Save the Old Oscilloscope!! (div switch malfunction)

[Patent.STM]

Dear all,

I have an old oscilloscope with a bad div knob, the symptom is the input signal gone when the knob is set to .1 or  2 div.

the div knob looks like the attachment (referenced image from from google cache). confirmed some damaged contacts, not a cleaning problem.

the old scope is working great but the knobs become a real problem.

is it possible to order a new switch?
is it possible to build up a relay-array and replace the old switch?

I like this old scope very much, it's been very precise even 15 years after production.
Please let me know if anyone has an idea of saving this oscilloscope.

(Picture updated, it's the most similar one on google cache but the korea page is no longer available)

[robrenz]

We need some close up clear pics of the real thing to be able to help. Especially the possibly bad contacts themselves. I would think that some careful reforming of the switch contacts to re-establish contact pressure and some Deoxit would at least give some signal thru.

[DmitryL]

.. once upon a time I decided to clean similar noisy wafer switches on my old Hitachi scope with a contact cleaner spray... The board was covered with a thick layer of rosin flux, and the spray dissolved the rosin and sneaked into the wafers by capillary effect. I had to desolder these switchesand wash them in IPA in the ultrasound bath..
So, be careful

[Alex Eisenhut]

Check the solder joints under each wafer.

[Patent.STM]

hi everyone,

I have tried to find out the most similar switch.
It is pretty confirmed that the switch has some missing parts, therefore the switch itself is  un-repairable.

please let me know if there is someway to order a new one, or there is any relay-like switches suitalbe for such usage. thank you so much!!

[elliott]

.. once upon a time I decided to clean similar noisy wafer switches on my old Hitachi scope with a contact cleaner spray... The board was covered with a thick layer of rosin flux, and the spray dissolved the rosin and sneaked into the wafers by capillary effect. I had to desolder these switchesand wash them in IPA in the ultrasound bath..
So, be careful

Hitachis are apparently bad about that, my V-1150 is still pretty dicky after hosing them with 2 cans of cleaner. I think I might have to go for the ultrasonic bath, but I do not look forward to trying to remove them.

[Patent.STM]

i were told that rosin is a thin protection on solder points, if you remove them, the solder would degrade faster than normal.