I found a PT 360 Vac in my archives, it doesn't have 5v but it's not a big deal.
So, do we resurrect it as is or do we apply modifications to it?
already, the counter-reaction to give it a little more stability.
Does anyone have another idea or should we continue like this?
So, do we resurrect it as is or do we apply modifications to it?
already, the counter-reaction to give it a little more stability.
Does anyone have another idea or should we continue like this?
Are your speakers 8 ohms?I can already confirm that the feedback resistor is indeed 1k.
there is only a 6 ohm winding on the secondary, no 4 or 8 ohm.
In general, I find the 4K opt not a good match for the 2E22 as a pentode, I guess that's the reason for the amount of NFB.
I did some simulations with 7.6K and 6.6K and the figures improve a lot.
Output power is quite low for the tube because of the low plate current at 0V g1. Interesting that the 2E22 datasheet shows curves for positive suppressor grid, could be a venue to investigate when you get things running. Also AB2, the tube can handle quite a bit of g1 current.
Do you have details about the ouptut transformer, like dcr, max dc current etc? Maybe a KT88 based rebuild, but you probably need a bigger PT.
What kind of output power would you be happy with? You mentioned that you liked the sound when it was working, so maybe that's the answer. Unless you want to experiment a bit, then the sky is the limit 😉
What kind of output power would you be happy with? You mentioned that you liked the sound when it was working, so maybe that's the answer. Unless you want to experiment a bit, then the sky is the limit 😉
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