>The SCR-274-N and ATA transmitters mentioned in this thread use PA screen modulation, not plate, in the military systems. Only the AN/ARC-5 transmitters are plate and screen modulated. >Mike / KK5FI didn’t know that. What modulator do they use? The only mod unit I’m familiar with is the MD-7 and it is plate/screen.-CharlesWB3JOK/0