Broken Motor Control on Beseler 16 Paper Processor

The small college I am attending uses a donated Beseler 16 paper processor for color printing. We have no manual for the thing.

The rollers seemed to be running very fast and we noticed that the control knob on front was not changing the speed. So we pulled the front panel off and here I have some questions.

1) I am attempting to get a copy of the manual. Anyone have experience with KHB in Canada?

2) The knob in question is connected to what appears to be a 10K linear potentiometer which has been stripped because of wear. Can anyone confirm that this is indeed just a standard 10K pot that can swapped out with a new one purchased from an electronics supply company?

I appreciate any help I can get.
Thanks,
Cynthia

1) I've bought a couple manuals from KHB, If they have it they'll usually ship within a day or two, after that it's up to the post office.

2) You should be able to find a replacement pot without too much trouble at a well stocked shop. If you can, take the old one along (after carefully noting the connections). There are some variations on the taper of the pot and it may be CW or CCW.

Best of luck.

George

Hello Cynthia and welcome to APUG. Have you tried contacting Beseler? Or email them? Maybe they have a schematic for it, which would have the info. Good Luck.

The potentiometer might want to be replaced with a multi turn potentiometer. Rarely do you want to change it, so perhaps get it running, and leave the control behind the front panel. Blank of the knob.

If the thing is being used for RA-4, get the kodak Z manual for the process. I highly recommend Kodak's RA-RT - a chem line designed for roller transports, and resistant to the more aerial oxidation that they give to the chemistry compared to deep tank processors.

If the tanks are running at 38C (this can be tested by running water in all tanks, and letting the temperature stabilize for a while) then you are aiming at 45' in the develioper, and 45' in the bleach fix.

The other thing that goes in older electroncs of the vintage we are tlking about here are the electrolytic capacitors. Replacing them is usually a stright forward fix for anyone familiar with repairing electronics.

KHB - Kevin Brown and his crew can repair or modify almost anything photographic.

Thanks for all the input.

I have ordered the manual from KHB and they are sending it, so that should be coming sometime soon.

My buddy is trying to contact Beseler for suggestions.

Right now the processor is running too fast. If we can fiddle with it to get the right speed, blanking out the knob may be a good way to go.

What I would like to do is replace it with a new pot. Right now, though, we students need it working for our assignments, so we'll be somewhat conservative with the fix.

My buddy and I are also looking to get a Colenta Colette processor up and running. We've been told the dryer on it is running way too hot and is burning paper. Our first attempted fix may be to disconnect the dryer.

Cynthia

My drier on my fujimoto cp-31 went wonky, and ran too hot when it was told to be turned on by the processor. I took the control board out, swapped all of the electrolytic capacitors. One was non-polarised - likely the hysterisis module - make sure to note if yours has any that way.

The other thing might be a bad thermistor, that tells the controller when the heater is hot enough, and when to shut off.

Re capacitors...
Mike is right. Electrolytics in any equipment more than ten years old are suspect. If a failure can be caused by a bad cap, it usually is.

Re pots...
The speed control pot should definitely be linear.
Logarithmic and other tapers are used in audio circuits and analog computers. There are 12 different standard tapers (if you include linear).

- Leigh