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Another Volume Control Question
#1

I have yet another radio [42-PT95] which has excellent sound and is working perfectly, except for one thing. The lowest volume when the radio turns on is higher than I would like.

There is no crackling or static when the volume is increased (and it does steadily increase), but it is a mid level volume when set in the low position.

Is this a dirty contact problem in the volume control.

If so how, do I successfully clean this.

- Do I need to remove from radio first ?
- Do I need to take apart ?
- What should I use to clean it ? [be specific please with Name of product and possible link to product]
- Do I need to replace the volume control ?

Sorry for the questions about minute details, but I have messed up a few radios by using the incorrect proceedure or wrong type of cleaner etc. I would like to avoid that this time if possible.

Thanks.
#2

I think the control is open. You can confirm by disconnecting one end and measuring resistance. (Forget about the middle lug for now.) If it is open, there is virtually no hope, and you will have to replace it. But if it is still good, then further investigation is needed. Sometimes a ground or B- wire gets disconnected or whatever which can have exactly the same effect. Let us know what you find.
#3

OK stupid question, but I will ask anyway.

The on/off/volume control has 3 connectors on the top and 2 on the back face.

I am assuming you are talking about the "outside" connectors of the 3 on top.

I am assuming that the 2 connectors on the back face are for the on/off switch part.

Additionally, when you say
Quote:disconnecting one end
, I am assuming you mean disconnect the wires on one of the outside connectors, but it is ok to leave the other wires connected. Is this correct ?

As far as measing the resistance, what am I looking for, if it is bad ?
#4

You are doing fine. The two on the back of the control are the on of switch. The three on the control are for volume. Disconnect either extreme end, and measure resistance end to end, should be 100,000 to maybe 500,000 ohms, but definitely not open circuit.The "arm" or center tab should vary on the ohm meter from near zero to the limit of the control as you advance or decrease the movement. Do al this stuff definitely with power off.

If you don't have a dependable meter, there are a lot of modern inexpensive digital meters (less than $25) available everywhere.
#5

Good job for a good analog meter.
Terry




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