leave it plugged in, it will come back on after roughly 10-15 mins. and continue to play. It will then shut down again but in less time than before. The unit does get hot on it's top. Looking on the interwebs, I see that the fan only comes on when the volume is turned up, and I can confirm that it does come on around the 11:00 to 12:00 clock position on the volume knob. But that's too loud a volume to play all the time. I've taken it into Galaxy twice, once before the pandemic, problem not fixed and then this year in April, but the problem remains. Vince said it could be the speaker wire or the speakers themselves causing the unit to get too hot. I put on new 16 gauge wire , no fix. Tried running only left speaker with with right disconnected. No fix. Switched to right speaker only, ran nearly 2 hours but still shut down.  Purchased an AC Infinity AXIAL 8038, Quiet Muffin Fan, 120V AC 80mm x 38mm Low Speed to set on top of the receiver and blow air into it, no fix.
Any suggestions or help will be greatly appreciated. I know this is not a very special receiver and maybe I should cut my losses. Thank you in advance.

Title: Re: Technics SA-GX303
Post by: Sir Thrift-a-Lot on June 04, 2022, 10:01:56 AM
I don't know what is wrong, but Vince' answer sounds like the standard line a tech will feed you when he can't find the problem.   What speakers are you driving with it?
Title: Re: Technics SA-GX303
Post by: MacGeek on June 05, 2022, 09:38:16 AM
I don't know what is wrong either, but form your description, it sounds like you might have an impedance matching problem.

I assume the receiver once worked correctly during your ownership.  If so, are the speakers the same ones you have always used?  If not, did the problem start after beginning to use the current speakers?
Title: Re: Technics SA-GX303
Post by: Sir Thrift-a-Lot on June 05, 2022, 01:29:29 PM
I don't know what is wrong either, but form your description, it sounds like you might have an impedance matching problem.

I assume the receiver once worked correctly during your ownership.  If so, are the speakers the same ones you have always used?  If not, did the problem start after beginning to use the current speakers?

That's why I asked what model speakers.   It does sound like an issue with driving too heavy of a load.
Title: Re: Technics SA-GX303
Post by: pwrmyr on June 06, 2022, 12:46:09 PM
Thanks for the response! I?m the original owner since Jan 1992 and the speakers I bought with the receiver are Venturi V820?s. Set-up worked fine for years. Listened to it daily for many years until last decade. They are 8 ohm speakers with recommended amp power between 20-150 watts.
Title: Re: Technics SA-GX303
Post by: pwrmyr on June 06, 2022, 12:50:13 PM
Edit ? ? = ? ? as in I am the original owner and the speakers are V820?s lol
Title: Re: Technics SA-GX303
Post by: Sir Thrift-a-Lot on June 06, 2022, 03:19:55 PM
Thanks for the response! I?m the original owner since Jan 1992 and the speakers I bought with the receiver are Venturi V820?s. Set-up worked fine for years. Listened to it daily for many years until last decade. They are 8 ohm speakers with recommended amp power between 20-150 watts.

Yes, they aren't a hard load at all.
Title: Re: Technics SA-GX303
Post by: scorpio333 on June 07, 2022, 03:03:28 PM
Check this video out if haven't already: http://www.youtube.com/watch?v=qYMR1tPlhJU (http://www.youtube.com/watch?v=qYMR1tPlhJU) The guy is a bit long winded...

I would try positioning the fan to suck air up instead of in. Another option is to run it without the cover, slip it on after use.

I have a receiver Vince worked on twice that after it heats up the left channel goes wonky. I could be wrong, but I suspect he doesn't leave things on long enough for testing. I'm NOT saying he's a bad tech, but he is busy busy busy and some times that means corners get cut to avoid being buried.
Title: Re: Technics SA-GX303
Post by: pwrmyr on June 12, 2022, 12:07:21 PM
For me the link does not seem to be there.
I have seen a couple of videos, on ytube about my receiver.
I will try both the things you suggested.
Thanks!