Many thanks to SWLing Post contributor, Bob Colegrove, who shares the following guest post:
What’s Your Favorite Corner of the Dial?
As asked by Bob Colegrove
Let’s suppose you’ve been listening to radio for a while. Consciously or not, you’ve probably favored a range of AM, SW, or FM frequencies. These are areas where you go to DX or just listen to your favorite stations. One area I seem to keep returning to is the very bottom of the medium wave band, roughly 530 kHz to 600 kHz. With the convenience of today’s digital radios, I have consciously pushed the envelope somewhat lower.
The main reason for specializing in that frequency range is the challenge. In the very beginning there didn’t seem to be much at the extreme lower end of the AM broadcast band. Growing up in Indianapolis in the ‘50s, the local stations were all at the upper end of the mediumwave dial. WXLW held down 950 kHz – lower than that nothing. I would say the stator plates on the variable capacitor got very dusty, never being closed any further than that on many radios.
Another challenge was sensitivity. In analog times, the sensitivity of a tuned circuit had some falloff as the inductance/capacitance (L/C) ratio decreased. Sensitivity is highest with the variable cap open at the high end of the band. As you tune lower by increasing capacitance (inductance remaining constant), the Q and consequently sensitivity drop off – not dramatically, but somewhat.
Finally, not all old analog radios tuned to 530 kHz; some were even challenged to tune 540 kHz. By performing a little mischief with the alignment, I could sometimes venture into unknown territory.
This was all part of the challenge. So, what could I do to coax some activity out of the bottom of the band? I spent many hours poring over Bill Orr’s Better Shortwave Reception (Radio Publications, Inc., Wilton, CT, First Edition, 1957) and tweaking caps and coils trying to squeeze the last few kilohertz and microvolts out of my radios. This exercise fascinated me and became a hobby within a hobby. If I may be allowed a self-deprecating aside here, the first time I took a radio out of the cabinet, I just assumed that all these alignment screws were loose, and dutifully torqued them down. The alignment problem is not comparatively complex with today’s digital receivers. Note, I didn’t say it was unimportant.
I still tend to favor the bottom of the medium wave band. Below is a list of my catches over the past couple of years. It’s just a sample of what one might hear by casual listening over time. Highlighted stations are heard during daylight hours. This is NOT intended to impress anyone, rather it is hopefully a stimulus for your own efforts.
As another attraction of the lower mediumwave band, you will find a potpourri of stations. Besides regular North American broadcasting stations, one might possibly hear an occasional high-powered trans-Atlantic station which is not synchronized with the 10 kHz spacing. 530 kHz is interesting. It is not used in the US by commercial broadcast stations. Instead, stations from Canada and Cuba at roughly orthogonal directions from me are regularly audible at night on this frequency. Thus, the radio is tuned by simply rotating the antenna. 530 kHz is also home to several Travelers’ Information Stations (TIS) throughout the country. Question: How will this long-time service fare if travelers don’t have AM radios in their new cars? Finally, the very bottom of the frequency range still contains a few holdouts of non-directional beacons.
Frequencies below 530 kHz probably put a strain on the medium wave bands of old radios, but they are likely no problem on most digital radios having both LW and MW coverage. As mentioned, there are a few non-directional beacons down there. They are Morse coded using amplitude modulation. I have found placing the receiver in SSB mode makes detection much easier, as the heterodyne from the carrier can be heard well before the signal is strong enough to produce any audio. These beacons generally fade in for brief periods of time and then fade out like passing comets.
My most recent catch was experimental station WI2XLQ, 486 kHz, during its annual Fessenden Event on Christmas Day and again on New Year’s Day. See https://swling.com/blog/?s=Fessenden+ . The experience was not the armchair listening quality one might expect from FM or the Internet. Instead, it was weak and fraught with atmospheric noise. The station came in periodically, then disappeared, in short, DXing to its highest degree of satisfaction.
