Maitner STR-50 power up issue

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Good day.
I was recently given a Maitner STR-50 because of this issue, and I figured I'd give it a go and see if I can fix it.

The issue is this. To turn it on, i have to tap the power button over and over again until it "catches" and stays on. I'm figuring this is a relay issue, which hopefully will be an easy fix. The real issue is that once it turns on, it will produce sound for about 5 seconds, then fade out to absolute silence. A while ago, the fuse started blowing, and two of the caps needed to be replaced. I have a feeling this issue might revolve around the other caps that are still original, but thought I would get some second insight in case my thinking is off base. I've got a lot of experience with tube audio, but solid state is something I've never delved into. I can't imagine it's very different, but as I said, better get some input first.

Thanks for your help.
 
Why don't you contact John Wright of Museatex which was part of Meitner. John does all the Meitner and Museatex service as well as all their upgrade design work. You can contact John at :: meitner::. The STR 50 and the STR 55 and the MTR series of mono blocks as well as the Melior range are excellent amplifiers and well worth service and upgrading. For what it is worth the STR 50 was designed and voiced using Acoustat 2+2 loudspeakers so these amps are a superb choice for electrostatic speaker fans. No one knows these amplifiers as well as John does. Hope this helps. Best regards Moray James.


Reliability Updates from Museatex/Meitner site.

The power switch, which was previously a triac in the primary side of the power transformer,
has been replaced by a Scritch. The Scritch, an SCR - based circuit, is positioned in the power
supply after the diode bridge. This provides for soft turn on and better long-term reliability.
There are some small, but significant changes to the compensation and servo circuitry,
making the amp completely immune to load variations.
The pre-drive transistors have been upgraded to a new Motorola device. This part is
faster and shows less variation from the manufacturer.
 
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