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  #1  
Old 23rd September 2013, 04:05 PM
willfal60
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Default Will Kit88 Amp

dear all
as i mentioned a little while ago .re amp running hot. i thought all was well
until sunday,the amp was piping hot ,you could not touch it at all.when you
turned the volume up it cut out and made a popping noise,then the volume
re-appeared only to cut again. as i have grandchildren running about i v,e
taken it out of service[on the wifes orders]i nearly threw it in a skip.so will lay
it up for a good while ,as a pensioner i cant afford to get it repaired yet.is it
worth selling ,it has a lot of modifications done to it ,sowter uo82s and a load
of other quality parts. i,m just a bit disallusioned with it.
i will await your kind replies.
best regards
will
[dundee]
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  #2  
Old 23rd September 2013, 06:04 PM
bob orbell bob orbell is offline
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Location: kettering northants.
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Default Re: amp

Hi Will, just been back to your post of August 4, are we to take it that you are using two pairs of speakers with the amp all running together?, if that is so you may well be stressing the amp, this may be the reason it is getting too hot and cutting out. BOB
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  #3  
Old 23rd September 2013, 07:55 PM
willfal60
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Default Re: amp

hello bob
i,m not using 2 pairs of speakers,the only thing i did was to fit 2 tung-sol
high grade 12au7 valves, the other valves are 4genelux kt88 and 2sylvania
6au6wc .could it be these tung-sol valves.i haven,t a bloody clue.
regards
will
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  #4  
Old 23rd September 2013, 09:04 PM
vinylspinner vinylspinner is offline
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Location: Near devizes in wiltshire
Posts: 107
Default Re: amp

Hi Will,

I would check the 12au7 valve, that is an ecc82 type, you need an ecc83 in the centre and 2 5687WB valves to the left and right.


regards

Nigel
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  #5  
Old 23rd September 2013, 09:12 PM
vinylspinner vinylspinner is offline
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Join Date: Jun 2006
Location: Near devizes in wiltshire
Posts: 107
Default Re: amp

Just checked the original thread and seen Richards pic, I was thinking WD VA88, the current model, please ignore my last post, but some pics may help here. Is it the same as Richards pic?

good luck

Nigel
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  #6  
Old 24th September 2013, 02:24 PM
willfal60
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Default Re: amp

hello again
the story so far
this morning i put amp back on and fitted all the valves it came with ,which
worked no problem.i switched it on and guess what ,it hummed ,made a
crackling noise and then blew up ,smoke everywhere and burning smell.
i think it is f????d !!!!!.
i,m a bit saddened with it because when it was working it sounded really nice.
that,s life as they say.
regards
will.
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  #7  
Old 24th September 2013, 02:25 PM
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Ali Tait Ali Tait is offline
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Location: Leeds
Posts: 937
Default Re: amp

Hi Will,

If you can post or bring the amp to me, I'll have a look at it FOC. Might take a wee while though, I've a couple of other projects on the go at the moment.
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  #8  
Old 24th September 2013, 03:57 PM
bob orbell bob orbell is offline
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Default Re: amp

Don't loose heart with Will, it won't be major, I am sure Ali can help.
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  #9  
Old 24th September 2013, 04:39 PM
willfal60
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Default Will Kit88 amp

dear all
would anybody have a wiring diagram for this kt88amp,ali tait has kindly
said he would look at it for me,which was very nice of him.
it has sowter uo82 trans and a lot of bespoke bits in it,i would think
somebody knows something about it.any help would be extremely greatful.
best regards
will
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  #10  
Old 24th September 2013, 06:30 PM
John Caswell John Caswell is offline
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Location: Wokingham, Berkshire
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Default Re: kt88 amp

Hi Will,
Over the years there were quite a few minor mods to this amp ie changing bias resistors on the O/P valves uprating the anode resistors on the ECC82 etc. Ali should know about them and a quick look in the FAQ will also help.
Circuits don't present a problem but the original assembly instructions might

John
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