Power transformer for Firefly Amp?

infernal · 2nd January 2011, 02:37 PM

Hi I have a little problem.
Specs for transformers are messing with my head.
Look at the pictures

http://img41.imageshack.us/img41/9471/pic1nb.jpg

http://img209.imageshack.us/img209/3697/pic2zs.jpg

On first it says on secondary 207VAC and after a Gretz it says 265V.
How is that posible?

On other pic there is Hammond transformer. His specs are 190-0-190 on secondary. And again it is 265V after two solid-state diodes

Could someone tell me how it is possible?

MattyAve · 2nd January 2011, 03:50 PM

I think what happens sometimes is, engineers and designers, casually draw up these up - not paying attention to the finer details.

here's a good rules of thumb:

HALF WAVE (one diode) = acV x 1.1 = dcV

FULL WAVE (two diodes w/ grounded CT) = acV x 1.4 x .5 = dcV

FULL WAVE BRIDGE (four diodes, + or - node grounded) = acV x 1.4 = dcV

VictoriaGuy · 2nd January 2011, 04:12 PM

Time to do some studying about rectifiers!
This is very useful:
PSUD2

Zibi · 2nd January 2011, 05:41 PM

"I know nothing about electronics and it's enough to build a tube amplifier."

infernal · 4th January 2011, 09:41 PM

Ya. Thanks. I'm noob. :S

2nd January 2011, 02:37 PM	#1
infernal diyAudio Member Join Date: Nov 2010 Location: Banja Luka	Power transformer for Firefly Amp? Hi I have a little problem. Specs for transformers are messing with my head. Look at the pictures http://img41.imageshack.us/img41/9471/pic1nb.jpg http://img209.imageshack.us/img209/3697/pic2zs.jpg On first it says on secondary 207VAC and after a Gretz it says 265V. How is that posible? On other pic there is Hammond transformer. His specs are 190-0-190 on secondary. And again it is 265V after two solid-state diodes Could someone tell me how it is possible?

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

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
FireFly Single Ended Tetrode	TheGimp	Tubes / Valves	96	17th December 2010 02:10 AM
Firefly, small guitar amp (partial kit)	Astera	Instruments and Amps	1	13th September 2007 04:02 PM
FireFly Amp Question	cwoodall	Tubes / Valves	2	26th November 2005 11:47 PM
Good price on huge power transformer for power amp.	G	Solid State	3	15th September 2002 01:23 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


	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

2nd January 2011, 03:50 PM	#2
MattyAve diyAudio Member Join Date: Aug 2010	I think what happens sometimes is, engineers and designers, casually draw up these up - not paying attention to the finer details. here's a good rules of thumb: HALF WAVE (one diode) = acV x 1.1 = dcV FULL WAVE (two diodes w/ grounded CT) = acV x 1.4 x .5 = dcV FULL WAVE BRIDGE (four diodes, + or - node grounded) = acV x 1.4 = dcV

2nd January 2011, 04:12 PM	#3
VictoriaGuy diyAudio Member Join Date: Dec 2008 Location: Victoria, BC	Time to do some studying about rectifiers! This is very useful: PSUD2

2nd January 2011, 05:41 PM	#4
Zibi diyAudio Member Join Date: Jan 2006 Location: Bialystok	"I know nothing about electronics and it's enough to build a tube amplifier."

4th January 2011, 09:41 PM	#5
infernal diyAudio Member Join Date: Nov 2010 Location: Banja Luka	Ya. Thanks. I'm noob. :S