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Starting up a lost MM

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Jeremy Shaw (jemshaw)
Username: jemshaw

Registered: 09-2006
Posted on Wednesday, April 13, 2011 - 07:21 pm:   

Just wondering if there is a good technique to start up a MM that maybe hasnt been used for 8-12 years. In an all valve amp I would pull the tubes and check the heaters first then switch on the standby and check high voltage caps formed up ok probably on a variac and gentlly gently. Then retube and chocks away. However Im not sure with all that modern (sic) SS stuff in there what a good way would be , I have started old musicmen before with dubious storage /misuse and no use before and they have all just roared into life (even one that later proved to have exploded caps ,(it was quiet though)).I may have been lucky but many other stories on this forum just start em up and all has been well. Any thoughts on gently start up or just trust to luck and damn the torpedoes
Mike Kaus (mm210)
Username: mm210

Registered: 05-2006
Posted on Thursday, April 14, 2011 - 03:26 pm:   

If I have a suspect amp, I usually use a current limiter in front of the amp on power up. This is just a 60-100 watt light bulb, wired in the hot side of your 117v line. This gives your amp cush and tells you if it's pulling too many g's(just kidding about the g's). Anyway, I use 60 wat for two tube amps and 100 watt for 4 tube amps. If the light bulb flairs for just a second, and then goes to dim glow, you're pulling marginal current. If it glows bright, like a well lit bulb, you are pulling too many amps and there is a problem. It's great for keeping from blow $3 fuses too. If it glows dim, THEN I fire it up for real. Here's what it looks like(if it posts')

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Mike Kaus (mm210)
Username: mm210

Registered: 05-2006
Posted on Thursday, April 14, 2011 - 03:29 pm:   

By the way, in case you don't know(not trying to insult anybody but I have NO idea of peoples knowledge) the narrow spade on the plug is SUPPOSED to be the "hot" side, of course, depending on the yutz that wired your outlet. I've had them wired in ALL sorts of config's, including some guys that thought that since the green wire was hot on their car at time that THAT muct be the hot side here too. THAT can get exciting.
Jeremy Shaw (jemshaw)
Username: jemshaw

Registered: 09-2006
Posted on Friday, April 15, 2011 - 06:17 am:   

Thanks mike, I actually have one of those, I used to use it before I got the variac. Head smack. I also have had interesting experiences with other peoples amateur house wiring not quite active to earth but unearthed and back to front. Thanks for info
Cheers