Scary about the regulator.... I was thinking about how those ss octal replacements I linked are.......I guess not cool looking though compared to the gas...........
What do you mean by it wants 250v unloaded??? B+ should be 250??
Also, The original 1954 circuit is a bit vague on the metering and I haven't grasped how it is supposed to be done...
Do you have a drawing of yours yet???
Did you implement the one balancing circuit using the 6.3vac as well???
Excited for your progress...... I thought the original poster of this thread loved the circuit but I came across a thread in the black market , posted some time after, where he actually ended up selling it because he couldn't get it to work?
So I'm confused if anyone ever actually tried it......
Well, I turned off the regulator before actual damage was done, but the glue had turned to liquid for sure atop the foam. The weird thing is that it wasn't drawing anywhere near maximum current according to the datasheet. It was at about 33 ma. So it's probably just a matter of aging parts. I should probably send a message to the ebay dealer if emrr is right and get my money back.
The only drawing I have I did with pen on a piece of computer paper and it's really just for me to understand... a lot of the PS values have changed, etc. I just put a 1 ma meter beyond the 22 kohm resistor to ground and put a 100Ω pot across it. It definitely functions correctly, but really doesn't dip enough for my liking. I have a switch for it in case it causes distortion. Also made a switch for the second time constant, and of course, created adjustable attack and release on the first one. Weird part is that adjusting the attack should also affect the release. Not a problem for me though.
I used DC heaters like I said from a seperate filament transformer. I hit a bridge rectifier, 45000 uf with .33 in between 15000 and 30000... got about 19mv of ripple. Thing sucks in about 3.2 amps of AC from the transformer, which is well below rating. So in order to implement the balance circuit, I took the 6.3 ac line off of the power transformer itself, let it hit a pilot light on the front panel (which has since burned out as it was likely about 80 years old) and let that hit the balance circuit.
I'm unsure cannikin ever got his working. I wouldn't be surprised if he did not considering that he didn't post audio. But maybe he did and we can no longer see it here.
It should work with 250V B+ measured at the node when connected, that is what the drawing means. Layout could cause motor boating, making the coupling caps too big could cause it, you can always throw more filter capacitance at those two points and see if it clears it up at the higher voltage. How far down is B+ for it to work?
1mA idle is totally believable given the resistances.
Look at the BA-6A metering, which is the type PRR referred to back on page one. Same as many other limiters. Look at SA-39. Notice all the resistances here are scaled way up from the BA-6A, so current will be lower, will need a more sensitive meter.
B+ is about 196V now at that node. Regulator tube is warm, but drawing only 23 ma. I have definitely not overloaded on filtering (choke-20-30-30). This project was a lot of using crap I already had (aside from the interstage) so I didn't want to create too much sag cause I was using a 5Y3.
However, I discovered a grounding problem in the sidechain. Fixed it, might go back to the way it was for some more tests. Still, shouldn't result in the regulator smelling like that. That's what I get for picking the rugged one instead of the bare tube, I guess.
And yeah, you're right. I'm not positive what kind of meter I'm going to need if I want to see a proper resolution. Will have to do some tests with a rather beefy signal.