Bottlehead Forum

General Category => General Discussion => Topic started by: vetmed on November 28, 2013, 06:49:42 AM

Title: Grid stoppers
Post by: vetmed on November 28, 2013, 06:49:42 AM

Carbon composition is usually the preferred flavor, can anyone say why? Thanks


Robert Lees

Title: Re: Grid stoppers
Post by: Paul Birkeland on November 28, 2013, 06:56:23 AM

It's not required, but carbon composition resistors are very low inductance, and will behave like a resistor out to very high frequencies. 

Here (http://rfdesign.com/mag/511RFDF3.pdf) is some reading on the topic.

FWIW, we have gotten good results out of using physically small 220 Ohm carbon film resistors in these positions. 

Title: Re: Grid stoppers
Post by: vetmed on November 28, 2013, 07:29:09 AM

Thanks for that. Unfortunately the link doesn't seem to work, at least for me :(


Robert Lees

Title: Re: Grid stoppers
Post by: ffivaz on November 28, 2013, 08:21:21 AM

Add an "f" for pdf at the end of PB's link :)

Title: Re: Grid stoppers
Post by: Paul Birkeland on November 28, 2013, 08:41:08 AM

Fixed.