speed potentiometer id

What people are working on at the moment
jayman67
User
Posts: 90
Joined: Sat Jan 07, 2017 10:00 pm

#1 speed potentiometer id

Post by jayman67 »

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?

Image
User avatar
rowuk
Old Hand
Posts: 453
Joined: Sun Jun 01, 2014 2:50 pm
Location: Germany

#2 Re: speed potentiometer id

Post by rowuk »

I am pretty sure that you can't just replace the pot without further adjustment. Here is a website with manuals and schematics. This should get you much closer!

http://www.hifi-manuals.com/Pioneer
Whenever I feel blue, I start breathing again.
jayman67
User
Posts: 90
Joined: Sat Jan 07, 2017 10:00 pm

#3 Re: speed potentiometer id

Post by jayman67 »

unfortunately my tt is not in there,this one looks like it should work ok
http://www.mouser.co.uk/Search/ProductD ... E425K504A2
i hope lol
User avatar
jack
Thermionic Monk Status
Posts: 5493
Joined: Wed Dec 29, 2010 8:58 pm
Location: ɐılɐɹʇsnɐ oʇ ƃuıʌoɯ ƃuıɹǝpısuoɔ
Contact:

#4 Re: speed potentiometer id

Post by jack »

karma67 wrote: Sun Feb 12, 2017 12:18 pm unfortunately my tt is not in there,this one looks like it should work ok
http://www.mouser.co.uk/Search/ProductD ... E425K504A2
i hope lol
The implication from the data in the original post is that this is a 500 ohm resistor.

The Bournes part you linked to is 500K ohms, i.e. 1,000 times larger...
Vivitur ingenio, caetera mortis erunt
jayman67
User
Posts: 90
Joined: Sat Jan 07, 2017 10:00 pm

#5 Re: speed potentiometer id

Post by jayman67 »

cheers,yes i realized id made a mistake,the search continues :)
User avatar
DSJR
User
Posts: 193
Joined: Mon Jan 11, 2010 11:11 am
Location: Suffolk Coastal

#6 Re: speed potentiometer id

Post by DSJR »

Does the speed wildly fluctuate if you so much as breathe on the speed pots? is there an obvious sweet spot with all manner of things happening either side of this? If not leave well alone and settle for the fact you've properly cleaned them as I doubt they're worn. Can you solder to an indistinguishable standard from the factory as proper service techs can, or is it going to be an obvious repair/bodge further down the line?

Sorry to ask the above questions, but please don't butcher an otherwise classic turntable just 'cos some peeps on an internet audio forum 'told you' to, as it really may not be necessary and Noble was a very good form making things like this I assure you.
User avatar
cressy
Shed dweller
Posts: 2906
Joined: Fri Aug 03, 2007 7:07 pm
Location: the great white space
Contact:

#7 Re: speed potentiometer id

Post by cressy »

You will also need to know wether the pot is a lin or log taper if you do change it.
If you do have speed issues I would be looking for old leaky caps first, carbon track pots are pretty reliable, when I have refurbed old dd decks i have found a clean is usually sufficient for the pots
jayman67
User
Posts: 90
Joined: Sat Jan 07, 2017 10:00 pm

#8 Re: speed potentiometer id

Post by jayman67 »

dont worry,unless i can find the excact matching pots im not replacing them,oh and dave no one is bodging or butchering anything mate ok!
SteveH
User
Posts: 68
Joined: Sun Feb 12, 2017 4:46 am
Location: Whangarei,in my mess.

#9 Re: speed potentiometer id

Post by SteveH »

It's a linear(B) pot.
jayman67
User
Posts: 90
Joined: Sat Jan 07, 2017 10:00 pm

#10 Re: speed potentiometer id

Post by jayman67 »

thanks steve,the hard bit is finding 500 ohms with a 26 mm spindle.
User avatar
Mike H
Amstrad Tower of Power
Posts: 20157
Joined: Sat Oct 04, 2008 5:38 pm
Location: The Fens
Contact:

#11 Re: speed potentiometer id

Post by Mike H »

 
"No matter how fast light travels it finds that the darkness has always got there first, and is waiting for it."
jayman67
User
Posts: 90
Joined: Sat Jan 07, 2017 10:00 pm

#12 Re: speed potentiometer id

Post by jayman67 »

yep i can find ones close,what would the effect be of using one with a different resistance please?
User avatar
cressy
Shed dweller
Posts: 2906
Joined: Fri Aug 03, 2007 7:07 pm
Location: the great white space
Contact:

#13 Re: speed potentiometer id

Post by cressy »

I wouldnt have though the 30r would make too much difference, it will limit the adjustment range abit if it is as simple as the pot in series with the board and motor, it depends on the way the adjustment is actually done
User avatar
Mike H
Amstrad Tower of Power
Posts: 20157
Joined: Sat Oct 04, 2008 5:38 pm
Location: The Fens
Contact:

#14 Re: speed potentiometer id

Post by Mike H »

No way are you going to find a 500R one, that's one of the olde worlde values. '5' became '4.7', '50', '47', etc.
 
"No matter how fast light travels it finds that the darkness has always got there first, and is waiting for it."
SteveH
User
Posts: 68
Joined: Sun Feb 12, 2017 4:46 am
Location: Whangarei,in my mess.

#15 Re: speed potentiometer id

Post by SteveH »

470R is within 10% of the original so it shouldn't cause any problems. There may also be a preset trimpot somewhere which sets the adjustment range of the speed pot.
Post Reply