Yamaha CA-1000 Front Panel Potentiometers replacements?

[Yamaha5000]

I am looking for information on possible substitutes for the Bass, Treble, Loudness potentiometers.
The Bass & Treble appear to be logarithmic with a center detent. Correct? They are also Dual Shaft which is a lost Art, with no possible new replacements. Correct?
The Loudness appears to be a Taper with 10 detents. Correct?
Possible complete new part numbers?

Should these pots be taken apart for cleaning are internal parts available?

Loudness Pot: When measuring with a DMM it appears to have a slow progression from 0ohms and then after 50% of rotation the value changes are much greater. So what would be the technical description of that action?

 

[mbz]

The Bass & Treble appear to be logarithmic with a center detent. Correct?

Each 10 positions are detent, at least on the units I've worked on

hey are also Dual Shaft which is a lost Art, with no possible new replacements. Correct?

Yep, dual shaft

The Loudness appears to be a Taper with 10 detents. Correct?

On the road, can't confirm, from memory no detent???

Loudness Pot: When measuring with a DMM it appears to have a slow progression from 0ohms and then after 50% of rotation the value changes are much greater. So what would be the technical description of that action?

Refer to the taper shown in parts list, A=Audio=log, B=linear taper.
Bass/trebble and loudness appear linear

Are your items confirmed faulty, a parts unit is the obvious replacement plan or is this an OCD thing where you must have new parts. I can send you items from parts unit but I'd think they'd be readily available in the US. Many models similiar, ie, CA-800,,,, CR-....

 

[Yamaha5000]

I really don't know what I would gain from pots out of a parts unit, that would be passing dirt from one unit to another.

The only way that I can see to reuse pots is to do like the guy in Poland who uses a lathe to disassemble the pots, clean, lubricate and then reassemble. I guess the Carbon deposits don't wear or degrade over time? it is just the dirt and grime issues?

With the slide switches it is rather simple to take apart, clean, lube and reassemble. Works just like new.

I didn't understand the parts list designation of "A" & "B"
What does HB stand for?



What does 8Z and 9Z stand for?






They are also Dual Shaft which is a lost Art, with no possible new replacements?

Refer to the taper shown in parts list, A=Audio=log, B=linear taper.
Bass/Treble and Loudness appear linear
Loudness Pot: When measuring with a DMM it appears to have a slow progression from 0ohms and then after 50% of rotation the value changes are much greater. So what would be the technical description of that action?

Possible complete new part numbers?

 

[Yamaha5000]

I can send you items from parts unit but I'd think they'd be readily available in the US. Many models similiar, ie, CA-800,,,, CR-....

At the very best maybe you can purchase a CA-800 beat to near death for $225.00 including tax and shipping.
ALPS RK-27 pots can be purchased for $20.00 each, so that is 12 new pots. Just wish I could determine the complete part number for the ALPS.
And the CA-800 is not the Dual Shaft like the CA-1000.

 

[Yamaha5000]

Appears to be a quality product? Now to locate a parts supplier that can provide?

 

[Yamaha5000]

What does 8Z and 9Z stand for?

What does 8Z and 9Z stand for?

 

[Yamaha5000]

A or B or ? Curve?
HS12034
CURVE OF POT ACTUAL MEASUREMENTS
RESISTANCE IS VERTICAL, DETENTS ARE HORIZONTAL

 

[Yamaha5000]

10K HS12033
A or B or ? Curve?

CURVE OF POT ACTUAL MEASUREMENTS
RESISTANCE IS VERTICAL 0-10K
DETENTS ARE HORIZONTAL 1-10 DETENTS

 

[Yamaha5000]

Is there such a pot that is Log (Audio) and Inverse Log? The values I have measured seem to show these characteristics or has decay of the Carbon resulted in these plots?

 

[Yamaha5000]

Example on 10K pot, sure appears to be a lack in precision?

1st pot on shaft:
.35
148
475
754
2500
5000
8000
9000
9268
9609
9700

2nd pot on shaft
.27
177
535
777
2630
5000
7600
8250
8580
8880
8940

 

[Yamaha5000]

Loudness Pot 20K