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  #1  
Old 9th November 2016, 10:24 PM
davebms davebms is offline
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Join Date: Nov 2008
Location: ware ,herts
Posts: 203
Default vtl tt25

hello al,,l I have a pair of VTL tt25,, they occasionally used to blow a fuse
then after a while they would not fire up at all ,,they have been in a cupboard
for years !! so with dummy load +shorting plug wound one up on a variac (no valves fitted)
pop,, disconnect the HT from board , 510volts, with the HT leads taped up
valve in all heaters ok I've tested all the diodes all seems ok ,the electrolytic
caps all look original so im going to replace them all
will se what happens !!

dave
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  #2  
Old 22nd February 2017, 10:54 PM
davebms davebms is offline
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Location: ware ,herts
Posts: 203
Default Re: vtl tt25

hello all ,, well a complete fail !!! with new caps and variac pop,, with transformer out of the amp , 520v ht 30v bios. 7.5 heater,, with clip leads the ht comes up ok , bios on its own, ok, with both fuse pops. ive taken the transformer out of the other,, working amp, that will power up both amps
so it was not the caps got to be a short ht to bias winding ,,I wanted to get them working and sell them to fund other audio stuff)

dave
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  #3  
Old 23rd February 2017, 10:41 AM
Richard Richard is offline
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Join Date: Dec 2005
Location: Notts
Posts: 4,600
Default Re: vtl tt25

Sorry to hear that Dave. You could still offer them as a project
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