Ampdog
R.I.P. 23 June 2022
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.)
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.)
