Welcome, Guest. Please login or register.
Did you miss your activation email?
November 22, 2024, 02:45:47 PM
Home Help Search Login Register
News: Ceriatone Forums are up and running!!!
 
Guests please register
Note: If you want to help you can donate to keep the forums alive.



Do you want to advertise on this forum ? Send me a private message.

Amplified Parts
+  Ceriatone Forum
|-+  Ceriatone
| |-+  Overtone
| | |-+  No OD - UPDATED		 « previous next »
Pages: [1] 2 Go Down Print
Author Topic: No OD - UPDATED  (Read 10695 times)
bobgoblin
Jr. Member
**
Offline Offline

Posts: 74


View Profile
« on: August 22, 2010, 05:22:37 AM »
So, at rehearsal today my 50w OTS just cut out. After troubleshooting tubes, speakers, etc, I switched the OD off at the pedal. To my surprise, I had sound again, just no OD. The PAB still works, but even with the pedal disconnected I cannot manually switch to OD-I get no OD sound at all, just silence. OD off, even with PAB, sound. Anyone care to help me out, suggestions or whatever. Thanks!
« Last Edit: August 23, 2010, 09:14:26 AM by bobgoblin » Logged
boldaslove6789
Sr. Member
****
Offline Offline

Gender: Male
Posts: 310


I'm never too loud, HAHAHA


View Profile WWW
« Reply #1 on: August 22, 2010, 05:35:59 AM »
Have you tried replacing the OD tube ? I would try that........
Logged
-Greg D. Clark

Stop searching for tone, INVENT IT!

http://www.funkymunkpedals.com/
Pedals That Speak!

 http://www.youtube.com/GDClarkProject
bobgoblin
Jr. Member
**
Offline Offline

Posts: 74


View Profile
« Reply #2 on: August 22, 2010, 06:08:27 AM »
Yeah, I've replaced v1 & v2 & replaced he PI with a known good tube. Thanks, tho!
Logged
bluesfendermanblues
Sr. Member
****
Offline Offline

Gender: Male
Posts: 452



View Profile
« Reply #3 on: August 22, 2010, 08:11:16 AM »
Check the wires to/from the OD relay.
Logged
Respect for the big guy's work....we're at this part of the forum because of HAD's amps.
bobgoblin
Jr. Member
**
Offline Offline

Posts: 74


View Profile
« Reply #4 on: August 22, 2010, 10:03:42 AM »
Thanks!  I'll do that later today.
Logged
bobgoblin
Jr. Member
**
Offline Offline

Posts: 74


View Profile
« Reply #5 on: August 23, 2010, 02:10:30 AM »
Update:

Every tube I've tried produces the same results.  Pin voltages are off, though, so other than touching up some solder joints on V2, I'm at a loss...

Any other suggestions?
Logged
bluesfendermanblues
Sr. Member
****
Offline Offline

Gender: Male
Posts: 452



View Profile
« Reply #6 on: August 23, 2010, 05:21:35 AM »
Quote from: bobgoblin on August 23, 2010, 02:10:30 AM
Update:

Every tube I've tried produces the same results.  Pin voltages are off, though, so other than touching up some solder joints on V2, I'm at a loss...

Any other suggestions?

Check the power supply to V2, is it broken of somewhere?
Logged
Respect for the big guy's work....we're at this part of the forum because of HAD's amps.
bobgoblin
Jr. Member
**
Offline Offline

Posts: 74


View Profile
« Reply #7 on: August 23, 2010, 06:51:50 AM »
Thanks, Blues, I appreciate all your help.  I'm new to all this stuff, so tracing connections is very frustrating.  A member of the Amp Garage & TGP known to most D-style players has advised that perhaps the 4.7uf cathode bypass cap has shorted...now to find that & trace the power to V2.

