It is currently Tue Mar 17, 2020 12:34 am

All times are UTC - 7 hours



Post new topic Reply to topic  [ 23 posts ]  Go to page Previous  1, 2
Go to page Previous  1, 2
Author Message
Post subject: Re: 2003 Fender Hot Rod Deluxe with major sound loss
Posted: Fri Feb 08, 2013 4:06 pm
Offline
Rock Star
Rock Star

Joined: Mon Apr 05, 2010 2:37 pm
Posts: 8708
Location: Natural Bridge, Virginia
escaife58 wrote:
I had no idea what you were talking about so I called my buddy up again. He said we were reading between 300-400 VOLTS on the caps. Then when we unplugged the amp the caps reading would drop to 12-13 VOLTS.


Slow down. You may not have a problem.

Did your "robot" guy bother to look at the amp schematic? Did he measure across EACH high voltage power supply cap? There are four of them.

http://support.fender.com/schematics/gu ... ematic.pdf

Notice that the spec for B+ is 431 VDC. As you go down the chain, the voltage drops to 345 VDC. Those voltages can vary slightly depending on how the power amp tubes are biased. So, you need to confirm what the reading was across each cap, not just that they were "reading between 300-400 VOLTS".

As far as the voltage dropping to 12 to 13 volts, again, did he measure across each cap? How long did it take for the voltage to drop down to that level? I Have found that the power supply caps in my Blues Deluxe Reissue will discharge from 400+ VDC to below 20 VDC within a couple of minutes after the amp is turned off and unplugged. This is perfectly normal in many amps.

In any case, I strongly recommend that you take the amp to a qualified amp tech. Hopefully your friend knows more about building robots than he does about tube guitar amps. :roll:

_________________
Bill

Image


Last edited by bluesky636 on Fri Feb 08, 2013 6:42 pm, edited 1 time in total.

Top
Profile
Fender Play Winter Sale 2020
Post subject: Re: 2003 Fender Hot Rod Deluxe with major sound loss
Posted: Fri Feb 08, 2013 5:55 pm
Offline
Professional Musician
Professional Musician
User avatar

Joined: Thu Oct 14, 2010 8:54 am
Posts: 1179
Location: Florida
bluesky636 wrote:
Hopefully our friend knows more about building robots than he does about tube guitar amps. :roll:


I've heard some of those robots talk, and they have lousy tone. Kind of electronic sounding. 8)

Art


Top
Profile
Post subject: Re: 2003 Fender Hot Rod Deluxe with major sound loss
Posted: Fri Feb 08, 2013 9:05 pm
Offline
Hobbyist
Hobbyist

Joined: Thu Feb 07, 2013 10:41 am
Posts: 10
Yes my "robot" guy checked all four caps, yes they all read different. Yes he consulted the schematic. I obviously don't know a damn thing about circuit boards and resistors, caps, etc. So some things got lost in translation, the guy looked it over for me and checked the caps, but we both agreed that we didn't know if the caps should discharge that quickly, and I have a cap that is a bit loose on the board, again we didn't want to take chances so he recommended what you have; To take it to a tech. I came here to ask advice on a subject I knew little about. I live an hour away from the nearest tech and wanted to make sure I wasn't overlooking a simple fix that my buddy could handle. I appreciate those who tried to help in this thread.


Top
Profile
Post subject: Re: 2003 Fender Hot Rod Deluxe with major sound loss
Posted: Sat Feb 09, 2013 3:09 am
Offline
Rock Icon
Rock Icon
User avatar

Joined: Fri Feb 05, 2010 4:31 am
Posts: 14049
Location: Province de Québec, Canada
escaife58 wrote:
but we both agreed that we didn't know if the caps should discharge that quickly,

and I have a cap that is a bit loose on the board, again we didn't want to take chances so he recommended what you have; thread.


Yes Capacitor should discharge quickly with no power on the amp

Capacitor loose on the board !!!! Check if is its solder are broken , this mignt your problem ,reading 300 to 400 Volts


Top
Profile
Post subject: Re: 2003 Fender Hot Rod Deluxe with major sound loss
Posted: Sat Feb 09, 2013 6:05 am
Offline
Rock Star
Rock Star

Joined: Mon Apr 05, 2010 2:37 pm
Posts: 8708
Location: Natural Bridge, Virginia
stratele52 wrote:
escaife58 wrote:
but we both agreed that we didn't know if the caps should discharge that quickly,

and I have a cap that is a bit loose on the board, again we didn't want to take chances so he recommended what you have; thread.


Yes Capacitor should discharge quickly with no power on the amp

Capacitor loose on the board !!!! Check if is its solder are broken , this mignt your problem ,reading 300 to 400 Volts


The power supply caps in the HRD are stuck to the PCB with silicone adhesive (at least they are in my BDRI and the amps are in the same family so the HRD caps probably are also). It takes a significant effort to break through that stuff and cause a "loose" cap. Damage would be quite obvious.

_________________
Bill

Image


Top
Profile
Post subject: Re: 2003 Fender Hot Rod Deluxe with major sound loss
Posted: Sat Feb 09, 2013 6:32 am
Offline
Rock Icon
Rock Icon
User avatar

Joined: Fri Feb 05, 2010 4:31 am
Posts: 14049
Location: Province de Québec, Canada
That is what I think bluesky636


Top
Profile
Post subject: Re: 2003 Fender Hot Rod Deluxe with major sound loss
Posted: Sat Feb 09, 2013 9:01 am
Offline
Rock Icon
Rock Icon
User avatar

Joined: Tue Jun 29, 2010 1:20 pm
Posts: 9640
Location: Indiana
Art1 wrote:
bluesky636 wrote:
Hopefully our friend knows more about building robots than he does about tube guitar amps. :roll:


I've heard some of those robots talk, and they have lousy tone. Kind of electronic sounding. 8)

Art


I really like the sounds of a smoothly working assembly line robot. The repetitive, melodic, whirs, whizzes and hums are music to my ears. Think of the mechanical cash register sounds on the intro to Pink Floyd's - Money, and how nicely the music matches up to it. I used to imagine various tunes that went along with the rhythmic beats of assembly lines. :)

_________________
---> "The amp should be SWITCHED OFF AND UNPLUGGED before you do this!" <---

Por favor, disculpe mi español, no se llega a la práctica con mucha frecuencia.


Top
Profile
Post subject: Re: 2003 Fender Hot Rod Deluxe with major sound loss
Posted: Mon Feb 11, 2013 8:48 am
Offline
Hobbyist
Hobbyist

Joined: Tue Jul 19, 2011 10:16 pm
Posts: 25
few months ago, I had a problem very similar to yours. my HRDLx was a broken solder in capacitors and one resistor burned.


Top
Profile
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 23 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: