It is currently Mon Mar 16, 2020 8:55 pm

All times are UTC - 7 hours



Post new topic Reply to topic  [ 5 posts ] 
Author Message
Post subject: Fender Super Amp 90's
Posted: Mon Aug 11, 2014 6:47 pm
Offline
Hobbyist
Hobbyist

Joined: Mon Apr 19, 2010 9:59 pm
Posts: 56
Hey,
Anyone out there had and experience with the Fender Super?
It's not a Concert...it's a Super with 4-10 cab combo.
Owner switched out all the pre amp tubes and the problem persists.
We have tried different speakers to see if the problem was still there.
When you play a note or chord and let it sustain there is a fuzz tone like distortion.
Actually just playing a guitar the distortion is there no matter what channel.
Someone told me the PS caps may be the problem.
I did find that C44 and C45(radials) where quite bulged on the ends.
Replaced....but not the cure.
Also tested C43 and 44. They tested kinda odd on my Eico.
Replaced them...not the problem.
Any ideas out there?
Thanks folks!
tube dude


Top
Profile
Fender Play Winter Sale 2020
Post subject: Re: Fender Super Amp 90's
Posted: Tue Aug 12, 2014 1:19 am
Offline
Rock Icon
Rock Icon
User avatar

Joined: Fri Feb 05, 2010 4:31 am
Posts: 14049
Location: Province de Québec, Canada
tube dude wrote:
Hey,
Anyone out there had and experience with the Fender Super?
It's not a Concert...it's a Super with 4-10 cab combo.
Owner switched out all the pre amp tubes and the problem persists.

Be sure all tubes are good , don't trust owner

We have tried different speakers to see if the problem was still there.
When you play a note or chord and let it sustain there is a fuzz tone like distortion.
Actually just playing a guitar the distortion is there no matter what channel.
Someone told me the PS caps may be the problem.
I did find that C44 and C45(radials) where quite bulged on the ends.
Replaced....but not the cure.
Also tested C43 and 44. They tested kinda odd on my Eico.
Which Eico ?

Replaced them...not the problem.
Any ideas out there?
Thanks folks!
tube dude



Hard to tell without hearing it ,
Any link for schematic , the one I have it is '90 area Super Amp .

Could be tubes ,
Phase inverter circuits , some bad resistors ,
Output transformer.
Power Supply ; check voltages DC and AC too on filter cap

Give link for your amp and / or year ....


Top
Profile
Post subject: Re: Fender Super Amp 90's
Posted: Tue Aug 12, 2014 2:24 pm
Offline
Hobbyist
Hobbyist

Joined: Mon Apr 19, 2010 9:59 pm
Posts: 56
Rock Star,
I'll see if I can put the link on here for the schematic.....nope!
I believe I can send it thru email...If you are willing to send me your address!
I can't seem to get the link from my Fender email reply to" this message"....
The schematic is a PDF..I'm stuck!
Anyway.......
When playing you can hear this distortion.
After I replaced the bulged caps and the 2 that were iffy,
the distortion is still there.
What is very difficult, is to try and check voltages via test points. You have to totally remove the main circuit board and the control circuit from the chassis. All the components and the test points are on the top of the board. There isn't a way to keep all the wires connected and turn it on to test...Man I am stumped!
Let me know about you email....
Thanks Rock Star!
tube dude


Top
Profile
Post subject: Re: Fender Super Amp 90's
Posted: Tue Aug 12, 2014 2:38 pm
Offline
Hobbyist
Hobbyist

Joined: Mon Apr 19, 2010 9:59 pm
Posts: 56
Rock Star,
New tubes were tried plus different cabs...same distortion.
That I know for sure.
I replaced C 42,43,44 and 45. Now there seems to be more distortion!
My cap tester is an Eico 950B.
I guess I need to figure out how to hook this all up, with the circuit boards out and power it on to make any tests...this will be a challenge!
Well here I go.
tube dude


Top
Profile
Post subject: Re: Fender Super Amp 90's
Posted: Wed Aug 13, 2014 1:34 am
Offline
Rock Icon
Rock Icon
User avatar

Joined: Fri Feb 05, 2010 4:31 am
Posts: 14049
Location: Province de Québec, Canada
First ,check all resistors in Phase Inverter circuit . You must disconnect one end to read them.

2- Read all power supply voltage


Top
Profile
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 5 posts ] 

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: