JMK

Pultec 1A clone high boost filter cap leaky?
« on: August 12, 2019, 08:59:36 PM »
Hi !

I have problem with the high boost on a 1A clone.
When i turn the high boost its not a smooth response, and i have to turn the knob fast all the way up to to 10 to get it to respond.
Its also scratching when i turn the knob (with no audio playing through of course)
It seems like a leaky cap in the high filter section its affecting  all KCS selections, could it be .0033?
Good old paper oil caps   ::)

Help is much appreciated!




radardoug

Re: Pultec 1A clone high boost filter cap leaky?
« Reply #1 on: August 13, 2019, 12:39:39 AM »
If its a correct clone the filter section is between two transformers, and there is no d.c. on the filter parts. Sounds more like you just have a crapped out pot.

CJ

Re: Pultec 1A clone high boost filter cap leaky?
« Reply #2 on: August 13, 2019, 02:04:49 AM »
what kind of cap? sprague black beauty? astron? cornel dublier? change it out and see what gives,
If I can't fix it, I can fix it so nobody else can!
Frank's Tube Page: www.mif.pg.gda.pl/homepages/frank/vs.html
Guitar Amps: http://bmamps.com/Tech_sch.html

JMK

Re: Pultec 1A clone high boost filter cap leaky?
« Reply #3 on: August 13, 2019, 06:09:50 AM »
Hi,

Its an old black beauty  ::)

What i thought was that there is maybe one cap that is charging d.c sorry leaky was not the right word.

So it could be the .0033 in the filter section acting up?

radardoug

Re: Pultec 1A clone high boost filter cap leaky?
« Reply #4 on: August 13, 2019, 06:00:05 PM »
3 steps.
1/ Buy a cheap component tester, 20 bucks.
2/ Test the component you are not sure about.
3/ Replace as necessary.
Its not really rocket science.


 

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