FWIW, Here are my pin voltages on V2:

Pin 1:  185v
Pin 3:  1.645v
Pin 6:  4.29v
Pin 8:  4.28v

Argh!!!
Logged
bobgoblin
Jr. Member
**
Offline Offline

Posts: 74


View Profile
« Reply #8 on: August 23, 2010, 09:21:38 AM »
After chasing the power supply to V2 down, I tested the 150k resistor that feeds the 5uf/180k...measurements are out of range, badly.  So, tomorrow, off to the electronics store for a new resistor & then back to rocking!  (Hopefully...)
Logged
bluesfendermanblues
Sr. Member
****
Offline Offline

Gender: Male
Posts: 452



View Profile
« Reply #9 on: August 23, 2010, 09:52:44 AM »
Quote from: bobgoblin on August 23, 2010, 06:51:50 AM
Thanks, Blues, I appreciate all your help.  I'm new to all this stuff, so tracing connections is very frustrating.  A member of the Amp Garage & TGP known to most D-style players has advised that perhaps the 4.7uf cathode bypass cap has shorted...now to find that & trace the power to V2.

FWIW, Here are my pin voltages on V2:

Pin 1:  185v
Pin 3:  1.645v
Pin 6:  4.29v
Pin 8:  4.28v

Argh!!!

 Pin6 & 8 are way out of range....so your problem is V2b
Logged
Respect for the big guy's work....we're at this part of the forum because of HAD's amps.
bluesfendermanblues
Sr. Member
****
Offline Offline

Gender: Male
Posts: 452



View Profile
« Reply #10 on: August 23, 2010, 09:53:43 AM »
Quote from: bobgoblin on August 23, 2010, 09:21:38 AM
After chasing the power supply to V2 down, I tested the 150k resistor that feeds the 5uf/180k...measurements are out of range, badly.  So, tomorrow, off to the electronics store for a new resistor & then back to rocking!  (Hopefully...)

5uf/180k Huh?Huh?Huh??

you need 5uf/2.2k
Logged
Respect for the big guy's work....we're at this part of the forum because of HAD's amps.
bobgoblin
Jr. Member
**
Offline Offline

Posts: 74


View Profile
« Reply #11 on: August 23, 2010, 10:48:19 AM »
Yes, sorry, I meant to type the 5uf cap and the 180k resistor that follows it (precedes the 100kL pot).
Logged
bobgoblin
Jr. Member
**
Offline Offline

Posts: 74


View Profile
« Reply #12 on: August 23, 2010, 10:07:29 PM »
Well, I replaced the resistor, but it was a bust, the problem remained.  Nik advised I should remove the snubbers, so off they came & now I'm back in action.  Only question is, is there any harm in running the amp at gig volumes for a while until I receive some new parts in the mail?
Logged
bluesfendermanblues
Sr. Member
****
Offline Offline

Gender: Male
Posts: 452



View Profile
« Reply #13 on: August 23, 2010, 10:57:40 PM »
Ok, so the snubbers was the problem ?

You can easily run the amp without snubbers, although it will be pretty harsh in OD mode.
Logged
Respect for the big guy's work....we're at this part of the forum because of HAD's amps.
bobgoblin
Jr. Member
**
Offline Offline

Posts: 74


View Profile
« Reply #14 on: August 23, 2010, 11:32:12 PM »
Thanks, Blues, was just informed 250pf - 270pf is good (RF's values).  I have a 390pf on v2a & a 330pf on v2b for now...we'll see how it works out.

Thanks for all the help!
Logged
Pages: [1] 2 Go Up Print 
« previous next »
Jump to:  


Login with username, password and session length

Powered by MySQL Powered by PHP Powered by SMF 1.1.12 | SMF © 2006-2009, Simple Machines LLC Valid XHTML 1.0! Valid CSS!

CeriaTone Forum is not afiliated with Ceriatone Amplifications. The CeriaTone and name, logo and related trademarks and service marks, owned by CeriaTone. , are registered and/or used in the U.S. and many foreign countries. All other trademarks, service marks, and trade names referenced in this site are the property of their respective owners.