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Kustom 100 [message #17283]

Thu, 12 July 2012 12:25

Joeamp
Messages: 4
Registered: July 2012
Location: NYC / Long Island

Junior Member

Hi all
I have some of Godfrey Townsends Kustom 100-2 PC104 heads here. He's on the "Happy Together Tour" with The Turtles & Micky Dolenz and has aquired one of these Kustom 100 (K 100-2 PC104) heads and speakers cabs in ever color.
Most seem to have the same problem: When you turn the reverb control up the reverb gets louder and the dry signal disappears along with most the volume.
Sadly I myself lost the schemetic I had in a laptop theft. Im guessing one of these infamous tanatlum caps let go.

From what I remember there was a revision to these amps.
Looking for info, I have 1000s of schematics to trade.
It best to email me direct at "joe.ampNOSPAM "at" verizon dot net.
(remove the nospamming refs)

-Joe L

-Joe Amp

[Updated on: Thu, 12 July 2012 13:11]

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Re: Kustom 100 [message #17284 is a reply to message #17283]

Thu, 12 July 2012 18:59

chicagobill
Messages: 2005
Registered: April 2003

Senior Member

Welcome to the place Joe. Unfortunately what you describe sounds fairly normal. Unlike a Fender circuit, the Kustom reverb control acts like a balance control full CCW dry signal only, full CW wet signal only. I know that the Thomas Organ Vox heads do the same thing.

There still may be something wrong with some of the amps. How different do they act?

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Re: Kustom 100 [message #17285 is a reply to message #17283]

Thu, 12 July 2012 21:07

rodak
Messages: 511
Registered: October 2001
Location: Georgia

Senior Member

I had never heard of Godfrey Townsend (I don't get out much, I guess), but your post led me to his website, and I really enjoyed reading about his gear history. Not much in the way of Kustoms there, but lots of other cool stuff.

Bill, you're right about how the reverb control works, but note that he also says he loses most of the volume with the reverb maxed - that doesn't sound right, does it?

www.combo-organ.com

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Re: Kustom 100 [message #17286 is a reply to message #17283]

Fri, 13 July 2012 09:00

stevem
Messages: 4733
Registered: June 2004
Location: NY

Senior Member

Why you would need to max out the verb unless your are playing 60s Ventures stuff, or surf music is beyond me anyway!

A faster fix might be to just place a reverb stomp box in the signal chain, but I will take a look(schematic wise) and a listen to my K100-2 and see what might go south, or maybe a easy mod that might help out and balance things out better.

One thing while we are on this subject is that last week I used my 66 Frank head and noticed that like the K100 head this whole post started with, this heads reverb channel dropped off in volume and in treble responce big time as the reverb was opened up passed 1/3.
I opened the amp up and in looking over the schematic I found that the resistor that should have been removed from the circuit when the reverb board/effect gets installed was never removed before the amp left the factory!!
I have yet to pull the amp apart to fix that, but when I do will post the results, it also makes me wonder how many more Of the Frank heads got sent out being built the same way?

[Updated on: Fri, 13 July 2012 09:02]

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Re: Kustom 100 [message #17289 is a reply to message #17283]

Sun, 15 July 2012 16:31

Joeamp
Messages: 4
Registered: July 2012
Location: NYC / Long Island

Junior Member

Thanks all, It def not normal
I just looked:
Head 1
The dry signal drops off as soon as you get into any part reverb control range (no dry from counterclockwise to clockwise). The Reverb appears immediately and only gets "slightly" louder toward full clockwise..Amp has no power
Reverb "full off" the amp is normal, full power.

Heads 2 and 3
Same as above but the dry signal is just audible at best (counterclockwise) You cant shut the reverb off at all but that likely the N.C. contact on the Footswitch phone jack

Its something in the mixing scheme I'm still looking for my paper schematics I have 1000s of papers and parts in file cabs and parts drawers dating back to 1976---Its nuts.
BTW Godfrey will also be out with "Son's of Cream" I will send a link this to his phone this week. I'm sure he will drop in when he's free.
Rodak---GT is using a Marshall on both tours

-JL

-Joe Amp

[Updated on: Sun, 15 July 2012 16:48]

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Re: Kustom 100 [message #17290 is a reply to message #17283]

Mon, 16 July 2012 06:35

stevem
Messages: 4733
Registered: June 2004
Location: NY

Senior Member

Head 1 sounds like the reverb pot R171 which a 15k control is bad, but with that being said I would first stock up on 10uf 50 volt non electrolytic caps and replace
c119
c143
c125
c126
c128
c130, and c114
Than I would check R160 which is a 100k and make sure its within its 10% range.

