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Problem with my G5 amp

Posté : 07 mars 2024, 6:42
par Papa_Mateo
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

Re: Problem with my G5 amp

Posté : 07 mars 2024, 8:35
par louphil
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 ...

Re: Problem with my G5 amp

Posté : 07 mars 2024, 8:50
par Papa_Mateo
Ok, i will do this when i come back to home. Thank you very much.

Re: Problem with my G5 amp

Posté : 07 mars 2024, 11:39
par McColson
I move this topic to the international board ;-)

Re: Problem with my G5 amp

Posté : 07 mars 2024, 12:59
par Papa_Mateo
McColson, thank you very much 🤘

Re: Problem with my G5 amp

Posté : 07 mars 2024, 20:46
par McColson
My pleasure !

Re: Problem with my G5 amp

Posté : 07 mars 2024, 21:48
par Papa_Mateo
IMG_20240307_214008.jpg
Good Evening, i worked with multimeter and i think i did IT well.
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.

Re: Problem with my G5 amp

Posté : 09 mars 2024, 11:20
par Papa_Mateo
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 🤘

Re: Problem with my G5 amp

Posté : 10 mars 2024, 19:40
par dilet
Hi Papa_Mateo,
Checking every solder is a good idea. :good:
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.
Soudures.jpg
Good luck (and be patient) !

Re: Problem with my G5 amp

Posté : 11 mars 2024, 9:16
par Papa_Mateo
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

Re: Problem with my G5 amp

Posté : 12 mars 2024, 23:29
par dilet
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 :oops:). :think:

Re: Problem with my G5 amp

Posté : 13 mars 2024, 9:23
par McColson
Can you send a picture at all the wiring ?

Re: Problem with my G5 amp

Posté : 13 mars 2024, 15:18
par Papa_Mateo
I can send, but i decided to make it once more, with new plate etc.

Re: Problem with my G5 amp

Posté : 14 mars 2024, 23:40
par dilet
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 :mrgreen:).

Re: Problem with my G5 amp

Posté : 15 mars 2024, 8:46
par Papa_Mateo
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 💪