Problem with my G5 amp
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- G5 bidouilleur
- Messages : 19
- Enregistré le : 06 mars 2024, 23:09
Problem with my G5 amp
Good Today,
I would like to describe my adventure with G5.
Last year i build my first amp. Everything was quite good, but i placed false both trafos and lamps. I decided to rebuild IT. This year i ordered new chassis, took everything from the old one and placed in the new chassis.
The problem is, now it does not work, it means i hear nothing im speaker and el34 is warm extremely.
Thank you very much for the answer.
Best regards
I would like to describe my adventure with G5.
Last year i build my first amp. Everything was quite good, but i placed false both trafos and lamps. I decided to rebuild IT. This year i ordered new chassis, took everything from the old one and placed in the new chassis.
The problem is, now it does not work, it means i hear nothing im speaker and el34 is warm extremely.
Thank you very much for the answer.
Best regards
- Fichiers joints
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VID_20240307_064115.mp4
- (1.59 Mio) Téléchargé 896 fois
Re: Problem with my G5 amp
Hi,
First on the video, it seem there is a bit sound ( "ssshhhh" ), but no signal ...
The power tube don't seem to be "over-biaised" . In such a case, the exterior plate ( metallic part inside the tube ), would be a bit red ... It's normal a power tube get warm ...
So, in a first step, the best would be to send us all mesures, pin by pin on all the tubes, and biais and supply values ...
First on the video, it seem there is a bit sound ( "ssshhhh" ), but no signal ...
The power tube don't seem to be "over-biaised" . In such a case, the exterior plate ( metallic part inside the tube ), would be a bit red ... It's normal a power tube get warm ...
So, in a first step, the best would be to send us all mesures, pin by pin on all the tubes, and biais and supply values ...
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- G5 bidouilleur
- Messages : 19
- Enregistré le : 06 mars 2024, 23:09
Re: Problem with my G5 amp
Ok, i will do this when i come back to home. Thank you very much.
- McColson
- Admin du site
- Messages : 7971
- Enregistré le : 07 nov. 2004, 1:00
- Localisation : La Celle sur Morin
- Contact :
Re: Problem with my G5 amp
I move this topic to the international board 

-
- G5 bidouilleur
- Messages : 19
- Enregistré le : 06 mars 2024, 23:09
Re: Problem with my G5 amp
McColson, thank you very much 
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- G5 bidouilleur
- Messages : 19
- Enregistré le : 06 mars 2024, 23:09
Re: Problem with my G5 amp
On the one foto with red circle, inside this circle i saw a short circuit during turning volume pot. One what i noticed is, when i moved the Brown cable from OT, this circuit and noisy "shhhh..." were off. Maybe this cable is somewhere broken down? Or one or both trafos?
After my measurement PT was hot but without smoke.
Thank you very much for the answer.
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- G5 bidouilleur
- Messages : 19
- Enregistré le : 06 mars 2024, 23:09
Re: Problem with my G5 amp
Good Today, i'm gonna sloder everything once more. Then we will see. It's not possible that, everything worked in old chassis and now, in new one, does'nt work. Probably i made a mistake somewhere.
Best regards
Best regards
Re: Problem with my G5 amp
Hi Papa_Mateo,
Checking every solder is a good idea.
By the way, in the first picture above, I was wondering is the resistor was soldered onto the jack; I added a green circle to show where. Good luck (and be patient) !
Checking every solder is a good idea.

By the way, in the first picture above, I was wondering is the resistor was soldered onto the jack; I added a green circle to show where. Good luck (and be patient) !
dilet
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- G5 bidouilleur
- Messages : 19
- Enregistré le : 06 mars 2024, 23:09
Re: Problem with my G5 amp
Good Today,
This is line out jack and i soldered it onto the signal pin. Do you think IT could be a problem?
I decided to check everything once more. I will save much more time.
Thank you very much
This is line out jack and i soldered it onto the signal pin. Do you think IT could be a problem?
I decided to check everything once more. I will save much more time.
Thank you very much
Re: Problem with my G5 amp
My question was: is there a weld (hard to see on the picture) ?
More generally, I find your welds (those on the picture) not loaded enough with solder (no offense
). 
More generally, I find your welds (those on the picture) not loaded enough with solder (no offense


dilet
- McColson
- Admin du site
- Messages : 7971
- Enregistré le : 07 nov. 2004, 1:00
- Localisation : La Celle sur Morin
- Contact :
Re: Problem with my G5 amp
Can you send a picture at all the wiring ?
-
- G5 bidouilleur
- Messages : 19
- Enregistré le : 06 mars 2024, 23:09
Re: Problem with my G5 amp
I can send, but i decided to make it once more, with new plate etc.
Re: Problem with my G5 amp
If you are rewiring, it would be advisable to use different colored cables as follows:
- earth in green-yellow
- brown and blue for mains
- ground in black (every ground and only ground)
- HV power in red (A+, B+, ...)
- 6.3V (heating) in green with the two wires twisted
- one (or more) color for anything else
This complicates the wiring a bit but provides valuable assistance when making modifications, upgrades or troubleshooting.
As you previously said, if it worked in the old case, there's no reason why it wouldn't work in the new one (except bad soldering or bad wiring
).
- earth in green-yellow
- brown and blue for mains
- ground in black (every ground and only ground)
- HV power in red (A+, B+, ...)
- 6.3V (heating) in green with the two wires twisted
- one (or more) color for anything else
This complicates the wiring a bit but provides valuable assistance when making modifications, upgrades or troubleshooting.
As you previously said, if it worked in the old case, there's no reason why it wouldn't work in the new one (except bad soldering or bad wiring

dilet
-
- G5 bidouilleur
- Messages : 19
- Enregistré le : 06 mars 2024, 23:09
Re: Problem with my G5 amp
exactly, i will do it once more. Maybe soldering somewhere is broken etc. I'm gonna change also the cables. I will inform if it works
It could be a small problem.
Thank you very much and we are in touch
It could be a small problem.
Thank you very much and we are in touch