I would replace Q108 the reverb and dry mixing transistor and check out any of the 1% resistor around the reverb circuit.
I would also ohm out all the reverb pans (both inputs and outputs), they should check out anywhere from 175 ohms to 200.

If c119,c143,c128 or c130 are leaky then they can throw off the bias of the transistors they couple to.

If all the reverb pans check out I would place a dab of silicone sealer on all the wire ends, where the enter the small coils and also where they solder to the RCA jacks as they always seen to break off sooner or latter and a good dab of sealer will stop travel vibration from doing that!

[Updated on: Mon, 16 July 2012 06:39]

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Re: Kustom 100 [message #17291 is a reply to message #17290]

Mon, 16 July 2012 14:42

Joeamp
Messages: 4
Registered: July 2012
Location: NYC / Long Island

Junior Member

Thanks will do I'm making up a Mouser electronics order this week I'm also out of 68uf from working on two k200s both had one shorted on the driver rail.
I'm still trying to find a K100-2 (PC-104) schematic or at least a board layout.

-Joe

-Joe Amp

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Re: Kustom 100 [message #17292 is a reply to message #17291]

Mon, 16 July 2012 17:02

Kustom_Bart
Messages: 601
Registered: October 2010
Location: Greenville, MichiGUN

Senior Member

Schematics sent

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Re: Kustom 100 [message #17293 is a reply to message #17291]

Mon, 16 July 2012 19:59

Joeamp
Messages: 4
Registered: July 2012
Location: NYC / Long Island

Junior Member

William sent me a Schematic (Thank You William)

Steve M:
It took 5 minutes C119 is leaking screwing up the bias on not one but several transistors (if not already damaging them)
--Both amps
I'm going to pull out the Ungar desoldering station and replace all the 1uf and 10uf caps. Now that I am looking close they are all dried out and failing or about to fail in different ways.
After 45 years A full refurb of the board is going to be the only way to go for reliability and prevent bigger problems.
The K100s were made when solid state was in its infancy, Its time.

-Joe Amp

[Updated on: Mon, 16 July 2012 20:42]

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Re: Kustom 100 [message #17294 is a reply to message #17283]

Tue, 17 July 2012 07:21

stevem
Messages: 4733
Registered: June 2004
Location: NY

Senior Member

You can`t blame any electrolytic cap for going south after even 30 years no less 45!
If you look at the build quality of kustoms once they got into the K200A serise and then look at the short lived SS Fenders and Acoustic amps of around that era, the difference is plain to see, I only which they went thru the added expence of putting component numbers on their circuit boards!

If any of the amps look like there was work done to the + and - 8 volt regulator section I would replaces the caps in those sections also, as if any of the transistors have shorted in those sections the caps where hit with way more than there rated voltage.

[Updated on: Tue, 17 July 2012 07:22]

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Re: Kustom 100 [message #17295 is a reply to message #17294]

Tue, 17 July 2012 09:42

Kustom_Bart
Messages: 601
Registered: October 2010
Location: Greenville, MichiGUN

Senior Member

I agree Steve, the Kustoms are a far superior built product as they used all quality parts. I have never had 1 head that has the problems of all of the heads that you have. I guess I am just lucky or something. Maybe it could be a climate thing too, but every head that I have, I bet 95% of them have never been touched inside. That is saying something about Kustom. My K200A-2 head is perfect too (I guess I got a good one)...lol! It is red though so that must be why with a red 2 x 15 altec cab nearly mint!

Long live Kustoms!

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Re: Kustom 100 [message #17424 is a reply to message #17291]

Wed, 29 August 2012 19:25

jassman
Messages: 9
Registered: August 2012
Location: montreal

Junior Member

Hi Joe....just saw your post looking for PC104 schematics. I have it if you're in need. I'll gladly send you a copy. Email me at jassman862@hotmail.com
I'm in need of PC502, PC602, PC702, PC102: these are for the K200a-5 amp.
Know where I can get these Joe?
Regards,
Michael

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