80's Technics Integrated Amps

any one heard an su-v98? are these class d amps - similar to the panasonic sa-xr25/45/57/700 series?

The SU-V series are all what Technics called "New Class A". It's an AB with dynamic bias so that the transistors don't shut off at the zero crossing.
 
Hi kids.
Newbie here and i thought i try my luck on this board.
I have a Technics su v-60 i bought in 1986 or 1987. Used it constantly for more than 10 years , moved to a new place so it got stored away. Took it out awhile ago , new speakers, the old Jamo beasts had to go during the move, unfortunately. I use a Macbook and Iphone as the source. I love the this amp, its my youth with all memories, i refuse to go buy a new amplifier.
Now, it has a terrible cracking noise 80% of the time, one speakerchannel is more or less gone when i turn the balance. I´m struggling to find any clean sound as its cracking and dropping basically all the time, but when i do find a window without the cracking its a wonderful sound.
I do like to think its worse in CD-direct mode, but it could be my imagination. ( i never really understood the CD-direct function as i mostly used a turntable. If anyone can explain it would be nice). Theres also the subsonic filter button , which i think overrides the bass and treble? Or is that the Loudness? Its been awhile since i used this old friend.
Today, for the very first time, i took off the metal cover and the inside was all covered in dust. There was also a weird burn mark in the middle of the (inside) cover, right above the classAA sign of the front.
I googled about cleaning, bought the CRC-electronic cleanerspray.
I don't know anything about electronics and tech stuff, so my question is if you have any idea what to do about these problems. The only thing i´ve done so far before this post is wiped off some of the dust with a cloth and sprayed a little on the balance pot meter and worked it. Its still sitting with the cover off.
I realize it would propably cost too much, even if i can find, someone professional for this so i´ll give it a shot here.
Any help would be very much appreciated.
Would pics be of any help?

Rick
 
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A temporary fix would be to turn off the amp and move every conrol and switch back and forth many times .

But Rob is right .
 
A temporary fix would be to turn off the amp and move every conrol and switch back and forth many times .

But Rob is right .

I´ll do the cleaning process step by step tonight and see what happens. Hopefully i won't have to take off the front.
Is the airspray any good in this case? The amp is so dusty inside after 25+ years.
A friend of mine told me these old amps holds a lot of electricity even unplugged, it could hurt you, is that correct?
Thanks.
 
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Canned air can be used to clean out the interior of the amp. The things in amps that hold a lot of electricity are the large electrolytic capacitors. They are usually black, and are shaped like small beer cans. Don't touch the terminals of these - you could get a shock. There is usually two of them - sometimes four.
 
I took off the front on one of my Technics integrated amps and it was very easy to do. For the volume pot I had to undo it from the front plate in order to get the cleaner into it. Not very hard either.
 
Ok, phew, so i got the front off.
Any advices what else to do other cleaning before i put it together again?
The CD-direct button is marked orange. Anything i could do with it?
 

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Ok, so its back together, but now the red lamp-current drive was on first but its off now. I tried to cut the power several times, but it won't come on again.
Oh well... sorry for my ramblings.
 
The entire amp won't come on, or just the red lamp?

I have no idea. How can i tell? I don't get that clicking sound a few seconds after startup anymore. This has never happened in the 26 years I've had this amp, so its safe to say i sce**d something up cleaning it.
The first startup i did after cleaning it, the red lamp current drive came on as usual. I had speakers, 8 ohm plugged in. I then plugged in a RCA Belkin cable into the aux channel (8 i can't remember which channel it should be), then the red lamp current drive went off. I have a feeling that caused it but I'm not sure.
 
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Well, maybe not. Did you let the cleaner dry for a long time before powering it up? Maybe the on/off switch has gone south. That's a very common issue with Technics amps from around that time. I had to rebuild a switch on my Technics amp, just to get it to turn on.

Did you double check all the wiring harnesses that you unplugged?
 
The entire amp won't come on, or just the red lamp?

I have no idea. How can i tell? I don't get that clicking sound a few seconds after startup anymore. This has never happened in the 26 years I've had this amp, so its safe to say i sce**d something up cleaning it.

Edit: Now its on again. I unplugged the speakers and cut the power for awhile.

Can you explain the voltage control/ current drive feature please?
Is it like a fuse?
 
Well, maybe not. Did you let the cleaner dry for a long time before powering it up? Maybe the on/off switch has gone south. That's a very common issue with Technics amps from around that time. I had to rebuild a switch on my Technics amp, just to get it to turn on.

Did you double check all the wiring harnesses that you unplugged?

It took me 3-4 hours to take it apart and put it back again. During that time i used the spray.
Its back on now.
 
Edit: Now its on again. I unplugged the speakers and cut the power for awhile.

Can you explain the voltage control/ current drive feature please?
Is it like a fuse?

I'm glad it's back on.:thmbsp:

As for the current drive feature - I have no idea. Maybe someone else will come along and explain it.
 
I'm glad it's back on.:thmbsp:

As for the current drive feature - I have no idea. Maybe someone else will come along and explain it.

Ok, thanks. I have to think through what to connect to this amp. I still have my old SL B2 turntable and the SL-PS700 cd-player, but would rather use more modern devices such as Iphone and Computer, but maybe that won't work out.
 
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If it is the power switch there is a place here in Colorado Springs called Centennial Electronics that sells an OEM replacement (exact Matsushita replacement). I have replaced two of them.

Is it putting out sound now?
 
You should be able to hook up your phone and computer. You will need cables with RCA jacks on one end and 1/8th inch male jack on the other end.

Hook the 1/8th inch jack to your phone or computer line / headphone out - easy. :yes:

edit: something like this will work:

http://www.amazon.com/Hosa-Cable-CM...1387764137&sr=8-1&keywords=rca+to+1+8+adapter
Thanks. I have this one: http://www.belkin.com/IWCatProductPage.process?Product_Id=424430

If it is the power switch there is a place here in Colorado Springs called Centennial Electronics that sells an OEM replacement (exact Matsushita replacement). I have replaced two of them.

Is it putting out sound now?

The power switch has never been a problem. Just CD-direct,. balance and dropout of sound.

It is, and with a lot less crackling. All of a sudden i get a a very very loud BANG , i jump up every time that happens. The volume is set to O though. Weird.
 
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