Finally built a good dummy 50 ohm load with shielded test leads for my scope. Verified the yet unopened TRC 433 (good receiver side) put out a constant 3.99 watts, with 40 volts peak to peak accross the load (no modulation), and very nice modulation waveform (used a wavetek 180 audio oscillator for mike drive at 1000 Hz between .03 and 1.3 volts), and confirmed modulation pretty much constant at 95%. At 100%, too many harmonics. This looked at with a vintage HP 8556 (not 8566!) spectrum analyzer.
On the much tweaked and unmodifed 458, verified 42 volts peak to peak on unmodulated AM carrier, and 70 volts peak to peak across the load in SSB, which works out to 12.24 watts for SSB and 4.2 watts for AM.
The 458 power supply runs hotter than that on the 433 (different design).
Then set up the 433 with a 1000 Hz test signal into a load in the basement and moved the 458 upstairs and connected the outside dipole to tweak the receive side one more time, on channel 15. Had the 458 RF gain at max and mid level S units, although it was only 30 feet away from the 433 in the basement. Used an ac voltmeter across the 458 speaker leads, which is more accurate (and per the manual) than using the S meter on receive, which can also be done for a quick job in a pinch.
On the much tweaked and unmodifed 458, verified 42 volts peak to peak on unmodulated AM carrier, and 70 volts peak to peak across the load in SSB, which works out to 12.24 watts for SSB and 4.2 watts for AM.
The 458 power supply runs hotter than that on the 433 (different design).
Then set up the 433 with a 1000 Hz test signal into a load in the basement and moved the 458 upstairs and connected the outside dipole to tweak the receive side one more time, on channel 15. Had the 458 RF gain at max and mid level S units, although it was only 30 feet away from the 433 in the basement. Used an ac voltmeter across the 458 speaker leads, which is more accurate (and per the manual) than using the S meter on receive, which can also be done for a quick job in a pinch.
