WOPL 400 Build Problem!

nadude98

nadude98

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#161
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#161
laatsch55 said:
No pics on the A60 restore?????


Turn on/off thump was history with the Rev "C" board, you definitely have a problem......
Click to expand...
Let me double, triple check that ... I was so caught up in everything else. I just thought of it. I'll take a look at it tomorrow.

I'll take some pics then. It's been a piece of work. Got it from shopgoodwill for less than $50. It looked nasty. Cleaned it (definitely came from a heavy smokers home), deoxited it. Then discovered it had a bad phono input switch (NLA) I took the switches apart. Pics somewhere on here or AK, I posted trying to find a replacement. Took apart the bad switch, plastic tit worn off so no way to fix, so I ended up swapping switch position with AUX. Used the amp for about 2 weeks continuously on, sounded darn good with my Thiel's! A lot better than the Pioneer SA-6500. Well it eventually dropped a channel. So I've been doing a recap and some testing. I guess I should have taken some pics after I pulled the heat sink and all outputs.. It has definitely been hot! One of the big supply caps has been leaking... etc. I'll start a thread later, I'm whupped!
 
nadude98

nadude98

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#162
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#162
laatsch55 said:
As you can see now, you don't need much for test equipment until you have a problem......especially when it's frequency or power dependent.....
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Yep... might be some good news coming my way... one of my wife's brothers was a tech and owned an appliance-tv store. He passed away a few years ago and his stepson inherited the place. He is a trucker and is on the road right now, but at some point she is going to try and talk to him. All her brothers equipment is sitting on the workbench at the store where he left it. Scopes, freq generator, variac......etc... supposedly he was a pretty good tech. Bad part is the stepsons wife is a real bitch and she runs the store. Supposedly she would try and bilk us for every dollar she could get.. as in "new" prices.

Well, goodnight!
 
nadude98

nadude98

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#164
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#164
laatsch55 said:
OK, Nite Bud...
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Had a busy day, I'm going to try a couple of things tomorrow and post what's up!

I had in take a friend of mine over to another friends that is an antique dealer and is always picking stuff up and selling. Got my buddy a pair of Altec Lansing Model 14's.. sweet deal! Only $250, wish I would have had the bucks..!

Goodnight folks!
 
nadude98

nadude98

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#166
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#166
He still has it... in my one conversation with him since he has had it, he basically was monitoring it while playing it. Also inserted a 400hz signal and said it was perfect. Played it and watched it on the scope everything was good. He only has 150watt load resistors and high efficiency speakers so he never really tested it under any stress and he didn't test the bias so I asked him to do that and that it only started distorting and failing under load.. still waiting!

Heading to Phoenix the 12th woohoo!!! Know anyone out there that can look at this amp?
 
nadude98

nadude98

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#174
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#174
Well I just got a call from the shop that's been looking at the amp for me. He can't find anything wrong with it. He can only drive it to 150 watts, that's what his dummy load is. If he can't I don't think I'll be able to. Is there someone that can please help with this?
 
nadude98

nadude98

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#177
Latest update... I got the amp back. Before I went to hook it back up I ran some test on the pre-amp. I should have tested it before but I just wouldn't believe it could be it as I have been using it for about 2-3 years ever since I had had it restored by Carver Audio Repair.

I need to do some research but I have about 250-270mvdc on the left channel whereas the right channel is reads .0002mvdc

So apparently I did a good job building the amp..... WooHoo! Thanks everyone for your help...! Now I'll to start a thread on trying to fix the preamp... although I think it might be over my abilities! And/Or buy a different preamp, though I am partial to my Carver C4000!
 
nadude98

nadude98

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#179
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#179
laatsch55 said:
That's a bit much DC offset leaving the pre amp...
Click to expand...
Understatement! LOL

Yeah! Well the guy that had my amp said he couldn't find a thing wrong and when he said the bias didn't do as I was seeing when I plugged the preamp I figured I should look at it. So I must have done a bang up job on the amp..... :happy2:
 
nadude98

nadude98

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#180
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#180
I want to say "it can't be that simple" but maybe it was. I replaced the dethump fet's and it seems to be okay. It looks like the factory fix was done as the fet's were mounted in the position they would be in if they had been replaced with ? BC39 J112's?
 
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