The antenna is the key to good reception, and there is no exception to this rule at the lower end of the AM band. Many years ago, I switched to an indoor, resonant loop antenna. The selectivity, directional properties, and noise rejection of a loop antenna in this frequency range are superb. The figure below shows my 40-year-old loop antenna, which is still used in its original form. It tunes from ~485 kHz through ~1710 kHz in two bands. The antenna can rotate 360 degrees horizontally and 90 degrees vertically. Further, it is mechanically balanced to remain in any position without locking. For those not inclined to construction projects, the Tecsun AN-100, AN-200, and Terk Advantage will perform quite well through inductive coupling with a portable radio’s ferrite bar antenna.
As all experienced medium wave DXers know, for success you need to have patience, “set a spell,” and let the radio do its thing. Radios are living organisms, kind of like cats, very independent at times, and will let you hear only what they want you to hear. On many channels, stations will come and go over time. If you’re lucky, you might catch an ID; lacking that, you might be able to identify it by the format or network. You might try to compare the contents you hear on the radio with what you can hear online either over the station’s website or via streaming sites such as TuneIn, iHeart, or Radio Garden. There may be a delay between the Internet stream and the live signal.
When you feel you’ve exhausted the possibilities, there’s still more. Turn the antenna 90 degrees and start over. You’re only half finished with that frequency. Don’t forget a headset or earbuds.
What’s the next challenging rung on the limbo bar? Well, possibly the 633-meter ham band, 472 to 479 kHz. I’ll have to pad the old loop with a small capacitor to tune down there.
What’s your favorite corner of the dial? Why?
The CRTC has just approved the flip from AM to FM for CFOS 560, Owen Sound. The deadline for the change is October 31, 2026. Their new frequency will be 89.3. There will be a 3 month simulcast period. Full decision here. https://crtc.gc.ca/eng/archive/2024/2024-265.htm
I live about 3 km. from the transmitter site of 560 CFOS, Owen Sound, ON. CFOS Has an interesting lobed transmission pattern to protect AM stations to the south west and north east. It means that 30 km to the west, on the Lake Huron shore, the station is inaudible. You can see the pattern here. https://radio-locator.com/info/CFOS-AM
CFOS has also applied to the CRTC to flip to FM on 89.3 and 1,500 watts. A station contact tells me that if the flip is granted, they will simulcast on AM and FM for a time and then fully flip. Catch it while you can.
HF Aero bands mainly 8 and 6MHz
in the daytime i listen to 14.300 mostly, sometimes CB radio when the band is open to DX, in the evenings 40 meters ham and after dark 80 meters ham, i have a loop made from about 85 feet of #14 stranded copper wire fed with 50 ohm coax and an ugly balun in between coax & antenna
OK, another interest of mine is trying to catch stations on 920 kHz. Why, you ask? I have a local on 920. They used to go off the air at sunset, but now they switch to a nighttime pattern and reduce power slightly, and I am in a pattern null. I’ve caught three more stations there. My best catch there was WLIV that is listed as running 38 watts after sunset (that’s just over 5 mi/w). Now, whether they had reduced power at that point or not, I don’t know. I sent an email to the station manager asking about that, but from his reply I don’t think he knew what I was talking about.
That kind of spun off to an interest in catching other very low power stations after sunset. So far I’ve caught WNYV on 1070 (28 w, 16.6 mi/w) and WCPC on 940 (7 w, 32.57 mi/w).
Great article! I’m intrigued by both the low end and the high end of the MWBCB. My best low end catches were CHLO in Brampton, ON, and CMBQ in Cuba, both on 530 kHz. I’ve logged domestic stations on 540, 550, 560, and 570. Best DX was WVOC on 560 from Columbia, SC.
On the high end, the expanded AM band from 1620 to 1700 is a great place to search because it is less crowded, with only a few US stations and with (I think) a 10 kw maximum power. I’ve logged stations on every frequency up there except 1640.
I’m really proud of having caught WQFG689, a TIS and the only domestic station on 1710 kHz. How much power? They were licensed for 10 watts but some time ago received a temporary authorization for 100 watts, and I don’t know if they still run that or had reverted to 10 watts when I heard them.
