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NEC TG-16/TE/TurboDuo => TG/PCE Repair/Mod Discussion => Topic started by: Black Tiger on November 25, 2012, 05:56:39 AM

Title: What is this part?
Post by: Black Tiger on November 25, 2012, 05:56:39 AM

I'm asking this here since the people monitoring this section will know for sure.


(http://superpcenginegrafx.net/misc/sgrgb.jpg)



What are these knobs called and where is the best place to buy a new one? Did the knob part for the left RGB dial just pop off, or did something snap off that would require more than the white dial to be replaced?

Title: Re: What is this part?
Post by: ProfessorProfessorson on November 25, 2012, 06:17:54 AM

Pot. You'll need to replace the busted one.

Title: Re: What is this part?
Post by: DarkKobold on November 25, 2012, 06:20:09 AM

They are potentiometers, or variable resistors. I don't think you can just buy a knob, because they are proprietary. You'll need to know the range of the pot, by holding a multimeter to the two sides and adjusting it to Rmax. That will tell you the replacement you need.

That said, I don't think the missing knob should be affecting the circuit. It is just there to help you adjust the pot with a screwdriver.

Title: Re: What is this part?
Post by: bust3dstr8 on November 26, 2012, 08:03:33 AM

 search for 0.5K/500ohm trimmers

Title: Re: What is this part?
Post by: thesteve on November 26, 2012, 04:54:43 PM

i read it as 100K

Title: Re: What is this part?
Post by: Fidde_se on November 28, 2012, 05:25:05 AM

Hi, it's actually 1M Ohm.

There are different physical sizes but they have a standard and this would be either 10mm in diameter but I think it's the 6-7mm version as it looks like it relatively to the solderings. any how, it's "top adjust" and "single turn" and also of course "a hole throw component" (obvious but likewise, as important)

I would say this one is a very good alternative
http://www.ebay.co.uk/itm/260979479197

You can choose 1M Ohm in the list there.

Title: Re: What is this part?
Post by: bust3dstr8 on November 28, 2012, 07:00:59 AM

Black Tiger has them turned, if you reset the flat edges on the body and dial to face down it reads 501.


http://www.aliexpress.com/store/product/20pcs-500-Ohm-trimmer-trim-pot-single-turn-top-adjust-Variable-resistor-501-free-shipping/107624_576570542.html

Title: Re: What is this part?
Post by: Fidde_se on November 28, 2012, 07:23:59 AM

You are spot on, 1M Ohm is ridiculously high as this is only there to dampen some RGB signals, 500 Ohm it is...

Title: Re: What is this part?
Post by: thesteve on November 28, 2012, 07:35:11 AM

lol, 1M would be rather high