Discussion in 'Amateur Radio Amplifiers' started by KJ4AQU, Apr 16, 2012.
On the CW/Tune position there is less ZSAC. Does less ZSAC give less distortion?
It was always my understanding that the linear curve of the amp was the same when switched from cw to ssb since the ZSAC changed as the Plate voltage increased keeping the amp still within the linear portion of the curve. Thus, the IMD should still be very good and distortion not a problem.
A pair of 3-500Zs is reasonably linear when the ZSAC is >140mA. On the CW/TUNE position ZSAC is c. 120mA due to the decrease in PS V.
The AL 80 A or B is a good choice. Solid amp that can easily be run on your 110VAC circuit.
Its actually a bit better Lou.
The AL-80A is a bit problematic but the Amp Supply LK-450 is built like a rock, just stay away from the no tune versions.
Just appeared on eBay, the Henry 1KD-5 HF amplifier (California seller) Item # 230781080358
This Henry amp used one 3-500Z tube, this may be what you are looking for.
With 120vac/240vac input a stock 1KD-5 has 5.95v on it's 5v filament. This level of fil-V reduces emissive life to about 2% of normal so a new 3-500Z may be needed.