Author Topic: Are chinese 10 turn pots any good?  (Read 3222 times)

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Offline ivan747Topic starter

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Are chinese 10 turn pots any good?
« on: August 20, 2017, 10:54:59 pm »
I'm asking this question here in the Projects sub-forum because if I ask on the Metrology forum I'm going to get shot at...

Are those 6 dollar 10 turn pots from China any good? The intended application is retrofitting a DIY lab power supply with them. I'm looking at 10k pots, if that makes any difference.

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Ivan
 

Offline danadak

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Re: Are chinese 10 turn pots any good?
« Reply #1 on: August 21, 2017, 12:18:43 am »
On e would expect in datasheet a rotation lifetime spec, if thats your concern.


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Offline FlyingHacker

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Re: Are chinese 10 turn pots any good?
« Reply #2 on: August 21, 2017, 12:34:44 am »
I have gotten quite a few of the (presumably counterfeit) Bourns ten-turn pots from eBay. About 20% were defective, but always refunded. The others work perfectly. I wouldn't use them for mission critical stuff, but great for personal projects or experiments.
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Offline zeqing

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Re: Are chinese 10 turn pots any good?
« Reply #3 on: August 21, 2017, 04:43:41 am »
basically try but not rely On. different vendors provide different products.
 

Offline poorchava

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Re: Are chinese 10 turn pots any good?
« Reply #4 on: August 21, 2017, 06:30:01 am »
Depends on what you want to use them for. For adjusting some bias on a power supply or audio system - ok. For real metrology or critical stuff - not ok.
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Offline CopperCone

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Re: Are chinese 10 turn pots any good?
« Reply #5 on: August 21, 2017, 06:44:50 am »
their tempco is shit and their unstable. treat it like a 1 turn pot. maybe its ok for something you null every time you use, but that would imply your system has like a drift 10x worse then the pot. there are some threads about counterfit pots on eevblog already

i don't know who bochen is trying to fool, perhaps people that don't wear glasses
« Last Edit: August 21, 2017, 06:46:35 am by CopperCone »
 

Offline owiecc

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Offline bitseeker

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Re: Are chinese 10 turn pots any good?
« Reply #7 on: August 21, 2017, 11:51:25 pm »
From my experience, they do operate as 10-turn pots. However, the rotational torque required is much higher than a genuine Bourns. I haven't had any long enough to assess their longevity.
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Offline bd139

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Re: Are chinese 10 turn pots any good?
« Reply #8 on: August 22, 2017, 12:01:07 am »
They're crap! Killed one dead in a VFO in about a week and it drifted terribly.  It got replaced with the delay sweep pot (bourns 10 turn) nicked out of a dead Tek 465 that is older than me. That's still going 4 years later!

Proper bourns ones aren't cheap new but you get what you pay for.
« Last Edit: August 22, 2017, 12:02:44 am by bd139 »
 

Offline FlyingHacker

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Re: Are chinese 10 turn pots any good?
« Reply #9 on: August 22, 2017, 12:10:09 am »
Maybe mine were genuine. They have been functioning fine, and feel comparable to the genuine ones I have here.  :-//

I use one all the time, as it is to zero the Ohms range on my main giant meter VTVM.
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Offline edavid

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Re: Are chinese 10 turn pots any good?
« Reply #10 on: August 22, 2017, 12:20:04 am »
Are those 6 dollar 10 turn pots from China any good? The intended application is retrofitting a DIY lab power supply with them. I'm looking at 10k pots, if that makes any difference.

You can buy one for $1.50 and see for yourself: http://www.ebay.com/itm/1pc-3590S-2-103L-10K-Ohm-10-Turn-Rotary-Wire-Wound-Precision-Potentiometer-Pot-/132283650630

BTW, 10 turn pots are very inconvenient and annoying on a lab supply.  It's better to have coarse and fine pots, or an encoder with software acceleration.
« Last Edit: August 22, 2017, 03:08:48 pm by edavid »
 

Offline drussell

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Re: Are chinese 10 turn pots any good?
« Reply #11 on: August 22, 2017, 03:14:47 am »
Pretty much any time you have to ask "is the cheap Chinese version of X any good", the answer is NO!

(Though, I suppose, there may be exceptions where they may be good enough for most usage...)
 

Offline Rbastler

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Re: Are chinese 10 turn pots any good?
« Reply #12 on: August 22, 2017, 06:16:27 am »
I used some and from ten, one did brake with out reason to me. So I'd say thats pretty good for the price of 1.5€ a piece. I woudnt use those as replacements in some test gear, but they are certanly ok for your own projects.

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