High Noon: Belka MW shootout part 2, with a review of the AFA200C active MW ferrite antenna
When I reviewed the updated Belka (gen3, 2022) for its MW/LW performance in October last year, I just wanted to know if it’s any good with just the whip antenna and used the XHDATA D-808 as a reference radio because it’s a Jay Allen 2.5-star average performer on MW and my expectations were not high for MW reception on a short whip. To my surprise that average bar turned out way too low for the Belka!
That was sure asking for a comparison with the most sensitive MW radio I have and gave me hope to use the Belka for ultra-portable MW DXing on the move. The omnidirectional whip doesn’t allow me to null out unwanted co-channel interference though, therefore I wanted to find a reasonably sized loopstick antenna to pair with the Belka. Continue reading →
Many thanks to SWLing Post contributor, Bob Colegrove, who shares the following:
A Rack of Radios
by Bob Colegrove
You simply cannot have enough radios – a principle I learned a long time ago. The difficulty occurs when it comes to storing them and yet having them at the ready when necessity calls. Turns out several of my portables fall within a dimensional range that they can be conveniently stored in a rack on the table.
I would like to say I made a project out of this choosing a fine hard wood for construction, carefully routing each divider into a finely milled slot, tastefully finishing the whole thing off with appropriate stain and varnish, and perhaps lining each slot with felt of finest virgin wool. However, never having been one to let form triumph over function, instead, I found a couple empty cracker boxes of the right dimensions, made a few cuts with a hobby knife, and applied some hot glue. Whalla!
Wait a minute. Is that an unused slot at the end? Hmm!
I love it, Bob!
I mean, you know those cracker boxes just wanted to become a custom radio rack–! I say save the fine wood working to build the shelf upon which you’ll place your bespoke cracker box radio rack.
It was the survey that Thomas, our Maximum Leader, conducted that got me to thinking about this.
The survey revealed that portable radios were used 38.6% of the time by SWLing Post readers as their “daily driver.” I like portable radios, too, and use them frequently. Hold that thought for a moment.
I also like medium wave DXing (content DXing, really, I enjoy tuning around for unusual programs) because, as Gary DeBock once put it: “It’s a target-rich environment.” With that in mind, I was exploring the CCrane website and found a couple of items – the Terk AM Advantage and the Twin Coil Ferrite® AM Antenna Signal Booster that looked like they might help portable radio listeners who want to pull in medium-wave signals better. I asked the CCrane folks if they would like to review both products, and they sent them to me without charge.
Bottom line: they both work for boosting reception of medium-wave signals.
The Terk AM Advantage is a nine-inch tunable loop encased in plastic, and it requires no power supply. Simply place it near your portable receiver and just the dial to the desired frequency, and you could get up to a 20 dB gain in the signal you want to hear. The loop of the Terk AM Advantage inductively couples with the ferrite antenna inside your portable radio, although the unit comes with a direct wire connector that can be used with some radios.
I tried the Terk AM Advantage with my CCrane Skywave SSB on an AM that was coming in with a lot of static at my location. Without the AM Advantage, I had 3 bars of signal strength. As soon as I placed the AM Advantage close to the Skywave and adjusted the tuning knob, the signal strength increase to 5 bars, and the audio was much easier to hear with less noise.
With my Tecsun PL-880, which has a numerical signal strength meter, signal strength was 11 without the AM Advantage, but with the AM Advantage, signal strength increased to 14, and it was much easier to hear. The Terk AM Advantage definitely provides a modest boost in signal strength and clarity, is easy to use, and requires no batteries or external power supply.
The Twin Coil Ferrite® AM Antenna Signal Booster is more complicated. It consists of an antenna element that measures 8.5″ W x 2.5″ H x 1.25″D, a tuner unit that measures 3.25″ W x 4.25″ H x 1.25″ D, a small ferrite stick, and some patch cords. It comes with an AC adaptor and can also be powered by a 9-volt battery. For radios with external antenna connectors, package also includes a RCA female patch cord to two bare wire ends.
Set up is pretty easy: connect the tuner unit to the antenna element with a patch cord; connect the tune to the ferrite stick with another patch, and provide power through either the AC adaptor or 9-volt battery. (I used a battery).
Here are C.Crane’s directions for how to use The Twin Coil Ferrite® AM Antenna Signal Booster with a portable radio:
Place the Tuner Control in a comfortable location relative to your radio. Place the Antenna Element a few feet away. If the Antenna Element is placed too close to the radio, it will cause noise on your radio.
Place the Ferrite Stick on top of the radio near the center. Placement will vary depending on where the internal AM antenna of the radio is located.
For testing purposes, tune your radio to any weak AM station. It is important that the station be weak so you can clearly detect the improvement in reception.
Rotate the Fine Tune control, it will click on and the red LED indicator light will come on. Turn the Coarse Tune control knob slowly and you will likely notice a change in reception at some point on the dial. Adjust the control knob until you notice the most improvement on your signal. Now you can use the Fine Tune control for further refinement.
Move the Ferrite Stick around the radio to find the position that affects the signal the most. This position is the “sweet spot”, or the best position. Again, adjust the Fine Tune on the Tuner Control for the best reception possible. (I used rubber band to hold the Ferrite Stick in place, but the unit comes with some double-stick foam tape to hold it in place.)
Now you can orientate the Antenna Element for best reception. In most cases, the Antenna Element does not have to be adjusted again. When radio noise is a problem, try rotating the Antenna Element in the direction which reduces noise to a minimum.
And The Twin Coil Ferrite® AM Antenna Signal Booster works like crazy! With same station on my CCrane Skywave SSB, it boosted signal strength from 3 bars to full scale. With my Tecsun PL-880, it increased signal strength from 11 to 38.
In my view, although The Twin Coil Ferrite® AM Antenna Signal Booster costs twice as much as the Terk AM Advantage and is more complicated to use, it is more than twice as effective in boosting medium-wave signals.
Many thanks to SWLing Post contributor, Frans Goddijn, who writes:
I bought a vintage antenna tuner, one that does not need a power source, very basic just a box with some beautiful coils and nice big variable capacitors and it works for the big magnetic loop antenna here.
I have four GRAHN loop antennas which each have their box with dials to fine tune the signal but the big loop didn’t have that yet.
The tuner works well, filters out some noise but I must say the iCOM radio also managed to select good signal from the loop with its own tuner system and the DSP noise filter at the speaker end of the system further clears up the voice sounds.
Many thanks to SWLing Post contributor, Georges Ringotte (F6DFZ), who writes:
When I did tests on my Belka-DX, I noticed that the signal level scale was extremely accurate, each mark is 10 dB
I regretted that the manufacturer didn’t use the IARU S meter scale. So I decided to make my own. With RF Gain to the maximum sensitivity, -73 dBm, or S9, is at the 45 mark. I used Front Designer software to make a scale, with 10 dB graduations above S9, and 6db graduations below S9.
Then this scale was printed on water based transfer, 40 mm by 26 mm, when applied on the existing display.
The result is great, and now I have precise readings of signals reports.
That’s brilliant, Georges! Golly..it looks stock when applied to the screen! Thank you for sharing this!