>
>Just spent quite a bit of time looking over the past 3 years of
>archives on the AL-1200
>
>They indicate:
>1)40/80 RTTY operation at near full power burns up tank circuit
>components
There is not enough copper in the tank. There is apparently no air
cooling for the tank. Both problems can be fixed.
>2)10 meter efficiency is poor with little chance of getting full
>output.
At best, you might be able to get 2db more suds on 10m/11m by using
larger tank conductors. Could anybody really tell the difference?
Doubtful.
>3)Parasitic oscillation problems haven't been solved
The good news is that 3cx1200A7s almost never have filament/grid shorts.
The 3CX1200Z7 is a more stable design since it has approx. 10% as much
feedback C. MFJ has not switched to the improved version. Is Martin F.
Jue clueless?
>4)Noise from fan intolerably loud
>5)WARC bands are a compromise because of tuned input circuitry. One
>has to mistune it to get both WARC and adjacient non-WARC bands.
>
>Is this info still valid?
You forgot the prob. with the 1000pF HV ''bypass''. -88-ohms of Xc is
assuredly not a ''bypass''.
>If it is, it says manufacturer's apparently
>never test their
>products. I don't understand why anybody would buy this unit.
>
>There doesn't appear to be any currently made amp out there that is
>instant on, quiet, stable, WARC band friendly with 1.5CCS output
>
>Brian/K3KO
>
? 1500w out CCS requires a 2500w CCS supply. The Henry 3K-A is the only
game in town. However, the VHF stability needs improving, it needs
glitch protection, and it needs high speed switching.
cheers
- Rich..., 805.386.3734, www.vcnet.com/measures.
end
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