[MRCA] T-19 Transmitter

[Ray Fantini]

Ok, so I am building up this new transmitter for use at Dayton that will be driven by a Narco T-12MP power supply modulator. The narco box will do all the T/R switching and modulation functions so am assuming that I won't need any relays in the T-19 transmitter that I am using being B+ and HV will only be available when the narco sends it to the T-19. All of the T-19 hulks that I scrounged up were missing the crystals, magic eve tubes and most of the other parts and were all striped of most of the internal components so been doing a lot of work to try to get them back to what may have been the original type of circuit.
Attached is a Jpeg of what I am intending to build on the T-19 chassis that's using the original design less the crystal stuff and all the internal relays but they are long gone anyway. What the hell did people do with all the crystals that were in these transmitter anyway?
The big questions would be if R90 the screen dropping resistor should remain or be bypassed? If there would be any advantage to going with just one 1625 as opposed to two? I also have a clean +330 volt feed before the modulation transformer from the narco and can maybe use that for the screen grid supply, but keeping in mind that the modulator is only good for about five watts of modulation don't need a bunch of RF carrier power.
If I get the new plug in for the narco today and get the rest of the transmitter back together hope to have this up and running this weekend. Being that the output will not be coaxial thinking of just using different size incandescent light bulbs for the dummy load, somehow recall that if the roller inductor is set to 0 that the natural inductance of the output tank was around 50 Ohms but may be mistaken. Know one thing for certain that when its used in the field the antenna will be way short and hope the internal inductor will do the trick.

Ray F/KA3EKH
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