HK 250 power amp tube amp schematic

[eddog]

shows avalue of a capacitor to be 20K. Is the K the tolerance (10%)percentage or does it mean 20,000(pico farads or uuf). It is used to couple the ac signal from the first half of a 6cg7 tube to the driver stage. 20 pico or 20,000 pico?

Thanks for any help provided!
Mark

 

[Tube_Dude]

shows avalue of a capacitor to be 20K.

Hi eddog

The value of the cap is 20 nF ( 0,02uF ).

Cheers

 

[eddog]

Thanks tube dude, very much appreciated!
The negative feedback cap is shown as 100, so if I have this right that value is 100 pf or also known as .1 nf or less comonly today known as 100 uuf.

 

[Tube_Dude]

The negative feedback cap is shown as 100, so if I have this right that value is 100 pf or also known as .1 nf or less comonly today known as 100 uuf.

Yep! 😎

 

[eddog]

Thanks again Tube Dude😀

 

[rickl]

eddog,
Not sure where in Minnesota you live but if you are in the western part of the twin cities, I have some very nice 20nF caps you can have. I bought a bag of 'em and have plenty to share.

rick

 

[eddog]

Thanks for the offer Rick, I live south of Luverne,MN right near the dreaded Iowa border

This is my first HI-FI tube amp project for what it's worth. I repaired a friends 63' Silvertone guitar amp and have become fascinated by tubes and tube amp theory.
When shopping for coupling caps in the future, what should I look for to indicate a quality capacitor. Also can ceramic caps be replaced by other types of the same values?