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The following station and antenna pics were from a presentation by Kim – N5OP given during the Fall 2020 Virtual Zoom OKDXA Meeting.

Antennas get a bit droopy with an ice load but SO FAR(!) they’ve survived three significant storms.


My brief amateur radio bio.


Custom design log construction on 10 ac lot; all control and transmission lines exit and enter under the slab.


Force 12 Sigma 80 — off-center fed vertical dipole.


Array Solutions K9AY receive loops switchable to favor NE-NW-SW-SE. Not as good as Beverages, but I didn’t run transmission lines for Beverages because of concerns about antenna-deer encounters and because much of the open field is hayed by a neighbor. In hindsight, Beverages could have been run through the woods.


HDBX-48 tower, 8 ft of chrome-moly steel mast extending from top from a HyGain T2X rotor, all supporting a (top to bottom) discone for 100 MHz – 1 GHz, KLM-KT34A Tribander, Arrow antennas corner reflector for 2m-70 cm FM, CushCraft DW3 for 12-17-30 m, and a CushCraft 40CD2 for 40 m. Also seen is a shunt-feed for 160 m, a Davis Instruments Integrated Sensor System pod for weather instruments at 30 ft, and a 75 m inverted V suspended at the 40 ft level.


A better perspective to see the antenna spacing. The 40 m and DW3 dipole is offset 90 deg from the tribander to minimize any interactions.


The large gray box holds a home-brewed L-network with a 24 VDC reversible motor drive on a vacuum variable capacitor. The bottom of the shunt extends off of the PVC arm. 1:1 match range is 1800 kHz through about 1950 kHz.



Operating position. Bottom L to R: World Radio Labs Globe Champion 350 transmitter (~165 W output AM/CW), Hammarlund HQ-170 receiver, TenTec Orion II transceiver with RX-366 subreceiver, Kenwood TS-930SAT with Phoenix Contact Quint 28 V 20 A CCS industrial SMPS power supply and CompuDigital regulator board.

Top L to R: HP 5382A 225 MHz frequency counter for boat anchor transmitter, Kenwood KC-10 clock, B&W 334A 1 kW dummy load, Timewave DSP-59+ audio DSP for Kenwood TS-930S and HQ-170 atop SP-930 external speaker, LP-100 Digital Vector RF wattmeter atop the Ameritron AL-1200 amplifier with mod for 4 kV B+, homebrew VHF/UHF remote coax switch for discone and corner reflector sitting atop Heathkit HD-1481 remote coax switch, which is atop Green Heron RT-21 rotator controller, controller for K9AY receive loops, sitting atop LDG DTS-4 antenna switch, which is sitting on an Ameritron ATR-15 antenna tuner.

On the desktop is a Bencher straight key, a Vibroplex Presentation “bug”, and MC-60 mic (for AM ‘phone). On the glass top is KC-1 “Kansas City” keyer, a set of Bencher paddles, and a Heil switchable double-element (HC-4 and HC-5) mic for the Orion II. The TS-930s uses a Shure 404B hand mic (an early version of the Shure 444).



The Globe Champion 350 has solid state rectifiers (replacing a pair mercury vapor 366A/argon gas 3B28s), solid state 5U4A high vacuum rectifier, a modified VFO for high stability. The PA tubes were a pair very rare and expensive AX9909 power pentodes. These were replaced with Motorola 8643 power tetrodes which are now plentiful and cheap (I have 4 pairs of replacements) and much more rugged than the original AX9909s. The transmitter has also been modified with a 2:1 output transformer such that it will feed a 50 ohm load on 160 m. This mod also made for easier tuning on all the other bands. These mods were published as an article in the August 2016 Electric Radio magazine. These radios were among the best of their day.

Save for solid state rectifier replacement, the HQ-170 is essentially stock. The transmitter and receiver were very high-end radios for the day, purchased new by W5JHJ in 1959, and were the first radios I ever used as a ham.



TenTec Orion II on the left, Kenwood TS-930S on the right. The Orion II was among the top rigs of its day in 2007. The main receiver has 300 Hz, 600 Hz, 1 kHz, 1.8 kHz, 2.4 kHz, 6 kHz, and 20 kHz roofing filters in the 9 MHz 1st IF (all is DSP after the 1st IF) and the RX-366 subreceiver (derived directly from the TenTec Eagle receiver) has 600 Hz, 2.4 kHz and 6 kHz 1st IF roofing filters (all DSP after the 1st IF).

The TS-930S has the International Radio 400 Hz, 2.4 kHz and 6 kHz IF crystal filters (2nd and 3rd IF) and an International Radio 6 kHz crystal roofing filter in the 1st (40 MHz) IF. The PA has been modified for the 2SC1699 12 V driver transistors, replacing the original Motorola MRF-485 “low F_e” 28 V drivers, which were marginal in 28 V service. A K1EA WinKeyer is barely visible sitting on top of the TS-930S. A Heathkit Cantenna is under the righthand side of the desk for brief duty at power kevels up to 2 kW.


73 and CU in the pileups!