[ICOM] ALC questions.

[paul at w8aef.com]

Ham's that insist on using an analog watt meter to measure their ssb output 
power will ALWAYS have power problems.

Doesn't matter who makes the meter either.

A good oscilloscope in the RF line will show you exactly what your ssb PEP 
output is, and you can compare that peak-to-peak output directly to the 
continuous carrier peak-to-peak output.

de Paul, W8AEF

----- Original Message ----- 
From: "Bob Marzari" <w3pt at comcast.net>
To: "Ic756pro3" <ic756pro3 at yahoogroups.com>; "Icom" <icom at mailman.qth.net>
Sent: Monday, April 17, 2006 4:09 PM
Subject: [ICOM] ALC questions.


> Sent this to the PW-1 list but have seen no action. Let me try it here.
>
>
>
>
> To: ic-PW1
> Subject: ALC questions.
>
>
> Amp NOT making full power in SSB mode measured with a Bird Model-43 
> Thruline
> with the 4300-400 PEAK capability. All the following are into a quality 50
> ohm load.
>
> Lets start with the PRO-3. It makes a full 100W in SSB with a sustained
> fiveeeee or a whistle. It's ALC reads to the proper level, the end of the
> orange marker.
>
> Turn on the amplifier and repeat the above test and all you can get out of
> the amp is 500 watts. The PRO-3 will only make 60 watts and it's ALC 
> reading
> is still at the right end of the orange marker. The ALC on the AMP barely
> makes it to 1/4 scale in this condition.
>
> My amplifier will make 1KW out in RTTY and CW and the ALC sits right at 
> the
> limit line.
>
> Maybe I should set the ALC on the amp with an audio tone into the mic
> circuit and then be careful to turn the power back in RTTY and CW? Should
> not have to do this.
>
> Any one else run into this????
>
> Bob, W3PT
>