Icom PW-1 1kw Linear Amplifier
This is a fantastic amplifier that when coupled with the Icom 746/756/756PRO produces, in effect, a 1kw output transceiver. Band changes, tuning, and selection of one of 4 antennas is completely automatic.
On September 18, 1999 I received my new Icom PW-1 amplifier. I had it shipped to St. Louis although the intention is to install it at the Taos location. It seemed like a good idea to set it up first in civilization and then move it to Taos.
I purchased the amp from Ham Radio Outlet. They've done a good job for me in the past. The price was competitive and it shipped from stock.
Although the amp only weighs 55 pounds -- the packaging is substantial and the total weight of the parcel was 73 pounds.
We unpacked it and discovered that Icom had not provided strong enough packing. The fitted Styrofoam pieces had broken apart in shipping. The amplifier appeared undamaged. The instruction manual was consulted and I chose to remove the control panel from the amp and make it remote. This took about 25 minutes, but was relatively simple. All necessary cabling to remote the control panel is included. The 10/12 meter modification was reviewed. It involves removing one diode from the main control board. The diode is a surface mount device and about the size of a ballpoint pen tip. Since this would involve soldering and potentially screwing up the board, it was decided to test the amplifier before performing the modification.
We didn't have 220 at the St. Louis location at that time, so a 110 volt plug was fitted and the amplifier connected to the IC756 and the vertical. This was simple to accomplish since the amp comes with enough cabling to locate the amp up to ten feet or so from the exciter.
The programming instructions are simple and the amp was soon tracking bands with the 756. The ALC setup produced almost exactly 500 watts out, which is all the amp is supposed to produce on a 110 volt supply.
Everything was turned off and the diode removed. The amp checked out fine on 10/12 meters. In fact, amplifier efficiency seems higher on 10 and 12 than on the lower bands. I did not test the amp on 6 meters as my antenna can only take about 200 watts on that band.
The amp is very quiet. In fact, the entire operation was remarkably simple. Nothing like the old dual 3-500Z amp we used to use at WØQEV (Washington University ARC).
The amp has now been installed at the house in Taos, where 220 was available. Installation took about 20 minutes, including the time to solder an additional 1/8 inch phone jack on the remote control cable already in use with the IC756 and the computer.
Performance has been excellent and a full weekend running 1kw on RTTY in the BARTG test produced no surprises except to note that it is a lot easier to get a "run" going with 1kw than with 100 watts.
In fact, I purchased a second PW-1 to use in St. Louis -- and brought 220 up to the shack.