I have another interest that I will put in a separate posting.
After writing that I didn’t have 1640 kHz in the log I realized that I hadn’t done much MW DXing in a while. So, I pulled out my Qodosen DX-286, sat down under a shade tree, and took a listen. And there was WSJP in Sussex, WI (408 mi) on 1640, weak but identifiable on the whip antenna. I hung a reel antenna in a tree and got a better signal, checked their website to make a definite ID, and then went down to search for LW beacons. 🙂
“…the first time I took a radio out of the cabinet, I just assumed that all these alignment screws were loose, and dutifully torqued them down.”
Now, that’s funny right there!
Truth be told, one of my earliest forays into shortwave was blindly fiddling with IF cans on a transitor AM radio, and being bewildered as to the foreign language broadcasts I started receiving! (Mind you, this was the early 80s, when the SW bands were FULL.) Luckily, a local ham had just become my Elmer, and clued me in to what was going on.
Yes, and to think this was all done by ear without benefit of a signal generator or meter. After a long period of tinkering and discovery, the amazement was not that it worked reasonably well, but rather that it worked at all.
My first SW radio was an old console, which, as I would eventually learn, had an unusual IF of 465 kHz. I somehow got it to resonate into the lower region of the BCB. This created an incredible oscillation and drove the magic eye tube into apoplexy.
With some radios having 250+ Vdc B+ and others with an AC-DC chassis, it’s a wonder we are here to tell about it.
No more E-mails from The Shortwave Post please don`t E-mail me again thanks
Business Radios and Lorry drivers conversations in the UK, I used to live near the A1 and lorry driver convos were very funny.
Thanks for the insightful article, Bob! I’ve always found myself gravitating toward the lower end of the dial. It’s funny—growing up, it felt like the stations down there had more variety and less crowding. Even now, I tend to stick below 1000, just out of habit. But I guess it’s time to explore the upper end a bit more, something I’ve never really paid much attention to. Maybe it’s time for a little change and some new discoveries. Cheers,
Excellent! Made me remember when I took out the A?A of my youth from its bakelite whatever it’s called. One difference though: I was after SW bands any station I could get.
Thanks.
That is AGA, not A?A…
WHAT a wonderful read. I too spent far too much of my younger life fiddling with the family radio (don’t break it will you Andrew!) in an effort to see what was going on a bit further down the dial, or up it. It was a Sunday morning when I was ‘going up’ that I heard a conversation between two people discussing technical matters. It turned out that I had happened across the 160 metre band (fondly still called ‘Topband’ even today) and luckily at that time most of the activity was Amplitude Modulation, requiring no special product detectors or BFO’s. And there started my voyage across the bands, from VLF to UHF, collecting my Amateur licence along the way. My favourite corner? ALL of it!
Wow, Bob, you did, indeed, inspire me.
There’s nothing I like better, when the Better Half has turned over and is seeking “the land of Nod,” than to clamp on some headphones and tune around to see what’s out there.
Now you have given me an interesting place to hunt. I might even take a crack at it with the “nitro-burning” CCrane EP-Pro,
I run the Radio Monitoring Net — https://thebig94.wordpress.com/the-scanner-enthusiasts-net/ — on 146.94 on Tuesday nights and often send out a “Useful Goodies” email blast to net participants afterwards.
Might I have your permission to turn your post into a PDF and distribute it? I won’t do it unless you say Yes, and I will, of course, give credit to SWLING Post.
Cheers, Jock
Great article, Bob!
I would agree, the lower end of the dial has always been attractive to me, so much so that I really need to work on the upper end – it’s my least favorite since I was a kid. Back then there were so many stations seemingly overlapping each other, that I tended to move downward. Most of my listening as a kid was below 1000, and much of it below 800.
It’s funny how that pattern has been a life-long one – I guess I will have to try to teach an old dog new tricks and play up the band.
Cheers! Robert