It is currently Mon Mar 16, 2020 4:49 pm

All times are UTC - 7 hours



Post new topic Reply to topic  [ 22 posts ]  Go to page Previous  1, 2
Go to page Previous  1, 2
Author Message
Post subject:
Posted: Mon Jun 28, 2010 10:51 am
Offline
Hobbyist
Hobbyist
User avatar

Joined: Mon Jun 28, 2010 6:56 am
Posts: 12
Location: Clearwater,Florida
Take a look back before the ground switch at the mains input. One wire is going to the PT primary and the other is fused and going to the PT primary. The AC for power switch on circuit is already completed for the PT to operate all secondary voltages. The ground switch and .047 cap are on the primary side of the PT not the secondary side of the PT. The PS caps dont come into play here. The ground switch is just a -+ polarity thing. You could remove the .047 cap and ground switch all together and the amp will function without either one of them. It is not needed. A thoughtful idea by Leo but not needed. Thats why it is called the death cap. It's function was to further help filter A/C ripple. Not benificial after all. Do you see in the schematic i posted how this works?


Top
Profile
Fender Play Winter Sale 2020
Post subject:
Posted: Mon Jun 28, 2010 12:05 pm
Offline
Rock Icon
Rock Icon
User avatar

Joined: Fri Feb 05, 2010 4:31 am
Posts: 14049
Location: Province de Québec, Canada
Nices pictures triodeamplification, thank's

The caps you call "death cap" is a line bypass cap. It should be 1Kv to 5 Kv and no more than .05 mfd

( from the book : The how and why as gar sees it, write by Gar Gillies page55).
You know that Gar Gillies built Garnet amps


Top
Profile
Post subject:
Posted: Mon Jun 28, 2010 12:44 pm
Offline
Hobbyist
Hobbyist
User avatar

Joined: Mon Jun 28, 2010 6:56 am
Posts: 12
Location: Clearwater,Florida
Retroverbial is right though it should be at least a 600V (For GP) cap even though on this particular amp it is still on the primary side of the PT and no B+ is on this side of the circuit for a surge. 125VAC surge is common but wont generally deliver enough voltage to matter. That is unless you have a FPL power worker try to remove a broken meter that shorts out and takes your TV's and stereo with it. They bought me all new appliances for Xmas in 2004. They sent me a big check. I was surprised how fast they took care of me

_________________
triodeamplification


Top
Profile
Post subject:
Posted: Mon Jun 28, 2010 7:43 pm
Offline
Professional Musician
Professional Musician

Joined: Fri Jun 26, 2009 6:53 pm
Posts: 2252
Location: Harvard IL
Very interesting ! Has anyone looked inside a Super Twin to see which cap is in there ? It's possible the schem is a mis-print. But,yeah I'd remove that part of the circuit. From what I've read, those .047/600V caps were a special design, made to fail open. But still not worth taking a chance ! Nice pics, Triode and welcome to the forum. Hey Stratele, never seen the Garnet amps, but have read that they are really built to last. I'll have to see about getting that book. Art

_________________
None of Us are free, if One of Us is chained !


Top
Profile
Post subject:
Posted: Tue Jun 29, 2010 2:13 am
Offline
Hobbyist
Hobbyist
User avatar

Joined: Mon Jun 28, 2010 6:56 am
Posts: 12
Location: Clearwater,Florida
Thanks aclempoppi. I enjoy being on many forums. Just dont always get a chance to put in my 2 cents

_________________
triodeamplification


Top
Profile
Post subject:
Posted: Tue Jun 29, 2010 2:55 am
Offline
Rock Icon
Rock Icon
User avatar

Joined: Fri Feb 05, 2010 4:31 am
Posts: 14049
Location: Province de Québec, Canada
Image

Image

aclempoppi, Garnet amp was made in '70 and was use by the Guess Who, canadian band, with Randy Bachman.
They are very well built; point to point
You can order the book only by e-mail


Top
Profile
Post subject:
Posted: Tue Jun 29, 2010 10:14 am
Offline
Professional Musician
Professional Musician

Joined: Fri Jun 26, 2009 6:53 pm
Posts: 2252
Location: Harvard IL
Stratele, Thanks for the info on Mr. Gillies book ! Art

_________________
None of Us are free, if One of Us is chained !


Top
Profile
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 22 posts ]  Go to page Previous  1, 2
Go to page Previous  1, 2

All times are UTC - 7 hours

Fender Play Winter Sale 2020

Who is online

Users browsing this forum: No registered users and 2 guests


You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum

Search for:
Jump to: