SCC88/PCC88 heaters in series?

AVForums

Help Support AVForums:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.

Ampdog

R.I.P. 23 June 2022
Joined
Aug 27, 2006
Messages
7,611
Reaction score
455
Location
Pretoria, South Africa
I posted this problem years ago and cannot now locate the thread.

I had the inconvenient experience to discover that there is an unacceptable current variation in heaters of certain ECC88 valves. Trying to operate heaters in series I found  from 5,7 - 6,9V drop across certain heaters. This would indicate an inconsistency heater wire gauge/length!

I have not experimented with PCC88s (which would be more convenient for me) but am loathe to spend the money only to find the same inconsistency there.

Has anybody experienced this?  (It also avoids that one could use a handy string of ECC88 heaters  in series for convenience of d.c.feed.)

(I could not find specific reference to this on internet.)
 
Top