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Technics pre-amp switching channels

My Technics pre amp SUA900S, keeps switching between channels when I'm nowhere near it. Think it could be a dodgy rotary switch, in which case, where can I find one?

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  • frankoti111 Feb 22, 2009

    My technics control Amp SU C800U (I suppose is the pre-Amp) keep moving from one channel to another on its own - when on CD, it could easily move to Tuner or AUX and could come back to position. It is annoying and keeps cutting off music or radio whatever the case.

    The Power Amp it goes with is Technics SE-A900S.

    This problem emerged approx a year now after 6 years from new.

  • wayneroberds Mar 03, 2009

    Hi petraman7,
    Yes, it's the output sources which it keeps switching between.
    I'll try to get hold of the spray you've recommended.
    Thanks for the tip!

  • Scott Frye
    Scott Frye May 11, 2010

    HI...
    How are you? Better than the amp I see.
    When you say channels do you mean sources or outputs to the power amp?
    If it's a selector switch it might just need a good spraying of De-Oxit contact cleaner.

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5 Suggested Answers

stratcat50
  • 3 Answers

SOURCE: Crown D-150 Amp

Sounds like something was spilled into the amp and it got into the controls, switch and switch knob. As for the knob, lean the amp forward about 45 degrees and dribble hot water into the space behind the knob slowly. Try to keep the water from going inside the amp. Eventually, the knob should come off with some pulling & twisting. Once you get it off, replace both pots and the switch. If water gets into the amp just dry it up with paper towels, etc. and let it continue to dry while getting the new parts. HTH, Emory

Posted on Oct 05, 2007

  • 54 Answers

SOURCE: channel has switched off.

Make shure speaker wires are not crossed at amp or at speaker terminals. Check balance control is at center. Check sound with headphones to see if final amp to speakers is the problem. Try switching imputs on back panel from right to left see if same speaker is on,.Try all loudness controls and tape dubbing buttons to see if any are dirty.
Good Luck
BIG RED

Posted on Nov 03, 2007

SOURCE: Samson Servo 170 - 1 dodgy channel

http://www.soundonsound.com/forum/showflat.php?Cat=&Number=403253&Main=351397

Posted on Dec 17, 2007

  • 6 Answers

SOURCE: Onkyo P-3160 pre-amp doesn't output on the right

Most likely it can be fixed. One of the things that could stymie this is if there is a part that is not available. It also would be nice if a service manual or diagram is available though that might not be essential (a genuine maybe here) if the repairer is familiar with preamps in general. Of course who would repair it and what it would cost are prime considerations. I likely would be able to repair it were I still in business but I am retired and that is not the case. Nor do I believe that even were I not, that this would be possible due to Fix-Ya rules (can't solicit business).

Posted on Jul 03, 2009

caroldon
  • 17129 Answers

SOURCE: Re: Technics HD51 home stereo system (amp, tuner,

The Amplifier must have a high impedance input for the turntable to be connected. Now most of the present day amplifiers do not have this input but only the regular aux input which is designed for a larger signal . But the turntable outputs is quite low and so it requires an amplification of high order. What you can do if you need to play the turntable is to have first a preamplifier with a high impedance which is available even inkit form and can be fitted on to your system. The preamp output can be shared into the input of the source selector maybe with a switch and you willl be able to fix two RCA sockets to accept the input of the phono. This will work fine provided the shielding is done well to avoid the high feedbacck to oascillate and cause noise, the premap must be housed in a shielded cabin. On the other hand you may have to buy a universal amplifier so that the phono input is present. Definetely nothing better than a designed input. So think and decide. hope I could help; Good day

Posted on Aug 10, 2010

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http://www.hifi-pictures.net/amplifiers-home/Technics%20SU-V500/amp.htm

What else is missing from this problem description?

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No cable for technics


I had the same problem with my sua900s pre-amp.
If it's the same cable, you need a (I think 6 pin) mini din cable, male to male. It's sometimes called a PS2 cable (nothing to do with Play Station!). It's the same cable that runs from your mouse into your pc and is readily available for about £5 from online computer retailers. Check the number of pins first though!!

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