Power Supply

jkeny · 29th January 2007, 12:03 AM

Can anybody tell me what category PS this is? (voltage doubler?, etc). Is it reasonable - it looks very basic to me? How can I improve it while using existing trafo?

It's from a Rogers cadet III integrated amp. I am rebuilding output stage to Gingertube's baby Huey schema with Sy's LED cathode biasing idea (red light district amp).

I wanted to give a clean, robust PS to this output stage. I was thinkg of using SS soft recovery diodes (any recommendations?) but am worried about inrush current & life of tubes, etc. How can I avoid this?

I looked through Tubes threads but found nothing that gives me this info. Help appreciated.

John

jkeny · 29th January 2007, 09:07 AM

Sorry, I always seem to forget to post attachment

here it is!

Tweeker · 29th January 2007, 09:25 AM

Its a voltage doubler. Inrush can be limited by use of an NTC thermistor on the primary. Im sure whatever UF4007 type diodes you could come up with would be fine.

ray_moth · 29th January 2007, 10:19 AM

You can improve it by using a 10H choke instead of the 470R 1W smoothing resistor. Make sure the choke can handle the current. I would also increase the reservoir cap from 24uF to 220uF.

If you want to stick with the same power trafo, then you're also stuck with the voltage doubler. It should work OK though.

Tweeker · 29th January 2007, 10:33 AM

Rather expensive mod for the screen supply, would rather use regulator tubes if going to the trouble.

jkeny · 29th January 2007, 10:51 AM

Thanks guys,

So it's a voltage doubler - just didn't seem like other schema I have seen! I can now investigate voltage doublers.

I have changed the smoothing caps from 24uF to 220uF.

Would a starter choke from fluorescent tubes be suitable? (As you can see I want to do it on the cheap - so no tube regulation I'm afraid)

thermistor seems like a good idea. What about using fast soft recovery diodes?

John

Tweeker · 29th January 2007, 11:36 AM

The fluorescent choke may work, I have no idea how much current it will take before saturating though.

I meant a simple 1-2 tube shunt reg using VR tube(s), but its still more money than a resistor or scrap. Im sure whatever fast soft recovery diodes youd like would work (within their ratings.)

29th January 2007, 12:03 AM	#1
jkeny Banned Join Date: Feb 2007 Location: Dublin	Power Supply Can anybody tell me what category PS this is? (voltage doubler?, etc). Is it reasonable - it looks very basic to me? How can I improve it while using existing trafo? It's from a Rogers cadet III integrated amp. I am rebuilding output stage to Gingertube's baby Huey schema with Sy's LED cathode biasing idea (red light district amp). I wanted to give a clean, robust PS to this output stage. I was thinkg of using SS soft recovery diodes (any recommendations?) but am worried about inrush current & life of tubes, etc. How can I avoid this? I looked through Tubes threads but found nothing that gives me this info. Help appreciated. John

29th January 2007, 09:25 AM	#3
Tweeker diyAudio Member Join Date: Dec 2004 Location: Cincinnati, Ohio	Its a voltage doubler. Inrush can be limited by use of an NTC thermistor on the primary. Im sure whatever UF4007 type diodes you could come up with would be fine. __________________ Be sure your foil hat has a good low impedance ground.

29th January 2007, 10:33 AM	#5
Tweeker diyAudio Member Join Date: Dec 2004 Location: Cincinnati, Ohio	Rather expensive mod for the screen supply, would rather use regulator tubes if going to the trouble. __________________ Be sure your foil hat has a good low impedance ground.

29th January 2007, 11:36 AM	#7
Tweeker diyAudio Member Join Date: Dec 2004 Location: Cincinnati, Ohio	The fluorescent choke may work, I have no idea how much current it will take before saturating though. I meant a simple 1-2 tube shunt reg using VR tube(s), but its still more money than a resistor or scrap. Im sure whatever fast soft recovery diodes youd like would work (within their ratings.) __________________ Be sure your foil hat has a good low impedance ground.

Thread Tools	Search this Thread
Show Printable Version Email this Page	Search this Thread: Advanced Search

29th January 2007, 10:19 AM	#4
ray_moth diyAudio Moderator Emeritus Join Date: Jan 2004 Location: Jakarta	You can improve it by using a 10H choke instead of the 470R 1W smoothing resistor. Make sure the choke can handle the current. I would also increase the reservoir cap from 24uF to 220uF. If you want to stick with the same power trafo, then you're also stuck with the voltage doubler. It should work OK though.

29th January 2007, 10:51 AM	#6
jkeny Banned Join Date: Feb 2007 Location: Dublin	Thanks guys, So it's a voltage doubler - just didn't seem like other schema I have seen! I can now investigate voltage doublers. I have changed the smoothing caps from 24uF to 220uF. Would a starter choke from fluorescent tubes be suitable? (As you can see I want to do it on the cheap - so no tube regulation I'm afraid) thermistor seems like a good idea. What about using fast soft recovery diodes? John

Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
Split Voltage Switching Power Supply for Power Amp	vectorplane	Swap Meet	2	23rd April 2011 11:48 PM
LTspice tool for power amp power supply component evaluation	andy_c	Software Tools	2	23rd August 2009 05:10 PM
Can i use a computer power supply to power audio amplifiers?	destroyer X	Solid State	91	25th September 2006 04:36 AM
selling high current power supply for power amps.	ericpeters	Swap Meet	0	14th January 2005 02:21 PM
heater supply (xformer specs are 6.3V 2.5A) as supply for a power LED?	jarthel	Tubes / Valves	10	21st July 2003 01:30 PM

New To Site?	Need Help?
Register to Participate Search Privacy Statement Contact Us	Frequently Asked Questions Did you forget your password? Mark Forums Read