K250-1 repair [message #17227] |
Sat, 23 June 2012 08:14 ![Go to next message Go to next message](/FUDforum/theme/vk30/images/down.png) |
retrorod
Messages: 5 Registered: June 2012 Location: Outer Banks, NC
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Junior Member |
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Hey all! I,m new to this forum but have been doing amp repairs for several years. I have not worked on Kustom before, so I will pick the Kustom gurus' brain.
This is a non-functioning head that a young lad, tried to 'fix' and then cast it aside. The power switch is busted and a few wires were left unconnected with no markings. Three wires were pulled from the Molex connectors. I have an almost indentical salvage chassis that I have been able to figure out which positions that the wires need to go back in the plugs.
Is there a trade secret way of making a good connection and perhaps soldering those wires back into the plugs....or is it best to ignore the plug and hardwire them.
I am going to pull a power switch from my parts chassis.
I see no burnt or scorched parts in the amp and am hoping for an easy fix!
Never hurts to be optomistic.
There is a wealth of info in this forum....thanks!
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Re: K250-1 repair [message #17229 is a reply to message #17227] |
Sat, 23 June 2012 11:15 ![Go to previous message Go to previous message](/FUDforum/theme/vk30/images/up.png) ![Go to next message Go to next message](/FUDforum/theme/vk30/images/down.png) |
chicagobill
Messages: 2005 Registered: April 2003
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Senior Member |
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Welcome to the place. Pleat, he noted it was a K250-1 head in the topic heading, so it's a metalfront.
The connectors are often the source of multiple problems, but if you clean the contacts and keep them tight they will work just fine. That being said, removing them and hardwiring the boards together works just as well. I like being able to pull out a board to swap it with a working one for testing, etc.
Overall Kustom amps are very well designed for their time, and you should have no problem fixing it up. The only parts that will be hard to find are the 739 dual opamps and as Pleat has already mentioned, the blue push/push Licon power switch.
If you need the schematics for your amp, PM me and I can email them to you. Again welcome!
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Re: K250-1 repair [message #17230 is a reply to message #17229] |
Sat, 23 June 2012 15:34 ![Go to previous message Go to previous message](/FUDforum/theme/vk30/images/up.png) ![Go to next message Go to next message](/FUDforum/theme/vk30/images/down.png) |
retrorod
Messages: 5 Registered: June 2012 Location: Outer Banks, NC
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Junior Member |
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Thanks for the quick responses. Yes, the restore amp is the metal front,blue button bass head from 1974. My scrap chassis is a 1971 or 72 metal front 250 guitar head with reverb.
Both Licon switches seem OK in the the scrap chassis. Both are damaged in the repair amp. They look pretty complicated compared to other on/off switches....Very interesting.
I can,t tell you how many times I was contemplating just thowing the scrap head out....and NOW I have a purpose for some of the parts.
The real question from me is the best way to secure wires into the metal sleeves of the Molex plugs? I will experiment....
I'll try to post my progress and I am sure to have more questions!
[Updated on: Sat, 23 June 2012 16:18] Report message to a moderator
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Re: K250-1 repair [message #17231 is a reply to message #17230] |
Sat, 23 June 2012 20:53 ![Go to previous message Go to previous message](/FUDforum/theme/vk30/images/up.png) |
pleat
Messages: 1454 Registered: June 2004 Location: Belding, Mi
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Senior Member |
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Boy, I guess I'm overdue for new glasses. Your right, I completely missed that it was a K250 head. The molex plugs idea came to be with the slant metal face amps. Kustom liked the idea that circuit boards with the molex plugs simplified assembly and were promoting that in the event an amp had a failure, a dealer could just unplug the pre amp and install a new one from stock and get the customer back on the road in a few minutes. The downside to that theory was most problems were not in the pre amps but in the power amps and they soon found out that the connectors would make and break contact causing more repair issues.
pleat
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