OH2GVB Station Equipment

I became a radio amateur in 2005. My first and still only HF transceiver is the Yaesu FT-897D. It offered the bands and modes I would likely be using for the foreseeable future, and has sufficient power output. Also, it is a very convenient portable rig, especially with internal batteries installed. I originally had Yaesu's FNB-78 NiMH-battery packs, but I've since replaced them with a homebrew lithium battery pack that offers much better performance. All my antennas are homebrew—I'm not about to design and build my own transceiver, but a technical hobby should always involve some hands-on work. Antennas are simple enough. I've used a fishing pole vertical and a vertical dipole, tuned with the antenna tuner (despite the obvious losses), now I have a home-made HF9V-clone. For portable use, I've made a trap dipole for 80 / 40 / 20 / 15 / 10 meters and the occasional monoband dipole. On VHF and UHF I use a pair of Quadrifilar Helical Antennas. I'm now using them with a Kenwood TM-V71E, and I also have a couple of cheap Chinese dualband handhelds, which offer excellent value for their price. I've also built a small, portable VHF/UHF Yagi out of a fishing rod, to increase the range of the handhelds.

Yaesu FT-897D
  • HF / VHF / UHF, 100 / 50 / 20 W, all-mode transceiver
  • With Inrad 2.0 kHz SSB filter
  • Homebrew external power/signal meter
  • Originally I had Yaesu's internal FNB-78 NiMH batteries in it
  • Then I installed custom lithium-polymer batteries which were fantastic to use, but short-lived
  • Now I have an external NiMH battery pack using low self-discharge NiMH D-cells
  • When I still used the internal FNB-78 NiMH batteries, I built this homebrew discharge circuit to condition them
Kenwood TM-V71E
  • VHF / UHF, 50 W FM transceiver
  • Wide-band FM receive (+air band AM), covers also 23 cm
  • Dual receive V/V, V/U, U/U
  • Simultaneous transmission and reception V/U, U/V
MFJ 941E Versatuner II
  • Manual HF antenna tuner
  • 300 W power capability
  • Dual-needle forward/reflected power meter with 30 / 300 W ranges (its backlight has been replaced by a white LED)
  • Three coax lines and one balanced line output, tuned or bypassed
  • With custom TX-request switch, requests a low-power carrier from the radio for tuning (interfaces to radio's ACC connector)
LDG Z-100Plus Autotuner
  • Automatic HF antenna tuner for portable use
  • 125 W power capability
  • Custom modified for low TX-power tuning with the FT-897 (interfaces to radio's ACC connector)
Datong ASP Automatic RF Speech Processor
  • Provides automatic gain control and bandpass filtering for microphone audio
  • 0 / 6 / 12 / 18 / 24 / 30 dB compression
  • Compression is done at RF to avoid distortion, and even high settings don't sound absolutely horrid!
  • With microphone level input and output, it is prone to hum-inducing ground loops when operated off the station 13.8 V supply—you DON'T want to know how I fixed that... (It could also be used with batteries, or a separate wall-wart transformer, either of which would immediately resolve the issue.)
Behringer Shark DSP110 Signal Processor, which seems to be essentially the same as the Behringer Shark FBQ100
  • This device is an audio "Swiss army knife": It contains a microphone preamp with gain control, it provides phantom power, it can convert between mic and line levels either way, as well as unbalanced to balanced like a "DI box".
  • It includes an effective low-cut filter and noise gate—these make a cheap wireless mic sound much better in a PA application!
  • The compressor seemed not to do anything, but measurements I made indicated that it does actually work—it just doesn't produce any nasty artefacts even with aggressive settings! However, I would not recommend this unit as a compressor for ham radio use regardless.
  • Also includes an adjustable digital delay line. Besides making annoying echo effects, it could be used together with an analog compressor to obtain "zero attack time" compression.
  • It has automatically adjusting feedback destroyer filters—not so useful for ham radio use, but they are somewhat effective in PA use. Nothing magical, though—place the mic directly infront of a loudspeaker, and you will get feedback, filters or not...
Behringer Eurorack MX2004A mixer
  • Eight mono input channels with mic or line level input, phantom power, gain control, 3-band semi-parametric equalizer and Insert connectors
  • Four stereo input channels with 4-band equalizer
  • Two stereo output buses and two mono AUX-buses
  • Custom modifications:
    • CH1–CH8 AUX2 changed from post-fader to pre-fader (as instructed on page 24 of the User's Manual)
    • CH1–CH4 Inserts changed from pre-Eq to post-Eq (read more about this mod)
  • This is being put into use for mixing and routing audio between my microphones, radios, broadcast receiver, PC, speakers and headphones
  • Underneath the mixer sits an Alesis 3630 dual channel compressor. For now I'm using it on the RX audio of the TM-V71E.
Realistic SP-150 Communications Speaker
  • Just a basic speaker, nothing more
  • Sounds better than the radio's internal speaker
  • You can see an identical (but differently branded) speaker in the Apollo 13 movie!   :)
  • Next to the speaker are the radio's external power/signal meter (homebrew) and a radio-controlled (DCF77) UTC clock
Heil Pro-Set Plus! Headset
  • Selectable HC-3 and HC-4 electret microphone capsules
  • Good acoustic isolation in headphones
  • Phase reversal switch in headphones actually helps sometimes!
  • Quite comfortable to wear even extended periods of time
Diamond GZV-4000
  • 40 A switching power supply
  • Voltage adjustable 5–15 V (who needs anything but 13.8 V?)
  • Small, light and quiet (even without a fan mod), no RF noise
  • With West Mountain Radio RIGrunner 4012 Powerpole distribution strip
Home-Made Copy of Butternut HF-9V Vertical Antenna
  • Covers all bands from 80 m to 6 m
  • Power capability is ridiculously high for my 100 W station
  • Made of aluminum tubing, hose clamps and various scraps
  • Doorknob capacitors were purchesed from eBay
  • Fiberglass insulators are home-made
  • More information on this antenna
Home-Made Quadrifilar Helical Antennas for VHF and UHF
  • Made of 3/16" Ni-Cu brake tubing and sewer pipe
  • Right-hand circular polarization covering the entire sky for satellite use
  • Enough radiation to the horizon to reach the local repeaters
  • Fed through a Diamond MX-3000N triplexer (23 cm port unused)
  • More information on these antennas and NEC2 simulation results
  • There's also a program to make NEC2 models of QHAs
  • Here's some more QHAs I have made
Home-Made Travel-Ready VHF/UHF Yagis
  • Uses sections of a telescoping 8-meter fishing rod for mast and boom
  • Five elements on 2 m and eight on 70 cm (dual band) or six on 2 m (monoband)
  • Single 50-ohm feed by coax with a choke balun
  • More information on these antennas, including dimensions
  • I use these antennas with my Wouxun handheld (see below)
Baofeng UV-3R Mark-II VHF/UHF Handheld
  • Really tiny, with 2 W output on 2 m and 70 cm bands
  • CTCSS, DCS, repeater shift, FM brodcast band reception
  • With Nagoya NA-666 antenna: Quite impressive performance, actually
  • Here is a modification to disable the annoying "Alarm" function!

