02-02-2021, 06:28 PM
Hi Peter.
No need to apologise.
I've been repairing amps with the 300B triodes.
They feed AC to the filaments with separate supplies for each valve, four on a stereo push pull amp. Each have hum bucking pot, they are a nightmare to set up and really can only be done on a scope. Unfortunately they drift which is no good for the customer.
Another had DC feeds to the filaments but its a horrible design. This of course is to satisfy the audio fools.
I've made up a reasonable amp for a battery radio with the 1j29b, it's around 200mw and with an efficient speaker and baffle it's plenty loud enough.
Good luck with your PP amp, I'm genuinely interested in the end results.
No need to apologise.
I've been repairing amps with the 300B triodes.
They feed AC to the filaments with separate supplies for each valve, four on a stereo push pull amp. Each have hum bucking pot, they are a nightmare to set up and really can only be done on a scope. Unfortunately they drift which is no good for the customer.
Another had DC feeds to the filaments but its a horrible design. This of course is to satisfy the audio fools.
I've made up a reasonable amp for a battery radio with the 1j29b, it's around 200mw and with an efficient speaker and baffle it's plenty loud enough.
Good luck with your PP amp, I'm genuinely interested in the end results.
