The Fine Things are Always Hand Made
I discovered something today that I had never noticed before. Background - I am working on an FM Phantom which has the later Jones plug connector. I just made a crossover cable with a female Jones plug to a standard Scott round plug to test the tuner with a "standard" amp. I was double checking my new connector and saw the 6.3v filament line on the amp I was working with (my working set in the Stratford cabinet), had the CT grounded. The Jones plug amp with the FM Phantom was grounded on one side, NOT via the CT. The Phantom Deluxe schematic shows one side of the filament to ground.
I happen to have 5 Phantom Deluxe amps here at the moment, so I spot checked. The Jones plug amp is end ground. Two of the round plug amps are center grounded. The other two round plug amps are end grounded, and the CT lead on the transformer has never been soldered.
This implies that Phantom Deluxe amps are not readily interchangeable between sets. Scott always seemed to make things fairly fool-proof, but this would be a difficult to spot issue. Has anyone else noticed this? How are your Phantom Deluxe amps wired?