Hi all...
I am building a clone of the Fender Deluxe reverb for a friend. He bought a kit with everything from cabinet to the smallest screws.
It is done and working nicely except from the vibrato.
It is tube V5, a 12AX7, but it does not conduct properly. Both cathodes shows 0V. This the tube that involves the vibrato circuit with the optocoupler.
On the "bulb side" of this optocoupler the voltages read near some 380-400V which I believe is too much. Together with the 0V on the cathodes my guess is that something is wrong
I have changed the tube three times with all brand new tubes so I am guessing that the tube is not the problem. I have also desoldered everything a couple of times. Strangely enough when I desolder the cable to the negative bias circuit I get some voltages on the cathodes of the V5.
So... I am suspecting the optocoupler to be the culprit, but the it is also brand new and I hope that I don't have to get another one?
Any Ideas?
ps. I could not upload the schematic
Best regards
/John
I am building a clone of the Fender Deluxe reverb for a friend. He bought a kit with everything from cabinet to the smallest screws.
It is done and working nicely except from the vibrato.
It is tube V5, a 12AX7, but it does not conduct properly. Both cathodes shows 0V. This the tube that involves the vibrato circuit with the optocoupler.
On the "bulb side" of this optocoupler the voltages read near some 380-400V which I believe is too much. Together with the 0V on the cathodes my guess is that something is wrong
I have changed the tube three times with all brand new tubes so I am guessing that the tube is not the problem. I have also desoldered everything a couple of times. Strangely enough when I desolder the cable to the negative bias circuit I get some voltages on the cathodes of the V5.
So... I am suspecting the optocoupler to be the culprit, but the it is also brand new and I hope that I don't have to get another one?
Any Ideas?
ps. I could not upload the schematic
Best regards
/John