[Icom] Icom Pro II and PW-1 (Do I have a problem here!)

Thu, 27 Jun 2002 13:30:29 +0200

Hi Adam

Better ask stupid then burn of the linear :-)

So here it come, I have the IC-4KL it works on 220V
How can I adjust the setup so that no matter how the Pwr control knob on my
IC-746 is set, it will not put more than 600 Watt out ?

Tnx in advance

Per OZ1EQC
IC-746, IC-4KL, SOMMER XP-508 (just ordered the XP-808)
   Member of: EDR, ARRL, HSC
            [email protected]
      www.bekker-madsen.dk

----- Original Message -----
From: "Adam Farson" <[email protected]>
To: <[email protected]>
Sent: Thursday, June 27, 2002 1:19 PM
Subject: RE: [Icom] Icom Pro II and PW-1 (Do I have a problem here!)

> Hi Bill,
>
> The ALC in the PW-1 will hold the exciter output at the level required to
> drive the amplifier to the preset power output. If the PW-1 requires 80W
of
> drive to produce 1kW output. turning the transceiver's RF POWER control up
> to full output will make no difference, as tithe ALC line is regulating
the
> drive level.
>
> As the ALC is the amplifier's first line of defence, it is absolutely
> mandatory to set it up correctly. Assuming that your Bird power meter is
> accurate to within 5%,another method is to adjust the ALC for a reading of
1
> kW (into a dummy load!)
>
> Best 73,
> Adam, VA7OJ/AB4OJ
> North Vancouver, BC, Canada
> http://www.qsl.net/ab4oj/
> Note new e-mail address:
> mailto:[email protected]
>
>
> -----Original Message-----
> From: [email protected] [mailto:[email protected]]On
> Behalf Of Bill Tarkington
> Sent: June 26, 2002 21:07
> To: [email protected]
> Subject: [Icom] Icom Pro II and PW-1 (Do I have a problem here!)
>
>
> Having recently purchased a Pro II, I followed the owner manual
instructions
> for both the amp and radio to set the ALC level on the amp so as not to
> overdrive it and risk FET damage.  Once all proper connections are made,
> book says to adjust the exciter (Pro II) output to 100W, then turn ALC
> adjustment screw clockwise slowly while key down on either CW/RTTY and at
> same time reading the ALC scale on the PW-1 control head until meter
needle
> is dead on the ALC adjust mark. Once adjusted thusly, key down at 100W
from
> the exciter and check PW-1 power meter to insure 1KW output.  Did all this
> and all looked to be okay.  HOWEVER, I noted that the RF power knob on the
> ProII was not fully clockwise (wide open).  Advancing it to full open
seemed
> to indicate the Pro  II was putting a little something in excess of 100W
per
> its power meter.  Bottom line is, I do not know what meters to trust here.
> Out of curiosity, got out the Bird 43 Watt meter with 1000W slug therein
and
> did some checking. First used the Bird meter with 100W slug to set
barefoot
> output on the ProII at precisely 100W and left it there(  little less than
> full open). Further testing with the Bird in and out of the circuit with
the
> PW-1 output seems to indicated the Pro's watt meter is pretty accurate,
but
> the power meter on the PW-1 is reading low.  If do the ALC adjustment
using
> the PW-1 power and alc meters per book,Bird says full amp output is 860W,
> not 1KW the PW-1 watt meter indicates. If do the ALC adjustment using just
> the Bird meters readings while ignoring the PW-1, the ALC goes into the
red
> some little way, and the output per the Bird is about 1250W.  All this
> leaves me wondering which watt meter to trust to obtain the full 1KW
output
> of the amp. If use the Bird and guess wrong, will 1250W out with ALC being
a
> little in the red likely cause me some amp damage?  The safe thing to do,
of
> course, is go with the PW-1.. BUT, I want them to agree more or less with
> one another or understand why not.  Incidentally, if it matters, all tests
> were done into a  1500W dummy load.  Am I missing something here?
Comments
> please. Bill, K3YC
>
> ----
> Your Moderator: Dick Flanagan W6OLD, [email protected]
> Icom FAQ: http://www.qsl.net/icom/
>
>
> ----
> Your Moderator: Dick Flanagan W6OLD, [email protected]
> Icom FAQ: http://www.qsl.net/icom/
>