advertisement


Cleaning dirty pot?

Servisol Super 10 switch contact cleaner. Spray into both sections of the pot, waggle back and forward over its full travel half a dozen or so times and leave for ten minutes to dry off.

If that doesnt fix it, then I'm afraid you need a new pot.
 
Beobloke said:
Servisol Super 10 switch contact cleaner. Spray into both sections of the pot, waggle back and forward over its full travel half a dozen or so times and leave for ten minutes to dry off.

If that doesnt fix it, then I'm afraid you need a new pot.
Click to expand...
Thanks for the tips. A new pot is unlikely to happen. Where (the heck) would I find a "non twinned" dual pot?

BugBear
 
bugbear said:
I have a Marconi TF2700, 1960s technology.

https://www.pinkfishmedia.net/forum...00-universal-bridge-how-to-get-spares.215205/

It all seems to work. Nearly. One control is very twitchy in its operation, only working at some settings.

It's a dual axis pot, 2.5K Linear and 25K Log. Hard and/or expensive to replace.

It's physically quite big. Any standard tips on improving/cleaning it?

BugBear
Click to expand...
bugbear said:
Thanks for the tips. A new pot is unlikely to happen. Where (the heck) would I find a "non twinned" dual pot?

BugBear
Click to expand...

They are also 1W and 2W power rating and possibly "semi precision" so no there is virtually zero chance of replacing them.
 
OK, here's a thought - how about making something out of a stepped attenuator. How much precision would you need between steps to get the bridge to function adequately?

Failing that a visit to the next nearest Ham radio rally would probably yield another one waiting to be refurbished or scavenged.
 
MJS said:
OK, here's a thought - how about making something out of a stepped attenuator. How much precision would you need between steps to get the bridge to function adequately?

Failing that a visit to the next nearest Ham radio rally would probably yield another one waiting to be refurbished or scavenged.
Click to expand...

If they are part of the bridge balancing (likely) they need to be infinitely variable as we are looking for a sharp null.
 
I thought that might be the case, I've never used one though. Was just thinking out loud as to whether it would gain any useful functionality instead of an infinitely variable but noisy pot.
 
Beobloke said:
Servisol Super 10 switch contact cleaner. Spray into both sections of the pot, waggle back and forward over its full travel half a dozen or so times and leave for ten minutes to dry off.

If that doesnt fix it, then I'm afraid you need a new pot.
Click to expand...

Yep, that's good stuff.
For the icing on the cake, once the Super 10 has evaporated, follow through with a quick burst of Caig Faderlube.
 
I don't know what Caig Superlube is but a good plastic lubricant, as used in CD mechanisms etc, normally gives 100% cure. i think the one I use is caled 'SPL' or Special Plastic Lubricant
 
I find several small applications over 3 days/and operation and finally a touch of gold dioxit never fails
 
It is expensive, but Deoxit Faderlube really is The Stuff and really can save vintage amps, guitars etc without having to replace the original pots. The can will last most people for a good decade or more so well worth having one knocking about as it cleans pots and they stay clean too as it lubricates them with the de-oxidising stuff. The non-lube switch cleaner D7 is very useful too. I have the full set here with the Gold F5 too, but that is being quite obsessive and to be honest it is the least useful of the three as gold contacts stay clean anyway!
 
This site contains affiliate links for which pink fish media may be compensated.
agreed I have a shelf full of them , last for ever .theres no doubt that in most caseS pots can be saved . quad switches respond very well. tape recorders rubbers can be sorted with print roller cleaner PLATENCLENE
 
You must log in or register to reply here.


advertisement


Back
Top