04-03-2013, 11:20 PM
Paul
Don't know, the tubes are identical, but 12J5 may need the shield grounded and I think the respective pin for 12J5GT is NC.
Try to ground it, see if it helps.
Also I wonder if you may have had some problem even with glass tube where the radio does not really work correctly and plays because a tube may act asn an antenna. But when you introduce a metal tube the antenna effect stops, and what is supposed to work as the antenna amp does not really get anything from the real antenna.
Things like open coils do that.
Don't know, the tubes are identical, but 12J5 may need the shield grounded and I think the respective pin for 12J5GT is NC.
Try to ground it, see if it helps.
Also I wonder if you may have had some problem even with glass tube where the radio does not really work correctly and plays because a tube may act asn an antenna. But when you introduce a metal tube the antenna effect stops, and what is supposed to work as the antenna amp does not really get anything from the real antenna.
Things like open coils do that.
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