B+ from voltage multiplier
- Thread starter kambo
- Start date
Help Support GroupDIY Audio Forum:
You could use a dc to dc switching PS but that might break the OM....
JR
JR
Winston OBoogie
Well-known member
If it's a beefy heater transformer that you have, then it'd be OK to use another small heater transformer in reverse from that existing heater transformer's 9 -12v. This is assuming this extra transformer can have its, what was, primary strapped for EU 240v AC.
Matador
Well-known member
This method is tried and true. Take a look at the Gyraf G9 power supply: it uses both methods.kambo said:
Winston OBoogie
Well-known member
kambo said:
Far from it my friend. Unadulterated plagiarism
As Matador posted, Jacob has a tried and trusted scheme which you could follow. or use as inspiration.
Just keep a running total of your Volt-Amps to make sure your first transformer can handle everything.
Aren't power transformers like toroids used in small signal qiute cheap this days? Here in eastern Europe it makes more sense ordering custom one than buying two EIs, most companies also export to Germany... I'm used to ordering 2x max power for lowest EMI for HT, even several heater taps and +-15V for signal level solids state with all shields comes cheap.
Let's say toroid with 230V/50mA, 7 and ~7,5V@1,5A, 45V/50mA and +-15V at low I (low signal levels) with electrostatic shields and stuff. How much would it cost where you guys live? It really interests me because V doubler questions surfaces so often.
Let's say toroid with 230V/50mA, 7 and ~7,5V@1,5A, 45V/50mA and +-15V at low I (low signal levels) with electrostatic shields and stuff. How much would it cost where you guys live? It really interests me because V doubler questions surfaces so often.
Matador
Well-known member
Do you know how much current you need from the B+ supply? That will dictate possible solutions more than anything else.
pass....kambo said:
JR
Matador
Well-known member
Those charge pump designs aren't good outside of a handful of mA's, and with the high edge rates are noisy too.
I would stick with the G9 methods, as there are three there to try: a traditional IC regulator (TL783), a voltage multiplier, and even a discrete regulator.
I would stick with the G9 methods, as there are three there to try: a traditional IC regulator (TL783), a voltage multiplier, and even a discrete regulator.
Winston OBoogie
Well-known member
Matador said:
+ 1
+1 from me too..Winston O'Boogie said:
because i haven seen anything more practical than this... using it all the time!
i sometimes use those chepo yellow trx on both side, if only need some tiny current for s single tube sitar fx psu!
ruffrecords
Well-known member
Transformers for tube work are available e.g:
http://www.ampmaker.com/store/240V-6.3V-toroid-power-transformer.html
Cheers
Ian
http://www.ampmaker.com/store/240V-6.3V-toroid-power-transformer.html
Cheers
Ian
Winston OBoogie
Well-known member
Hey that's a decent price for that!ruffrecords said:
One thing, I do wish heater windings were a tad higher voltage for DC in general. I know AC mains tends not to drop too much on the whole, but once you allow for a 10% low line and even using Schottky diodes, it only gives some 1.5 volts for a CRC filter and across a regulator. Even running heaters at 6V rather than 6.3 and using a low drop out regulator chip, I never feel 100% comfortable the reg won't drop out of regulation when out in the World.
I suppose if it were 7 volts, then the AC guys wouldn't be too happy
so I understand.Otherwise
