Author Topic: Akai amplifier repair source selecion switches help  (Read 312 times)

Offline AudioRecycle

Akai amplifier repair source selecion switches help
« on: May 30, 2018, 01:16:30 PM »
Hello

I am trying to fix a Akai AM-U110 stereo integrated amplifier. https://www.hifiengine.com/manual_library/akai/am-u110.shtml

I have tracked down the problem to a bad switch i.e. the SOURCE - TAPE selection switch SW1-1. See the red arrows in the schematic.jpg file. I can hear the audio volume change and sound popping and crackling when I wiggle the push lever on the switch. It happens in both positions of the switch on both channels.

Schematic
https://postimg.cc/image/5mljt4ntj/

Photo of switch. (In both photos its the switch on the left)
https://postimg.cc/image/6c4c5kw3r/
https://postimg.cc/image/xzh1jqu5z/

The symbol on the switch looks like the matsushita emblem in this list. The first one with the triangle and arrows. https://www.electronicspoint.com/resources/logos-for-electronic-component-manufacturers.47/

My problem is.. I dont know what this type of switch is called, don't know where to source it. The white body length is about 18mm and from memory the width is 10mm or 7mm. Cant remember.

Also it must be a switch with 4 x double throw switched as indicated in the schematic. Such a switch have 12 legs. But this only have 10 legs. 3 on each side for the double throw to select between tape and source and the other two legs on each side is then single throw switches for the leds.

Any help?
Thanks?   



Offline marantz123

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Re: Akai amplifier repair source selecion switches help
« Reply #1 on: May 30, 2018, 09:04:20 PM »
Have you tried cleaning the switch out with an appropriate switch cleaner? Secondly, there is an article about stripping and cleaning these switches in vintage Marantz gear...but I cannot reccomend this as never needed to try it and it may be tears if cannot put humpty dumpty back together again. Clean it out with a spray type cleaner....very good chance thats all it needs. Good luck!  :thumbs:

Offline fdlsys

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Re: Akai amplifier repair source selecion switches help
« Reply #2 on: May 30, 2018, 11:41:50 PM »
Agree with clean and lube.
But if you do need a new one, RS Electronics in Selby had them.
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Offline AudioRecycle

Re: Akai amplifier repair source selecion switches help
« Reply #3 on: May 31, 2018, 04:26:32 PM »
Have you tried cleaning the switch out with an appropriate switch cleaner? Secondly, there is an article about stripping and cleaning these switches in vintage Marantz gear...but I cannot reccomend this as never needed to try it and it may be tears if cannot put humpty dumpty back together again. Clean it out with a spray type cleaner....very good chance thats all it needs. Good luck!  :thumbs:

Hi Marantz123

I had a good laugh at your humpty dumpty comment now because that was my exactly my thought last night as I stripped the thing. Was damn near impossible. Lot of head scratching and awkward holding positions . Another thought came to mind at round about 12. It was "Akai... Akai..." and then "Its more like Kakai. At least I laughed at myself.

I took the easy way out since this switch mechanism felt a much more loose than the other similar switches. I think that switch was worn out completely. The person that I am fixing it for said its ok I may bypass the switch. So I did. Can still do all they want but just not use the tape player input. They dont have a tape deck. And if they want to use one in future the can input it through AUX.

So thanks. I will keep a lookout for that Marantz document

Offline marantz123

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Re: Akai amplifier repair source selecion switches help
« Reply #4 on: May 31, 2018, 08:05:23 PM »
U stripped the switch...?.. :faint:..at midnight..while chanting some magic words.......brave fellow you are! Any pics?  Great that you got the input working,  its hard to believe that the switch is completely worn out....unless there was a parrot...with a repetitive compulsive disorder who switched that poor switch 100times a day for 20 years with his little beak until he went to fly with the angels.

The Aux input may not be sensitive enough for a tape/magnetic head signal. Tape-heads here could advise.