Electronics Parts for Fisher 1265-X

[Minature_hero]

Hi Everyone.

I'm trying to repair my dad's Fisher 1265-X. I need a replacement variable resistor or potentiometer. It's the sensitivity dial with the integrated switch "push for max" detailed on the scope. Just wondering if anyone may know where I can get a spare before I try fitting a 100k pot and a separate switch.

It's marked VA388-100k and I think it's made by Clarostat or Honeywell.

Thanks for your help!

[Fusion]

It may be worth contacting FisherLabs directly:
http://www.fisherlab.com/hobby/contact.htm

[FULLTIMER]

Try RS Componants ,might be worth looking here https://uk.rs-online.com/web/c/passive- ... resistors/

[ratty]

This company are very good and they answer the phone...

https://www.bitsbox.co.uk/

[Minature_hero]

Thanks for all your replies. Checking out all the suggestions but as it's a modular potentimeter I reckon only Fisher may hold out hope. Maybe one of you hobby electronics may have one in your box of bits? I will try post a pic later.

[Fusion]

What's actually wrong with it ? The pot? The switch ? It may be repairable, if the appropriate sub-part is available.

[targets]

look on the bay site ..likely there will be 1 on there if you use the specs

[maylandmanta]

If its the type I think it is - ie the spindle you turn is also a momentary switch that you push they are difficult to get hold of.Could not see any listed on Ebay etc.Have you tried flooding it with switch/contact cleaner several times and work it to see if that helps.Have also read that if you carefully open the pot up and rub a very soft pencil over the carbon track this often cures a lot of faults but have never tried it myself.
If all else fails I would go down the route you suggested and fit a simple potentiometer and a separate momentary switch.If you do this buy a good quality switch as the cheap ones have a habit of not always making contact.


Steve

[salford44]

Maybe try ringing Pentechnics,he used to repair older Fishers,he might be able to help.

[Minature_hero]

Yeah it's the momentary push one. I tried opening the case carefully but it's not designed to be fiddled with so it's properly broken now.

How do I find contact details for Pentechnics?

[Koala]

isn't the 1265x pull for max sensitivity. Opposite to the 1266x. I jam something underneath as its far to easy to knock in.

shouldn't be momentary. The only momentary is the trigger pinpoint


personally if required I would just change for a standard PoT and run permanently at max.

[Fusion]

Here's the relevant bit of the 1265X schematic, showing how the pot and switch are joined.
It's probably easier to obtain just a pot, to original spec, and work around the switch issue.
You likely don't want it 'Max' continuously, but the ability to go closer to max is useful. I suggest replacing the switch with a permanent 1M0 ( one Megohm ) resistor. This will be a 'halfway' solution, you will have 2M0 connected to +8Volts, rather than the choice of 1M0 / open-circuit.

I did find this on 'EchoBay', UK seller:
"echobay".co.uk/itm/100k-Potentiometer-With-Pull-Switch-A3012866-5-CLAROSTAT-HONEYWELL/113944845411

Attached:

[salford44]

If you google Pentechnics he has a website,his landline is 01785 714373,hes very helpful.