[Icom] PW1 ?

Thu, 26 Jun 2003 11:08:04 -0700

Hi Ken,

For personal reasons (largely driven by a near-fatal encounter with a
4CW10000A in 1968) I have always used solid-state amplifiers. I now have a
Yaesu Quadra, driven by an IC-756Pro2. Even though I have never owned a PW1,
it uses the same power devices (8 X MRF150) as the Quadra, and is in the
same power class. The Quadra may be an option for you as well. I have posted
a lot of information about it on my website. Most of the automated features
on the Quadra carry over when using an Icom exciter.

The Quadra has one important safety feature lacking in the PW1; a
reflectometer at the autotuner output places the amplifier in standby when
it detects load SWR > 3:1. This prevents damage to the PA stage, output
filters or tuner in the event of an antenna system failure. Also, the Quadra
offers a load analyser display (SWR at autotuner output and input vs.
frequency) and easy 10/12m enabling (via programming). On the other hand,
the Quadra does not dynamically track frequency changes within a band, but
requires that the operator initiate a band-change or tuning cycle by
pressing a front-panel key.

You can download the PW1 service manual, and other related documents, on
http://www.qsl.net/icom/

As for IMD3, typical values for the PW1 and Quadra at 1kW PEP 2-tone are
around -32 dBc (0 dBc = composite PEP of two equal tones). I measured -33
dBc at 1kW PEP output on 14 MHz with my Quadra. By comparison, the ARRL Lab
test suite (QST, 5/2000) yielded -37 dBc for the Acom 2000A at 1.5kW PEP
output on 14 MHz.

There are links to articles on tube and solid-state amplifier design
philosophy on my homepage.

1kW vs. 1.5kW? That's 1.5 dB, or 1/4 S-unit....

Best 73,
Adam, VA7OJ/AB4OJ
North Vancouver, BC, Canada
http://www.qsl.net/ab4oj/
Icom FAQ Site:
http://www.qsl.net/icom/

-----Original Message-----
From: [email protected] [mailto:[email protected]]On
Behalf Of Ken Kinyon - W7TS
Sent: Wednesday, June 25, 2003 22:55
To: [email protected]
Subject: [Icom] PW1 ?

I am seriously considering replacing my Ten-Tec Titan with a IC-PW1.
I would appreciate any input.  Does anyone think I  will miss the extra 500
watts?
Regards,
Ken W7TS.
ps the rig driving it will be ProII

-------------------
Kenneth E.  Kinyon
34 Princeton Circle
Longmont, CO 80503-2106
Voice: (303) 684-0037
Fax:  (303) 776-5088
E-mail: [email protected]
	  [email protected]
	  [email protected]
ALPCA #8339
ARRL-LM
-------------------

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