Cap "C8" on QUAD 405.2 PCB

[ClassA]

Cap "C8" on QUAD 405.2 PCB

Hi,
I want to replace the original C8 (ceramic cap) with a new cap for QUAD 405.2 but I do not know the spec of the original C8 (120pF/?V). Is there anyone know about it? I have some philips n12 cap (film cap?) with black or purple color on the top of the caps. Can I use them to replace C8? What is the meaning of the color? Which color should I use? Is it better to use silver mica cap (120pF/100V) to replace C8?

Thanks!

 

[RogerGustavsson]

My 405-2 has a 120 pF at the C8 position. I do not know the type of it. I will have a look this evening.

 

[RogerGustavsson]

I have just been taking a look inside my Quad 405-2. C8 is a 120 pF ceramic disc capacitor, lead spacing is 7.5 mm. The PCB in my Quad 405-2 is 12565 Issue 5.

 

[ClassA]

Hi Roger,
The C8 on my 405.2 is a ceramic disc cap with purple color on the top and marked 121J (should be 120pF) but I do not know its voltage spec.

 

[RogerGustavsson]

I would use a close tolerance polypropylene or polystyrene capacitor in that position. Here is an interesting homepage:

www.dc-daylight.ltd.uk/Valve-Audio-Interest/QUAD/QUAD-405-Modification/QUAD-405-Mods.html