Author Topic: Activator PJ - Filter Pot has Loose Shaft - disrupting output  (Read 104 times)

keurosix

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I have an Activator PJ set up in a project bass that has the Vol - Vol - Filter set up with added 3 way Q switch. The Filter sweep knob seems to have a loose shaft, and when I turn the knob, it makes a thumping sound in the speakers, and even cuts out. I replaced the 9V battery with a fresh one, and flipped the Q switch, and changed the position of the volume knobs, but those function perfectly. Is there a way to tighten the shaft inside this pot? Or is it in need of a replacement?
« Last Edit: July 21, 2025, 10:50:33 AM by adriaan »

edwardofhuncote

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Re: Activator PJ - Filter Pot has Loose Shaft - disrupting output
« Reply #1 on: July 21, 2025, 02:49:44 AM »
Yikes, the tiny-font Gremlin sneaked in here!

I have an Activator PJ set up in a project bass that has the Vol - Vol - Filter set up with added 3 way Q switch. The Filter sweep knob seems to have a loose shaft, and when I turn the knob, it makes a thumping sound in the speakers, and even cuts out. I replaced the 9V battery with a fresh one, and flipped the Q switch, and changed the position of the volume knobs, but those function perfectly. Is there a way to tighten the shaft inside this pot? Or is it in need of a replacement?


There...   ;)  maybe somebody can help with this one. I don't think those pots are serviceable. Maybe someone else has an idea.

mica

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Re: Activator PJ - Filter Pot has Loose Shaft - disrupting output
« Reply #2 on: July 21, 2025, 07:42:56 PM »
Can you post an image of your electronics? Generally something like you describe isn't repairable, but it might be helpful to see the circuit, especially if you can show it installed in the instrument

keurosix

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Re: Activator PJ - Filter Pot has Loose Shaft - disrupting output
« Reply #3 on: July 22, 2025, 07:03:34 PM »
Update.. It's not a loose shaft. Seems to be an issue with the PC card the pot is attached to. I removed the nut and washer to let the pot dangle outside the open back, and when plugged in it seems fine. If I touch the edge of the pc card, it has that muffly sound that interrupts the output. I tried to do a video but the camera's mic is horrible. I'll have to try a recording through my Audio interface on my computer

keurosix

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Re: Activator PJ - Filter Pot has Loose Shaft - disrupting output
« Reply #4 on: July 22, 2025, 07:17:02 PM »
Tried posting picture...