I have a Fender (tweed) Blues DeVille Re-Issue on my bench.The 1st thing I noticed was the pilot bulb was not working.I took the bulb out,but I'm not sure how to check if it's bad?I think I read somewhere,that it doesn't matter if the bulbs bad,it's not connected to the PCB.Which leads me to my next issue..I plugged in a chord,and there's a major loss in volume.Sounds like it's barely on 1.I checked the tubes,they seem to be ok.I looked inside to see if anything looked burnt,but everything looks fine.Checked and made sure all of the connectors were snug.I'm at a loss.Anybody have any ideas of what I can check?Thanks in advance!Fender Blues DeVille 4x10 Re-Issue Problem
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Fender Blues DeVille 4x10 Re-Issue Problem
This is my 1st post in the forum I have a Fender (tweed) Blues DeVille Re-Issue on my bench.The 1st thing I noticed was the pilot bulb was not working.I took the bulb out,but I'm not sure how to check if it's bad?I think I read somewhere,that it doesn't matter if the bulbs bad,it's not connected to the PCB.Which leads me to my next issue..I plugged in a chord,and there's a major loss in volume.Sounds like it's barely on 1.I checked the tubes,they seem to be ok.I looked inside to see if anything looked burnt,but everything looks fine.Checked and made sure all of the connectors were snug.I'm at a loss.Anybody have any ideas of what I can check?Thanks in advance!
I have a Fender (tweed) Blues DeVille Re-Issue on my bench.The 1st thing I noticed was the pilot bulb was not working.I took the bulb out,but I'm not sure how to check if it's bad?I think I read somewhere,that it doesn't matter if the bulbs bad,it's not connected to the PCB.Which leads me to my next issue..I plugged in a chord,and there's a major loss in volume.Sounds like it's barely on 1.I checked the tubes,they seem to be ok.I looked inside to see if anything looked burnt,but everything looks fine.Checked and made sure all of the connectors were snug.I'm at a loss.Anybody have any ideas of what I can check?Thanks in advance!Soupbone
Re: Fender Blues DeVille 4x10 Re-Issue Problem
If you don't know how to test a lamp bulb , do you think you'll be able to make the test needed to fix your amp?
You'll need a multimeter first, then learn to test the bulb. Maybe fund a local tech and learn a little on this amp.
You'll need a multimeter first, then learn to test the bulb. Maybe fund a local tech and learn a little on this amp.
Re: Fender Blues DeVille 4x10 Re-Issue Problem
Billyz, I was thinking the exact same thing!billyz wrote:If you don't know how to test a lamp bulb , do you think you'll be able to make the test needed to fix your amp?
You'll need a multimeter first, then learn to test the bulb. Maybe fund a local tech and learn a little on this amp.
TM
Re: Fender Blues DeVille 4x10 Re-Issue Problem
billyz wrote:If you don't know how to test a lamp bulb , do you think you'll be able to make the test needed to fix your amp?
You'll need a multimeter first, then learn to test the bulb. Maybe fund a local tech and learn a little on this amp.
Last edited by soupbone on Sun Apr 13, 2014 5:55 pm, edited 1 time in total.
Soupbone
Re: Fender Blues DeVille 4x10 Re-Issue Problem
billyz wrote:If you don't know how to test a lamp bulb , do you think you'll be able to make the test needed to fix your amp?
You'll need a multimeter first, then learn to test the bulb. Maybe fund a local tech and learn a little on this amp.
Last edited by soupbone on Sun Apr 13, 2014 3:43 pm, edited 1 time in total.
Soupbone
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Stevem
- Posts: 5144
- Joined: Fri Jan 24, 2014 3:01 pm
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Re: Fender Blues DeVille 4x10 Re-Issue Problem
Pack it and take it over to your buddy and direct him to here if he has issues with it still.
When I die, I want to go like my Grandfather did, peacefully in his sleep.
Not screaming like the passengers in his car!
Cutting out a man's tongue does not mean he’s a liar, but it does show that you fear the truth he might speak about you!
Not screaming like the passengers in his car!
Cutting out a man's tongue does not mean he’s a liar, but it does show that you fear the truth he might speak about you!
Re: Fender Blues DeVille 4x10 Re-Issue Problem
Cool site.I was hoping someone has had this same problem,and maybe had some ideas I could try?I know enough about amps to bleed the caps,and not get the crap shocked of me!If it requires using an oscilloscope,I'll have to take it to my friend that knows a lot about amps.I was hoping it would be something i that i could fix,because i don't have a disposable income.Thanks for the replies!billyz wrote:If you don't know how to test a lamp bulb , do you think you'll be able to make the test needed to fix your amp?
You'll need a multimeter first, then learn to test the bulb. Maybe fund a local tech and learn a little on this amp.
Soupbone
Re: Fender Blues DeVille 4x10 Re-Issue Problem
Most everyone here can help you fix your amp. But you would need to know enough to use a multimeter and test the 6.3vac light bulb.
Ok, many of these have blown phase invertor plate resistors. If a power tube shorted it may have taken out the screen resistor. The channel switching circuit has large power supply dropping resistors that overheat and desolder themselves from the board. Solder traces crack on the input jacks. The preamp out power amp in jacks get dirty and interrupt the connection. Could even be a bad speaker , etc etc etc. just because the tubes light up does not mean they are good. Test, test, test. Get the schematic and test from the power supply to the preamp. Do a pop test. Signal trace from the input. Or the output , your choice.
