• WARNING: Tube/Valve amplifiers use potentially LETHAL HIGH VOLTAGES.
    Building, troubleshooting and testing of these amplifiers should only be
    performed by someone who is thoroughly familiar with
    the safety precautions around high voltages.

Help for a Output Transfo problem

Status
This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.
Hi,

I am experiencing some troubles with a PP project using two transformers with a different behaviour.
The good one is perfectly working while the second is showing a lower power with all the electrical parameters like the other stage.
Testing the transfos I noticed that sending a tone to output side of the good one, I have the elevated signal on the primary side and doing the same with the bad transfo, when I apply the signal to the output side, the signal is lowered almost to zero showing a distorced shape on the output side itself.
The resistance values are similar for both transfos.
The output impedance is made with a series-parallel assembling of different windings that have to respect the correct phase.
I guess that I have the bad transfo with a wrong colour code, this could justify the electrical resistance as well as a mess of phase-counter phase assembling giving all these troubles I mentioned before.
Attached you will find the output wiring for 8 ohms.
Do you think my assumptions are right?
Thanks in advance
 

Attachments

  • output stage.jpg
    output stage.jpg
    17.5 KB · Views: 85
HI SY,
I was just going to bed, it is 1.40 a.m. here in Milano :)
I was thinking to dismount the transfo, send a square tone to the primary and check one by one all the separated wirngs of the secondary to verify whether or not there is the coulour code mistake
Is that correct?
Ciao
 
Status
This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.