Question about a TF

Jamh · 17th July 2004, 05:50 AM

I have a toroidal TF with a single primary, and dual 44V secondaries. I'm not sure about its VA rating but the thing is big (6x6x3, 18cable). I was thinking about using it with Brian's boards. Any suggestions as to the best way?

One way might be to use 2 of the power boards in series per secondary. That would give me 22V. Another would be to bleed some of the current to ground via a resistor, but I'd be worried about picking humm.

pinkmouse · 17th July 2004, 10:54 AM

That's way to high for a GC, sorry.

Can you unwind some turns of the secondaries?

Jamh · 17th July 2004, 03:24 PM

Yes, that is a possibility, but I wanted to know if anyone has tried the other solutions.

pinkmouse · 17th July 2004, 03:31 PM

Dropping current would be very wasteful, and need huge power resistors, as well as not providing very good regulation. Connecting in series would also not work, as it would be difficult to provide a reference earth, and resulting DC caps needed on the output. You would be better using the single supply schema in the datasheet if you wanted to use the traffo you have.

djQUAN · 17th July 2004, 03:32 PM

A little guess may say that your tranny is about 500-800VA.

44V secondaries could give you +/-62V rails. you could use rod's P101 or P68 for that. it is way too high for an LM3876.

Jamh · 18th July 2004, 12:12 AM

I'll take a look at the datasheet again. Thanks.

Doovieman · 20th July 2004, 01:28 AM

you could also build a regulator circuit...MAJOR heat dissipation via some transisitor though...

Doovieman

17th July 2004, 05:50 AM	#1
Jamh diyAudio Member Join Date: Dec 2003 Location: sacramento	Question about a TF I have a toroidal TF with a single primary, and dual 44V secondaries. I'm not sure about its VA rating but the thing is big (6x6x3, 18cable). I was thinking about using it with Brian's boards. Any suggestions as to the best way? One way might be to use 2 of the power boards in series per secondary. That would give me 22V. Another would be to bleed some of the current to ground via a resistor, but I'd be worried about picking humm.

17th July 2004, 10:54 AM	#2
pinkmouse diyAudio Moderator Join Date: Apr 2002 Location: Chatham, England	That's way to high for a GC, sorry. Can you unwind some turns of the secondaries? __________________ Al I conceive of nothing, in religion, science or philosophy, that is more than the proper thing to wear, for a while. Charles Fort

17th July 2004, 03:31 PM	#4
pinkmouse diyAudio Moderator Join Date: Apr 2002 Location: Chatham, England	Dropping current would be very wasteful, and need huge power resistors, as well as not providing very good regulation. Connecting in series would also not work, as it would be difficult to provide a reference earth, and resulting DC caps needed on the output. You would be better using the single supply schema in the datasheet if you wanted to use the traffo you have. __________________ Al I conceive of nothing, in religion, science or philosophy, that is more than the proper thing to wear, for a while. Charles Fort

20th July 2004, 01:28 AM	#7
Doovieman diyAudio Member Join Date: Jul 2003 Location: Berkeley, California	regulator... you could also build a regulator circuit...MAJOR heat dissipation via some transisitor though... Doovieman

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


	Please consider donating to help us continue to serve you. Ads on/off / Custom Title / More PMs / More album space / Advanced printing & mass image saving

17th July 2004, 03:24 PM	#3
Jamh diyAudio Member Join Date: Dec 2003 Location: sacramento	Yes, that is a possibility, but I wanted to know if anyone has tried the other solutions.

17th July 2004, 03:32 PM	#5
djQUAN diyAudio Member Join Date: May 2004 Location: manila	A little guess may say that your tranny is about 500-800VA. 44V secondaries could give you +/-62V rails. you could use rod's P101 or P68 for that. it is way too high for an LM3876.

18th July 2004, 12:12 AM	#6
Jamh diyAudio Member Join Date: Dec 2003 Location: sacramento	I'll take a look at the datasheet again. Thanks.

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

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
newbie with input tran. question and wiring question	imo	Solid State	0	18th January 2006 10:10 PM
Capacitor Question /question on cap	TunaFish	Tubes / Valves	14	12th January 2004 02:23 AM
PS question - tformer question actually	breguetphile	Chip Amps	2	30th May 2003 01:29 PM
old speaker question, bullet midrange question & link to speaker project	wallijonn	Multi-Way	10	5th November 2002 06:03 AM

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