Right out of a WWII B-29
Yet another oddity. was that someone, Phasemaster? (No, P&H) marketed a "linear amplifer" for awhile using modified 1625 tubes. I built one out of an ARC-5 by adding a 3rd socket, the rest of the tx was already gutted. What you did was, the 1625 had an extra, unused pin over the 807. IF you were lucky and got the "correct" brand of tubes, the cathode and beam forming plates wire came out separate from the tube seal. You could grind a hole in the tube base, unsolder the two wires in the cathode pin, identify the suppressor/ beam forming plate lead, and move it to the unused tube pin
Now you can create a cathode driven amp with all the grids grounded. I used it on CW. I grew up "in the country" and most the neighbors were at least 1/4 mi away, 'xcept for across the street I'm sure it was "dirty."
P&H 1625 amp:
A 200 watt grounded-grid linear amplifier
Note that they used an ARC-5 loading coil LOLOL
Yet another oddity. was that someone, Phasemaster? (No, P&H) marketed a "linear amplifer" for awhile using modified 1625 tubes. I built one out of an ARC-5 by adding a 3rd socket, the rest of the tx was already gutted. What you did was, the 1625 had an extra, unused pin over the 807. IF you were lucky and got the "correct" brand of tubes, the cathode and beam forming plates wire came out separate from the tube seal. You could grind a hole in the tube base, unsolder the two wires in the cathode pin, identify the suppressor/ beam forming plate lead, and move it to the unused tube pin
Now you can create a cathode driven amp with all the grids grounded. I used it on CW. I grew up "in the country" and most the neighbors were at least 1/4 mi away, 'xcept for across the street I'm sure it was "dirty."
P&H 1625 amp:
A 200 watt grounded-grid linear amplifier
Note that they used an ARC-5 loading coil LOLOL