[Amps] plexiglas isolation in coils

[Tom W8JI]

> I can confirm it is more than "apparently". I owned an 
> AL-1200 which
> twice had the plastic coil supports let go while running 
> at full
> power, once on 80 meters and once on 160 meters, both 
> RTTY.
>
> I sold the rig to a non-RTTY op and as far as I know he is 
> happy with
> it.

The AL12 series bower was downsized after the first six 
months of production because no one wanted a high speed 
blower. On SSB and CW the change wasn't an issue.

If people read the manual, which few do, they would see a 
higher speed blower is available or as an option the inlet 
could be pressurized with a booster fan.

We use an AL1200 in 160 CW contests and with two rigs (there 
is a voting system that allows only one TX at a time to 
transmit) the amp runs virtually continuously on CW. There 
isn't an issue if the manual is followed. Mine uses the 
stock blower set on high speed and has a booster fan on the 
inlet.

What critics (especially those who never have built a 
commercial product or been in any type of amateur radio 
manufacturing) is amplifier noise is a much bigger issue 
than RTTY operation, so the compromise is set according to 
end use. The amateur market is entirely different than a 
commercial market, both in margins and what users expect.

It's pretty easy to pick apart any product that is design 
driven to meet a certain market.

73 Tom