Author Topic: Changing pot values  (Read 746 times)

Grazza

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Changing pot values
« on: September 14, 2021, 03:44:10 AM »
Hi,
Probably a really stupid question, but I'm really new to this. I'm sourcing components for my first few builds and I'm having trouble finding 9mm PCB mount pots in 5kc.
Of I can't find them, how would it affect the circuit of I were to use 10kc pots instead, or would it be less destructive to just use 5kb pots, which I think I have seen around. Also had trouble finding 20ka and 25ka in the 9mm alpha pots.
Another component question too, would a 2.2nf cap in place of a 2nf cap be very destructive, I haven't looked at the schem yet to see where it is in the circuit.
Cheers.

Govmnt_Lacky

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Re: Changing pot values
« Reply #1 on: September 14, 2021, 04:44:25 AM »
First... Welcome!

Second, for the pot question, it really depends on you. You can try to use substitute pot values however, you may not receive the desired output or "reaction" that you are looking for. Usually, it is best to stick with the listed value.

As for the capacitor question, a good general rule of thumb is +/- 10%. As long as you stay within 10% of the value you should be good. Since 2.2nF is within the 10% range it should be just fine!

Good Luck  ;D

Zerro

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Re: Changing pot values
« Reply #2 on: September 14, 2021, 04:47:08 AM »
Pot values are depending on circuit - what they do here. So, show schematic for us to consider, what you would do with it.
"Nudíte se? Kupte si našeho cvičeného ježka! Pobaví vás svými veselýmí kousky!"

Aleph Null

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Re: Changing pot values
« Reply #3 on: September 14, 2021, 09:41:19 AM »
Depending on the circuit either a C10k or a B5k could work. You might find with the 10k pot that half of the travel is useless, or maybe very subtle, or maybe hard to control. With a B5k pot, the whole range of the pot will work, but you may find that most of the adjustment is in the last third of the travel. In some cases, it may be possible to change some other values to get the same behavior as the original design.

Is there a particular circuit you are planning to build?

Grazza

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Re: Changing pot values
« Reply #4 on: September 15, 2021, 02:11:33 AM »
Thanks for the info. I have a kokbox, krankosaurus and firebomb that I was planning to build. These were actually purchased over 10 years ago, and I started collecting components back then, but most of what I got was wrong. Long story short I ran into financial trouble and had to sell all my gear. I found these in the garage the other day and thought I had better give them a go.
Does anybody have any suggestions as to where I can find 9mm 5kc pots? Tayda was no good, I have trouble with mouser and digikey, blms didn't have them either. I'm after the ones that allow the PCB to sit vertically in the enclosure, not the right angled ones.

Aleph Null

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Re: Changing pot values
« Reply #5 on: September 15, 2021, 12:06:29 PM »
It looks like Small Bear has them.
« Last Edit: September 15, 2021, 12:08:50 PM by Aleph Null »

Bio77

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Re: Changing pot values
« Reply #6 on: September 15, 2021, 12:11:05 PM »
Yep, SmallBear has all the pots on your list except the 20kA.  I don't think I've seen that value in 9mm anywhere before, are you sure it isn't a 20kW?

Grazza

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Re: Changing pot values
« Reply #7 on: September 16, 2021, 02:16:49 AM »
Thanks heaps, I'll try small bear, I wasn't able to get it happening properly on my phone so I think I gave up. Will try a PC. Yes, definitely a 20k pot, haven't been able to find one, will just use a 25k, no Biggie. Thanks again for everyone's help.

wizestwizard

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Re: Changing pot values
« Reply #8 on: September 16, 2021, 06:43:58 AM »
Thanks heaps, I'll try small bear, I wasn't able to get it happening properly on my phone so I think I gave up. Will try a PC. Yes, definitely a 20k pot, haven't been able to find one, will just use a 25k, no Biggie. Thanks again for everyone's help.

Yeah, Smallbear is excellent for finding a lot of things, their site works very poorly on mobile devices in my experience though lol. Hard to actually add anything to your cart if I remember correctly? Good luck, let us know how it goes!