I've been working continuously for more than fifteen years at seeing how much competitive contest performance I could squeeze out of a station, deliberately limited to 100W CW and simple antennas, on 1 1/3 acre of forested property. I limited myself to 100W because I didn't want the hassle of handling QRO RFI and I didn't think I needed it to have fun with CW, and simple antennas because of the difficulty of keeping the expensive ones working in our climate. I wanted also to be able to service my own antennas. It's working well. I can win stuff with this station (especially if I am careful to select obscure DX contests in which I have only casual NA competition!). This is a fun station to operate because it demands constant attention from the operator to extract best performance from the radio and the antennas. My goal is to maintain some decent level of profficiency in CW and operator skills, and in hands-on operating of a modern HF radio. I do that through contesting with this system.
This is an Elecraft-centred station, arrived at through an evolution that included a couple of K2s and a PRO III, the latter of which I had bought mostly to see what the fuss about big radios was all about and because there was no K3 then. I ordered my K3 with 100% down payment in the middle of the FL QSO Party the day it was released, and snagged the first Canadian sale with #95.The station is designed to capitalize on the capability of a fully-loaded K3.
I like hands-on contesting so I run completely unassisted and I found that computer rig-keying took all the fun out of the process and pushing buttons seemed too, I dunno, impersonnal?, so it's gone too. Support software is limited to N1MM and Logger32 and the two Elecraft Utilities (K3 and P3). I use a CMOS-4 external keyer just because I like it and I'm used to it. It is an easy station to keep working. It is also designed for quick pack-up for field usein that everything is easily accessible.
The system includes a 145 AH battery back-up system including some A.C. for running the logging computer and monitors, and emergency lighting. The battery is maintained with a POWERgate PG40S and battery condition is constantly monitored using PowerPROview and displayed on one of the two station monitors . The system is designed to seamlessly handle loss of power from the mains long enough to gracefully save logs and exit programs. After that, non-essential loads can be shed by a single switch and the station can run QRP with minimum battery drain. I've never used this back-up system in anger but, having spent my entire life around airplanes, this design just makes me feel better. And it is EMO-friendly since the station also includes V/UHF with back-up antennas and dedicated radios and modems, all connected to the emergency DC buss
There are two primary wire antennas: a full-size 160M delta loop with the apex at 95 feet, fed at one corner. Within days, I will be able to reverse the feed point from the station at will such that I am effectively flipping the radiation pattern for this loop. I hoping for additional coverage since it is not a true delta loop and EZNEC patterns show something very non-traditional and unsymetrical. It also has some wicked lobes when operated on the higher bands that might prove beneficial if swung around 180 degrees.There is also an 80M dipole at 75 feet . Both dipoles are fed with ladder line and used multi-band, and that includes 6M. The SWRs I see on those antennas are well within what the K3 can match. The worst SWR is 5:1; usually it is closer to 3:1. There is insignificant transmission line loss in any case. I can select either antenna to eitherRF input of the K3, which has the second receiver and a full suite of filters to match the main RX. That selection is assisted by a couple of MFJ-949Es used externally for their switches and the baluns. One of the two MFJ 4:1 baluns has been swapped out for a 9:1 Guanella.
In addition there are two vertical antennas. One is a 32-feet vertical with 5,000 feet of radials, matched by a remote antenna tuner. The other, only a week since it was commissioned, is the 95-foot tower from which the 160M delta loop has always hung. With VE1ZAC and an AIM 4170, we found that replacement of the tower steel guy cables by Phillystran earlier this summer, coupled with some tricks with relays to open up the 160M wire delta loop, this tower wold load directly with 50 Ohm coax with minimum loss as a 1/4 wave vertical with no interaction with the 160M delta loop. The new vertical repeatedly show significant promise on top band and its pattern fills in some existing holes on 80M and 40M. It is a one-wavelength vertical on 30M and it is now my best antenna on this band. The same as for the wires, these antenna ouputs can be routed to either K3 RF input. The tower vertical has a 3,000-foot radial field.
For listening antennas there is a 500-feet reversible Beverage (DXE), a K9AY (Array Solutions), and a home-brew shielded loop based on the design by N6RK (see NCJ) which is built but remains untested. A new control box is finished. I now able to select any one of three listening antennas to either RX antenna input of the K3's two receivers and play with diversity receive with antennas of differing characteristics. All my experiments with listening antennas point to the same conclusions: this contest station cannot live without them; and, having more than one listening antenna and two receivers is the height of luxury.
The latest addition to my station is an Elecraft P3 panadapter (Serno #7). See eHAM Reviews for my first contesting experience with that station accessory. Prior to that I had an early N8LP LP-PAN, a system which taught me a lot while I implemented it but today I prefer the simplicity of plug-and-play. With the P3 now in place and exceeding my expectations, I have declared the station complete so far as design and equipment go. By next week I will have changed my mind.
1783742 Last modified: 2015-03-14 23:17:50, 6173 bytes
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