[Icom] PW1 vs 4KL

Wed, 02 Jul 2003 23:38:45 -0700

Hi Malcolm,

The only minor concern you might run into with the IC-4KL is that the
2SC2652 BJT power devices used in its PA stage (and in that of the IC-2KL)
are discontinued. All is not lost, though - the MRF448 is a close cross, and
is available from RF Parts.

As Harry WE1X remarked, the 4KL PSU is no longer manufactured. I have not
heard of any massive power-supply failures, so this may not be a serious
worry. I ran an IC-32KL in my station for 10 years, and finally replaced it
with a Yaesu Quadra at the end of 1998. Both amplifiers have given me
flawless service. At the time I bought the Quadra, that amplifier already an
excellent service record, whilst the PW1 Ver. 1 was still encountering
teething troubles. Today, I would be comfortable purchasing the PW1 Ver. 2.

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/

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 Malcolm Ringel
Sent: Wednesday, July 02, 2003 15:52
To: [email protected]
Subject: [Icom] PW1 vs 4KL

I am running a 756PROII and have narrowed my amp choices to a 4KL or a PW1.
The 4KL would obviously be used and I think the PW1 (version 2) would also
be used, so the warranty issue would not be a factor.
That said, I would appreciate hearing from those who have had/used either or
(even better) used both of these amplifiers.
Are parts/repair a significant problem yet for the 4KL ??
As always, thanks in advance for any assistance any of you good folks can
provide.
73, Malcolm, K3KZ, Saint Michaels, MD