Cleaning PL 4000 switches

[marcok]

Any ideas how to deox PL 4000 switches ?
The problem is that these switches (Alps ) are sealed
Any tips ?
Anyway last week I have just bought an old front panel board ,
that it will be here next week ,so suggestons for "strange" experiments are welcome ,
since I will have the spares .
Thank you in advance .
Marco

 

[62vauxhall]

If there is even a hint of a gap or opening, I've used insulin syringes to inject DeOxit fluid inside switches. Sprayed a little into a plastic pill cup (or whatever) and drew it into the syringe. Less wastage than spraying.

 

[marcok]

Excellent idea !
I think you insert the needle into the slot of the front panel
without disassemblying it . Have I understood well ?
Probably it's possible to use one the holes in front of the switches ,
but it' s necessary to remove the front panel to reach them .
I will investigate when I'll receive the front panel board .
Thank you and ciao
Marco

 

[laatsch55]

D100 comes in a small 2 oz bottle with a small applicator tube, works every time....

 

[marcok]

I have tested with a syringe #23 (needle 0,6 x30 mm ) after spraying the deox direct into the syringe .
After 3 days the issue occurs again .So in my opinion spraying into the slot of front panel is not the
right solution .Next week , with my hifi guru , I will test an other position where to introduce the needle :
the idea is to use the small slots located on the angle of the rear part of the switch .
Here the problem is the age and nothing else .
Thank you Lee for the suggestion . I will buy that deox soon .
Ciao
Marco

 

[laatsch55]

Marco, sometimes repeated application of de-oxit is necessary. I've had to do it up to three times...

 

[marcok]

Yes Lee ,
I know very well this matter .
but this time I would like a " definitive " therapy .( I hope )
Moreless every 3 days I go to meet my parents and every time :
no left channel , no right channel ....
It' good preamp but the maintenance is very hard .
Fortunately I have found some used spares switches in US ,
I 'm sure to fix these issues . ( when I don't know ) and
infact I have asked my hifi guru for help .
Ciao and thank you
Marco

 

[laatsch55]

Yep, I'm fighting a 3300 with the same problem, but it manifests as noise in the phono section...

 

[marcok]

Lee,
Probably the issue is not switches , because my problem is typical in Alps switches mounted in PL 4000 series 1
and 3300 is only series 2 .
I have seen the same problem but the guilty was the SME iii cable .
Ciao
Marco

 

[laatsch55]

Haven't even put it to a turntable yet, all through the AP right now...

 

[marcok]

Finally today I and my hifi guru we have fixed the issues concerning
PL 4000 switches .
After disassembling the front panel we cleaned
all the switches with CRC 2-26 , but the problem always
occurred random when you moved some switches .
Anyway after 3 hours my hi fi guru realized
that there were many bad contacts between mother board
and front panel board , " amplified " by the operiations of the
switches .
Solution : clean and resolder the male connector on the front panel board .
Now everything looks O.K.
Probably these bad contacts are due the flexion of the front panel board .
Ciao
Marco