Wouxun KG-UVD1P VHF/UHF Handheld

  • 5 W output on 2 m and 4 W on 70 cm bands
  • CTCSS, DCS, repeater shift, FM broadcast band reception
  • With Diamond SRH-771 antenna for impressive looks
  • Claims IP55 protection
Both radios are excellent for the price. No wonder they are so popular. Both are well made and don't look or feel cheap or nasty in any way. Here are some of my early observations on the Wouxun. The Baofeng worked fine right out of the box (earlier versions had issues with RF harmonics and AF volume). Nevertheless I did some measurements and modifications on it first.

Both radios are supported in Linux by CHIRP. Also, the UV-3R software (ver. 1.11) and the KG-UVD1P band limit software both install and run just fine under Wine. I used these to set the band limits to the Finnish ham band allocations, to prevent inadvertent out-of-band operation.

Baofeng UV-5R VHF/UHF Handheld mounted as a Bicycle Radio
  • 4 W output on 2 m and 70 cm
  • With the 3800 mAh extra capacity battery and modified speaker mike
  • With a vibration-isolating base for mounting onto my bicycle handle bars
  • Feeding into a homebrew dual-band J-pole antenna mounted on the bicycle's front wheel fork
  • This is also well supported in Linux by CHIRP. The newest version will also set band limits!
  • Just one problem: Would a bicycle station be /Portable or /Mobile?

Yupiteru MVT-9000 Mark-II (M3) Scanning Receiver
  • Continuous frequency range 100 kHz – 2.0 GHz
  • FM, WFM, AM, NAM, and USB, LSB and CW modes
  • 1000 memories in 20 banks, 20 scan bands, 10 priority channels
  • Bandercom M3-modification (improved scan speed, decreased intermod)

Commtel COM216 Scanning Receiver

  • Continuous frequency range 25 MHz – 1.3 GHz
  • FM, WFM and AM modes
  • 400 memories in 10 banks + priority channel
  • Similar to the Realistic PRO-26 and the Uniden UBC-3000XLT.
  • Here is some more information on the COM216 and a brief user manual
Test equipment in my lab:

Antti J. Niskanen <uuki@iki.fi>