Trim pot Question

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Trim pot Question

knight_yyz
Hey guys, I just bought a pre made PCb for a pedal.  The schematic calls for a 470K trim pot. Would it hurt to use a 500k instead?  They are variable by turning the screw so I'm assuming it should be ok, but then again I'm not an expert.  I'm having a hard time finding one in the right style for the board pinout.  Looks like it needs to be the ceramic box style with the little brass screw.  

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Re: Trim pot Question

Synsound
That would work fine. Ive never used the style you mentioned but i believe they are easier to fine tune as the screw is multi turn. if you are having a ton of trouble finding one to fit the pcp you could always run wires from the pcb to a tiny vero daughterboard and put what you have on there.
Give a man a match and he'll be warm for a day.
Set a man on fire and he'll be warm for the rest of his life.
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Re: Trim pot Question

knight_yyz
The board I bought was made for vertical carbon trim pots.  I have never seen that style in vertical.  I think I have something that will fit though.  The leg patern is very close.  Now to see if I have the proper resistance though.  

it wan't these


hopefully this will work
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Re: Trim pot Question

knight_yyz
Found what I needed at digikey.  
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RE: Trim pot Question

Chris60601
This post was updated on .
Other worth mentioning vendors

Tayda - if you can wait a few weeks, prices are very good

Mouser - if you like digi, you'll like mouser. Fast deliveries too.

Smallbear - personally, my favorite. Prices are ok, fast delivery, geared towards pedal builders

Mammoth - priced ok, deliveries are ok, also geared towards pedal builders.

There are others but I find that I pretty much stay with these and in that order.
Yeah, 220, 221. Whatever it takes.
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RE: Trim pot Question

knight_yyz
Thanks Chris, I've been getting 90% of my resistors from work.  they are all 1% metal film.
For other stuff I go to Tayda first.  I check Newark sometimes, but they are either really expensive or really cheap so it's hit or miss for value.  I've digikey a few times and shipping is quick.  I just checked the mouser page and it would have saved me a buck or two if I had gone there, assuming their shipping prices are about the same as digikey.
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Re: Trim pot Question

Beaker
In reply to this post by knight_yyz
I think that what you are describing is a Bourns multi-turn trim pot, like this:



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Re: Trim pot Question

knight_yyz
i actually thought i was posting this.  I have these already but i'm not sure if they will fit the pattern in the board.  
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Re: Trim pot Question

motterpaul
s long as you get tabs 1, 2 and 3 on the right strip rows (keeping cuts in consideration) all trimpots are the same - shape doesn't matter.

On some you you need more turns - and always figure out the right screwdriver to use (Some like the one above need a round cover, other needs to be plastic because both sides of the pot are metal and a steel screwdriver will short them out.