ACA Mini potentiometer pins

Official Court Jester
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value per se, is separate issue

anyhow, your choices are yours, no one should dispute that

I also had builds following "sculpture building" approach, simply for pure pleasure of combining things not just technically but also visually

so, as they say - whatever shakes your cage, that's your cage :rofl:

(just ignore a fact that - if you bend those two outer pins with tweezers, there is no visible difference in aesthetics, when trimpot is soldered on pcb)
 
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Hi, also in my kit there are "wrong trim pots", which do not fit corretly the board holes.
I wrote to diyaudiostore, but in the meanwhile I'm looking for correct trim pots in online stores. Could some one give me the correct product series/ID?
thanks!!

PS: mine are BOURNS 3386 series, CW type
 
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I assume you're looking for the 2k pot. If so, then that looks fine.

BTW, it seems the lead-free/ Rhos version is somewhat cheaper ( https://www.mouser.ca/ProductDetail/Bourns/3386P-1-202LF?qs=m2uG/FdTAPXuAmTNGpORnw== )

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The DIY fix to installing the pots included in the most recent batch of kits is to first make a 90 degree bend on the ends of pins 1 & 3, about 3-4mm, then bend the pins flat against the body of the pot. They will then line up with the hole and fit darn near perfectly onto the board.

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Question for @WBS : Are the trim pots in the current batch of ACA Mini completion kits the 2K version? Maybe the better fitting trim pots that @Nelson Pass sent to me were 1K.

The reason I ask is that I bought a second kit and built it two days ago. I folded the pins as you showed, and the fit was fine. But while adjusting VB and VO I find these pots are really touchy. The slightest pressure can have a big effect. The trim pots Nelson sent to me seem less touchy.

In any case, the trim pots that come with the current kits work just fine.

Aside: My second amp warms up much faster than the first one, and VB seems to stay more stable too. A mystery to me. [I have yet to listen to the second amp. I want to spend another day, at least, making sure VB and VO stay put.]
 
@WBS : Thanks for the quick reply. Being a novice builder, I have a lot to learn, and I enjoy learning tremendously. Not to mention listening to a truly state of the art amplifier in my system, as I am currently doing while eating dinner and giving ACA Mini more "time on the bench" to make sure VB and VO are where I want them.
 
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be a Chicken, as ZM

use multiturns
Actually, tha brings an interesting point. Is there a particular reason that Pass Labs uses single turn pots? I have heard of "spring back" with multiturns but have never experienced it myself. Having adjusted single turns on sensitive circuits, you have to find your zen before you pick up the screw driver...
 
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Official Court Jester
Joined 2003
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at PL, they're Masters

I'm mere Broom-holder in Monastery


I've seen enough multiturns in professional equipment and medical; if in doubt, you can always put tiny blob of nail-polish on screw side, at least to keep that from spinning through fool moon night

or is it full moon?

:clown:
 
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Has anyone seem this (or similar) type of trimmers?

https://www.mouser.ca/ProductDetail...s/Y40535K00000J0L?qs=OeYRSXBqOJvfzSbUXow/xw==

These are obviously way too rich for my blood, but what I found interesting is that the datasheet seems to indicate that the 'standard' trimmers we normally use are not monotonic as a function of the position of set screw. That said, I've never had an issue with El-Cheapo cermet multiturn trimmers in my builds.

Cheers,
Dennis