On Fri, 06 Jun 1997 10:36:03 EDT, km1h@juno.com wrote:
>I guess the question I have is why anyone would wish to give up a bullet
>proof workhorse amp such as the AL-1200 for something completely unknown
>with no track record such as the QRO?
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"Bullet proof" is in the eye of the beholder I suppose, but my
experience would rate it a bit more tender than that.
The AL-1200 is probably fine for CW/SSB operation, but running it at
full power on RTTY will overheat the tank coils on 80 and 160 meters.
There is nothing in the manual to caution you against this. During a
recent contest, mine got hot enough to melt the solder connecting the
80 meter tap. The plastic support rods also melted and the coil
twisted itself into a pretty good slinky imitation. It needs more
cooling air in the tank area. Cost about $25 for a replacement coil.
Also, the step-start circuit is not slow enough in my opinion. With
the original factory circuit, the delay is only a fraction of a second
and one can observe a major arc when the relay closes. I tore the
whole circuit out and installed a real time-delay relay set for about
three seconds and now it's much better behaved. I can't imagine the
original step start relay lasting very long at all. You'd have to see
that arc to believe it. It was brutal.
The power supply does seem to be well designed and constructed,
though. When the unit was about 8 months old, the tube developed an
anode to grid short with the accompanying flash and bang, but there
was no damage to the power supply or meters at all. Ameritron
replaced the tube with no questions asked and the replacement has been
running for about a year now with no problems.
It's a pretty good amp, but "bullet proof"....? I don't think so.
73, Bill W7TI
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