A few ideas for you, different ways to diagnose. I always test the power supply first. Could be a bad preamp tube, do some substitutions with a known good 12ax7. Etc etc etc.
Hope this helps you. Enjoy the wonderful world of tube amplification . I do.
Ok, many of these have blown phase invertor plate resistors. If a power tube shorted it may have taken out the screen resistor. The channel switching circuit has large power supply dropping resistors that overheat and desolder themselves from the board. Solder traces crack on the input jacks. The preamp out power amp in jacks get dirty and interrupt the connection. Could even be a bad speaker , etc etc etc. just because the tubes light up does not mean they are good. Test, test, test. Get the schematic and test from the power supply to the preamp. Do a pop test. Signal trace from the input. Or the output , your choice.
A few ideas for you, different ways to diagnose. I always test the power supply first. Could be a bad preamp tube, do some substitutions with a known good 12ax7. Etc etc etc.
Hope this helps you. Enjoy the wonderful world of tube amplification . I do.
Re: Fender Blues DeVille 4x10 Re-Issue Problem
What happened to that website for Fender HRD repairs it had all the common symptoms and repairs listed?
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Stevem
- Posts: 5144
- Joined: Fri Jan 24, 2014 3:01 pm
- Location: 1/3rd the way out one of the arms of the Milkyway.
Re: Fender Blues DeVille 4x10 Re-Issue Problem
One easy test to make to see if any drive signal is hitting the power tubes is to view the center blue glowing section of the power tubes in a dark room while you play thru the amp.
If you see changes in brite ness in that center section of the tube,then the tubes are being drivin pretty good and the amp should have near normal volume,if it does not than the output transformer is likely bad.
If you see no changes in lightness in the tubes than it's not getting signal and problems are else where.
This is assuming that the amp has B+voltage that you check by testing for over 400 volts DC on pin 3 and 4 of either output tube.
If you see changes in brite ness in that center section of the tube,then the tubes are being drivin pretty good and the amp should have near normal volume,if it does not than the output transformer is likely bad.
If you see no changes in lightness in the tubes than it's not getting signal and problems are else where.
This is assuming that the amp has B+voltage that you check by testing for over 400 volts DC on pin 3 and 4 of either output tube.
When I die, I want to go like my Grandfather did, peacefully in his sleep.
Not screaming like the passengers in his car!
Cutting out a man's tongue does not mean he’s a liar, but it does show that you fear the truth he might speak about you!
Not screaming like the passengers in his car!
Cutting out a man's tongue does not mean he’s a liar, but it does show that you fear the truth he might speak about you!
Re: Fender Blues DeVille 4x10 Re-Issue Problem
Thanks Billy Z!I am pretty good with a DMM.I've just never had to test a pilot bulb.I'll find out today,and try with my friend get to the bottom of this amp.Thanks!billyz wrote:Most everyone here can help you fix your amp. But you would need to know enough to use a multimeter and test the 6.3vac light bulb.
Ok, many of these have blown phase invertor plate resistors. If a power tube shorted it may have taken out the screen resistor. The channel switching circuit has large power supply dropping resistors that overheat and desolder themselves from the board. Solder traces crack on the input jacks. The preamp out power amp in jacks get dirty and interrupt the connection. Could even be a bad speaker , etc etc etc. just because the tubes light up does not mean they are good. Test, test, test. Get the schematic and test from the power supply to the preamp. Do a pop test. Signal trace from the input. Or the output , your choice.
A few ideas for you, different ways to diagnose. I always test the power supply first. Could be a bad preamp tube, do some substitutions with a known good 12ax7. Etc etc etc.
Hope this helps you. Enjoy the wonderful world of tube amplification . I do.
Soupbone
Re: Fender Blues DeVille 4x10 Re-Issue Problem
Thanks!Stevem wrote:One easy test to make to see if any drive signal is hitting the power tubes is to view the center blue glowing section of the power tubes in a dark room while you play thru the amp.
If you see changes in brite ness in that center section of the tube,then the tubes are being drivin pretty good and the amp should have near normal volume,if it does not than the output transformer is likely bad.
If you see no changes in lightness in the tubes than it's not getting signal and problems are else where.
This is assuming that the amp has B+voltage that you check by testing for over 400 volts DC on pin 3 and 4 of either output tube.
Soupbone
Re: Fender Blues DeVille 4x10 Re-Issue Problem
If you put a 12.6 volt bulb in the pilot light, it will only be half a bright but it does help with the tone--it is a more compressed tone. I tried it and I can play in my apartment without bothering the neighbors.
What?
Re: Fender Blues DeVille 4x10 Re-Issue Problem
This must be the ultimate light bulb limiter !Jana wrote:If you put a 12.6 volt bulb in the pilot light, it will only be half a bright but it does help with the tone--it is a more compressed tone. I tried it and I can play in my apartment without bothering the neighbors.
Fender Blues Deville 4x10 Problem
Well,Me and My Friend looked at the amp yesterday,and one of the Tubes was red-plating.Going to get a new matched set of 6L6's,re-bias it and then see what happens.If it still has the huge loss in volume,it could be the cheap ribbon cable that's going to the power tubes.I'll report back!(p
s. the pilot bulb is bad.)
s. the pilot bulb is bad.)
Soupbone