Here on my desk I have a Vox AC30CC2X (The one with the 2 blue speakers).
It has a strange error, but there are probably others who have seen the error before me.
I refer to the uploaded image.
I have removed the high voltage fuse (FS1), during the entire troubleshooting.
When I turn on the power switch starts the tubes to glow. After 10 - 20 seconds there will be sparks inside the rectifier tube and then the fuse blows FS4 (2 AT). If it was the filtament that was shorted should FS3 blow.
I believe that a spark can be obtained only if there is a short circuit between the high voltage and the 5 volt filament voltage.
Or is there something I have overlooked.
Regards
Benny
It has a strange error, but there are probably others who have seen the error before me.
I refer to the uploaded image.
I have removed the high voltage fuse (FS1), during the entire troubleshooting.
When I turn on the power switch starts the tubes to glow. After 10 - 20 seconds there will be sparks inside the rectifier tube and then the fuse blows FS4 (2 AT). If it was the filtament that was shorted should FS3 blow.
I believe that a spark can be obtained only if there is a short circuit between the high voltage and the 5 volt filament voltage.
Or is there something I have overlooked.
Regards
Benny
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The GZ34 will look like a volcano if there is a short circuit or heavy load on the cathode. Main smoothing capacitor is where I would start looking as you have removed the DC fuse. Or indeed a faulty rectifier valve.
Hi
Yes. I know the capacitors, but I havs removed the high voltage fuse so the center tap is without any connection.
Benny
Yes. I know the capacitors, but I havs removed the high voltage fuse so the center tap is without any connection.
Benny
It could be the rectifier valve breaking down, or something more sinister. Best to go one bit at a time. Keep a note of what you have done and when you clear the fault, all will become obvious.
Yes, remove the GZ34 and see if it holds. Or try a different GZ34.
You may have removed the center tap connection, but there is still 600vf plate to plate, and as the filament warms up the tube, it could cause some problem in the tube to allow current between those plates.
The only thing that will blow FS3 is excess current THROUGH FS3.
You may have removed the center tap connection, but there is still 600vf plate to plate, and as the filament warms up the tube, it could cause some problem in the tube to allow current between those plates.
The only thing that will blow FS3 is excess current THROUGH FS3.
I have seen a gassy rectifier do this. Is there any blue glow in the rectifier? Either way try another tube.
Replace the GZ34 if it is a Chinese or Russian made.
I have changed about a dozen or so in these Voxes with the same symptomes.
I stick with JJ tubes.
Maybe not allways the best, but hey, they do wat they are supposed to do and that's enough for me, the musicshop and the musician.
I have changed about a dozen or so in these Voxes with the same symptomes.
I stick with JJ tubes.
Maybe not allways the best, but hey, they do wat they are supposed to do and that's enough for me, the musicshop and the musician.
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