>Ron - W4WA
>Alpha made its entry in the amplifier market in 1970. The amplifiers were
>PA-70A - Used a 3CX1000A7 - Air Cooled. I still have serial number 5.
>PA-70V - Used a 3CV1000A7 - Vapor cooled tube - Had a distilled water
>Alpha 77D - First amp. to use an 8877. Same cabinet as the PA-70 series.
>Alpha 77DX - Redesigned and larger cabinet styling. Single 8877. More room
>Alpha 77SX - Same cabinet styling as 77DX but used (2) - 8877's I still
Did you correct the tank circuit Z problem? If so, please describe how.
>All the amps used an RF drive bias switching circuit wjhich had design
... amen, Bob. IMO, it is not good engineering practice to allow the T/R
bias to switch to non-linear mode during transmit, which is what every RF
bias switching scheem does during SSB mode. It makes better engineering
sense to make the T/R bias switch in unison with the T/R (RF) relays.
R. L. Measures, 805-386-3734, AG6K
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