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challenger volume issue [message #18191] Sat, 16 February 2013 15:08 Go to next message
gwedo1971 is currently offline  gwedo1971
Messages: 9
Registered: February 2013
Location: Taylorville, IL.
Junior Member
First off i would like to say hi to everyone. im new here and thanks for having me, well i just got my hands on a very super clean almost mint kustom challenger combo (black) with cover and footswitch its been hiding in a closet since 1973 (he thinks anyhow) i got it home tryed it out and it works sorta typical rca jack corrosion and so on any way tor it down new switch, grounded power cord, cleaned pots and jacks, and all works great other than the volume does not turn down all the way, pulled the pot hand cleaned it put it back and same thing puled it again got a new cts 250k had to swap the d shaft into it tests good re-installed and same thing volume just dont go to zero is this common for these amps or do i have somthing else wrong.
thanks
eric

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Re: challenger volume issue [message #18192 is a reply to message #18191] Sat, 16 February 2013 15:46 Go to previous messageGo to next message
Kustom_Bart is currently offline  Kustom_Bart
Messages: 601
Registered: October 2010
Location: Greenville, MichiGUN
Senior Member
YES! They got the name correct on them, they are a challenge to keep going. I have owned a bunch of these, I love them, but I hate them too. They are one of the best sounding small amps made by Kustom, but they are not reliable.

They have a funny way of letting you down when you need them. Mine would work for 5-6 months and then go to crap. I would get it repaired and then something else. then some thing else. and then and then and then and then. I would get it fixed and sold it. I had 4 at one time and found the most reliable one and kept it and the rest went. I saved the mint condition one.

[Updated on: Sat, 16 February 2013 16:02]

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Re: challenger volume issue [message #18193 is a reply to message #18192] Sat, 16 February 2013 16:03 Go to previous messageGo to next message
gwedo1971 is currently offline  gwedo1971
Messages: 9
Registered: February 2013
Location: Taylorville, IL.
Junior Member
it works great and sounds awesome its just odd that it wont turn all the way down i found a schematic so ill be pulling the poor thing apart again to do some testing also i see people saying its 25 watts but this schematic says its 50 Shocked

[Updated on: Sat, 16 February 2013 16:04]

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Re: challenger volume issue [message #18194 is a reply to message #18193] Sat, 16 February 2013 16:08 Go to previous messageGo to next message
Kustom_Bart is currently offline  Kustom_Bart
Messages: 601
Registered: October 2010
Location: Greenville, MichiGUN
Senior Member
I have schematics if you need them as well. It is 50 watts RMS 25 watts actual. 25 watts that will tear your head off for sure. You can gig any where with one or a K50 for sure.

[Updated on: Sat, 16 February 2013 16:11]

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Re: challenger volume issue [message #18195 is a reply to message #18194] Sat, 16 February 2013 16:12 Go to previous messageGo to next message
gwedo1971 is currently offline  gwedo1971
Messages: 9
Registered: February 2013
Location: Taylorville, IL.
Junior Member
ya a schematic would be cool the one i have is a little hard to read in spots and maybe its the wrong one, thanks

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Re: challenger volume issue [message #18196 is a reply to message #18195] Sat, 16 February 2013 16:32 Go to previous messageGo to next message
Kustom_Bart is currently offline  Kustom_Bart
Messages: 601
Registered: October 2010
Location: Greenville, MichiGUN
Senior Member
PM me your e-mail address and I will send it

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Re: challenger volume issue [message #18197 is a reply to message #18196] Sat, 16 February 2013 16:53 Go to previous messageGo to next message
gwedo1971 is currently offline  gwedo1971
Messages: 9
Registered: February 2013
Location: Taylorville, IL.
Junior Member
cool, its sent

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Re: challenger volume issue [message #18198 is a reply to message #18197] Sat, 16 February 2013 16:59 Go to previous messageGo to next message
Kustom_Bart is currently offline  Kustom_Bart
Messages: 601
Registered: October 2010
Location: Greenville, MichiGUN
Senior Member
They are sending now in .PDF format

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Re: challenger volume issue [message #18275 is a reply to message #18191] Mon, 25 February 2013 23:08 Go to previous messageGo to next message
gwedo1971 is currently offline  gwedo1971
Messages: 9
Registered: February 2013
Location: Taylorville, IL.
Junior Member
well my diodes came got them put in added the one to the output driver ic and guess what now the amp dont work at all no hum no crackle no sound nothing took the extra diode out still nothing Sad

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Re: challenger volume issue [message #18276 is a reply to message #18191] Tue, 26 February 2013 00:15 Go to previous messageGo to next message
chicagobill
Messages: 2005
Registered: April 2003
Senior Member
What diodes? Where did you add them and why?

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Re: challenger volume issue [message #18277 is a reply to message #18276] Tue, 26 February 2013 00:17 Go to previous messageGo to next message
gwedo1971 is currently offline  gwedo1971
Messages: 9
Registered: February 2013
Location: Taylorville, IL.
Junior Member
rectifier diodes and then the schematic said to add one between pin 8 and pin 9 on the se540L

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Re: challenger volume issue [message #18279 is a reply to message #18191] Tue, 26 February 2013 11:54 Go to previous messageGo to next message
chicagobill
Messages: 2005
Registered: April 2003
Senior Member
I must have an older schematic, there's nothing about a diode between pins 8 and 9. In fact pins 8 and 9 are connected together on mine.

Well, the amp was working before, so it's something that happened when you did the work. Go back and double check everything that you did and hope that the 540 chip is still okay.

Carefully take voltage readings and compare them to the schematic.

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Re: challenger volume issue [message #18280 is a reply to message #18279] Tue, 26 February 2013 12:05 Go to previous messageGo to next message
gwedo1971 is currently offline  gwedo1971
Messages: 9
Registered: February 2013
Location: Taylorville, IL.
Junior Member
no bill the 540 is dead, i got nice clean signal all the way to it and nothing after, i got a schematic from bart and don that has updates on it my voltage is about a volt high but i think thats the building i live in it runs a little hot right out of the wall, dug the net for some time last night working on a replacement option just have to research it a little more

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Re: challenger volume issue [message #18281 is a reply to message #18191] Tue, 26 February 2013 13:14 Go to previous message
chicagobill
Messages: 2005
Registered: April 2003
Senior Member
That's a drag. I see them on eBay NOS all the time. Maybe Bart will have some more options, as he is Mr. Challenger.

If you do replace it be sure to use the best heatsink that you can fit on it, as it is running at maximum voltage levels in this circuit.

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