what rating is this speed pot?

[karma67]

i would like to change the 2 speed potentiometers on my pioneer turntable,the markings on both pots are as follows, NOBLE KCS -004-0 B500 Ω A=G
anyone know what rating they are please?
https://s26.postimg.org/rgupot3yh/IMG_1215_1.jpg

[walpurgis]

Do they need changing Jamie?

[karma67]

well they work but i just want to rule them out in diagnosing my slight speed fluctuation

[struth]

500 ohm presumably.. test it on a meter. Trim pots. You should be able to pick them up easy enough. Unusual for them to be completely goosed. They can end up with wear points, usually just where you want it to be though

[karma67]

yes grant that's exactly the trouble,you get them set right then the strobe starts creeping to the left,adjust them and it creeps to the right,if you get it right it seems to just wobble,which is why i want to replace them to rule them out.
i think the problem i have is finding the right shaft length.

[struth]

The pots on my slatedeck (uses an old techy dd motor)were same. I cleaned them and worked them for an age ..made sure tge wipes were tight and got them set pretty good within a 2 turn a minute which is close enough. I used a fancy speed testing unit. Fires a light at the platter. Now set they are stable, so i just dont touch em lol. But need serviced/ replaced really, along with caps etc. But while its working so well i just left it til it plays up..


Maybe look for an old donor deck

[karma67]

this one looks like it will do, (I HOPE)

http://www.mouser.co.uk/Search/ProductDetail.aspx?R=PDB241-E425K-504A2virtualkey65210000virtualkey652-PDB241E425K504A2

[Qwin]

this one looks like it will do, (I HOPE)

http://www.mouser.co.uk/Search/ProductDetail.aspx?R=PDB241-E425K-504A2virtualkey65210000virtualkey652-PDB241E425K504A2

That's a 500Kohm pot you link to Jamie, I would measure the one you have to make sure its not just 500ohm. Its a speed control not a volume pot in function and there is also the question of linear or logarithmic curve, which may or may not effect the ease of adjustment/speed matching.

[nthall]

All of the Pioneer tables I've seen either use 10k or 20k pots. The European models must be different. I've always replaced them with spares from other tables.

I'm not sure if they are linear or logarithmic, and don't know that it would even matter which type you used.

I'd say measure the one you have and get both types. You can always use them for something else later.

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[karma67]

its a japanese model nathan,the problem has been traced,it appears to be one of the hall motor pick ups wasn't working,i collect the tt next week :)

[nthall]

Cool.

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