RA870BX - best way to clean this switch?

[tfaust]

I have intermittent issues with distortion and low volume and tapping the monitor switch seems to help for a bit. Tapping the sliding part not the rotary part. Rotel has the part number as 064c-4175A52 but it’s obviously an Alps switch, likely custom ordered. I don’t know if cleaning it would help or if it’s worn out. I am also wondering why they left pins unsoldered,you’d think they would have if for no other reason than mechanical support. Any insights into how to handle this? Thanks

 

[DatunWalnut]

I have just serviced a Marantz Pm66se ki signature. It has the same switch. The top bit attached to the cable (for want of a better word) that goes to the knob clips off leaving the silver block connected to the PCB. You then have to desolder that and dismantle it. The contacts can be cleaned with silver dip on a cotton bud. It all depends on how familiar you are with opening switches. If you've done it before or are happy to take the plunge, great. If not just try to squirt some D5 or D100 in and hope for the best.

 

[tfaust]

Thanks, I was wondering if the plastic piece just clips on and off or if removing it would break it.

 

[PF Sound]

I believe if you unsolder it from the board you can bend the little tabs (looks like 5 on each side) holding the top to the pinned portion & it will come apart. Go slow when you get to separating. It can be a pain but many times it's the only way to truly get them clean.

 

[avionic]

I believe if you unsolder it from the board you can bend the little tabs (looks like 5 on each side) holding the top to the pinned portion & it will come apart. Go slow when you get to separating. It can be a pain but many times it's the only way to truly get them clean.

One step better. Ultrasonically clean the sliders and contacts while you have disassembled.

 

[rickl]

I'm fighting a similar switch in a NHT sub amp. going to take it apart tomorrow.

I bypassed it and the amp works.

 

[DatunWalnut]

Handy hint if you haven't got an ultrasonic cleaner: Use silver dip jewellery cleaner on a q-tip. That removes all the silver sulphide and brings the contacts up like new without abrasion.