Home |
Search |
Today's Posts |
#1
|
|||
|
|||
1600 volt 250 ma Constant Current PS
This one was built in the 60's. It has both +ve & -ve rails for the error amp. Stability depends on the 85A2 gas regulator & the current sampling resister. Not sure but it is probably a 50W Dale, Hi stability.
I can't remember where this was used. There are a lot of appplications for constant current supplies. You can see the primary elements of the cct are the same as a constant voltage supply. Very few changes required for the conversion. With 6X807 in pentode mode as passers there is lots of power available. The whole thing covers several pages so doesn't fit well here on Audio Banter. And my hand drawn schema are fading with age. Perhaps Patrick T could give us his take on it! Cheers to all, John |
#2
Posted to rec.audio.tubes
|
|||
|
|||
1600 volt 250 ma Constant Current PS
On Tuesday, 22 January 2013 09:50:51 UTC+11, John L Stewart wrote:
This one was built in the 60's. It has both +ve & -ve rails for the error amp. Stability depends on the 85A2 gas regulator & the current sampling resister. Not sure but it is probably a 50W Dale, Hi stability. I can't remember where this was used. There are a lot of appplications for constant current supplies. You can see the primary elements of the cct are the same as a constant voltage supply. Very few changes required for the conversion. With 6X807 in pentode mode as passers there is lots of power available. The whole thing covers several pages so doesn't fit well here on Audio Banter. And my hand drawn schema are fading with age. Perhaps Patrick T could give us his take on it! Cheers to all, John +-------------------------------------------------------------------+ |Filename: 1600 volt 250 ma Constant Current Power Supply.jpg | |Download: http://www.audiobanter.com/attachment.php?attachmentid=333| +-------------------------------------------------------------------+ -- John L Stewart I looked at the schematic but its a constant current output, not a constant voltage, so about useless for any amplifier B+ supply, and I have not tried to decipher the way it works millisecond by millisecond. So I'll pass. I'll take the easy way out, that's "my take on it". No doubt is has apps. The trubble with gettin old in a fast changing world is that by the time a man has learnt to make a really fine wooden wagon wheel, some ******* invents a horseless lorry with rubber tyres. For thousands of years before 1800, you'd be able to pass on knowldge that would be useful. But who now wants to know the schematic for Appolo 11 space craft, apart from Chinese playin' catch up? Goin' fo' a ride termorra before the heat begins late morning. I got many more useful things to occupy my mind than on ancient old circuits for which I can't think of a use. Rebuilt oscillator THD checker last week, I can now see 0.0003% with ease, ie, far less noise. Now re-building millivolt meter from 1994 so it has 4 opamps, one input buffer, 2 gain stages of gain = 11, then one opamp with diode bridge in FB path to power a very nice old analog meter. That will allow me 1Hz to 2MHz, 0.3mV to 1,000V ac, high Z input. It will be better than previous arrangement with passive Ge diode bridge after discrete transistor amp, and only 6 ranges all 0 to 10. New ranges have 0 - 3, 0 - 10, 0 - 30, 0 - 100 etc. So low end of readings 1 - 10 can be more accurately measured. Then I have at least a year full of unfinished projects left over from my 18 years of being audio tech. How time flies, and retirement feels just great, no more deadlines, hardly a customer in sight with yet another POS to fix, and I can happily hang up the phoan on ppl I don't like the sound of. Patrick Turner |
Reply |
Thread Tools | |
Display Modes | |
|
|
Similar Threads | ||||
Thread | Forum | |||
Low Cost Constant Current Solution for Low Resistance Measurements | Vacuum Tubes | |||
Need volt/current specs for Tascam M520 mixer PS | Pro Audio | |||
Filament heating: constant voltage or constant current? | Vacuum Tubes | |||
Constant Current Source For linestage design | Vacuum Tubes | |||
Constant current source for differential amp | Vacuum Tubes |