Monday, December 14, 2009

DXing The Shortest Days

It's that time of the year again when the days are the shortest and the nights the longest. There are barely 10 hours of daylight here in southwestern Arizona, as the sun is rising at 0724L and setting at 1722L. D-layer absorption during daytime hours is at the lowest this time of year. Today, at the noon hour, I went on a little mini-DXpedition to a nearby hilltop which gave me a 360 degree view. I started DXing at 1130 local time and continued till about 1230 local.

Radios used were the Tecsun PL-600 and the unassisted truck radio. The Tecsun PL-600 was assisted with the 24-inch box loop. Here are the highlights:

660 KHz, 1130L, KTNN, Window Rock, AZ. 50KW (truck radio). Medium strength, but easy. 327 miles.

740 KHz, 1135L, KBRT, Avalon, CA (Catalina Island, "26 miles across the sea"). 10KW (PL-600 and truck radio). Strong on the truck radio and overriding KCBS, San Francisco. 239 miles.

760 KHz, 1145L, KKZN, Thornton, CO. 50KW (PL-600). 675 miles at the noon hour! Progressive Talk Radio. Signal was in and out, weaker and underneath San Diego's 50KW powerhouse KFMB. I was able to partially null KFMB using the box loop, which made the difference. Great daytime DX.

1090 KHz, 1221L, XEPRS, Rosarito, Baja California, Mexico. 50KW (PL-600). Weak, but readable, peaking to medium at times. This is Baja's XX Sports Radio, broadcasting in English to San Diego from an appreciable distance down the Baja peninsula. Studios are reportedly in San Diego. 186 miles.

1120 KHz, 1210L, XEMX, Mexicali, Baja California, Mexico. 400 watts (PL-600 and truck radio). Broadcasting oldies. 100.9 miles. Good reception for 400 watts.

Now for the amazing "pipeline" station, which always seems to put some kind of a signal into southwestern Arizona at any time of year:

700 KHz, 1225L, KALL, N. Salt Lake City, UT. 50KW (PL-600 barefoot and truck radio). 514 miles.

KALL is the amazing one, not for distance but for signal strength. Though I have heard this one before during the daytime, this time of year it seems to have a pipeline into the southwest. Signals on the unmodified truck radio were absolutely astounding. Note that the distance here is in excess of 500 miles at the exact center of the daylight period. Shown is the beautiful location of KALL's tower array.

Try some daytime DXing during this time of year, particularly near mid-day. You might be surprised at what you can hear.


Stephen said...

I guess I'm not the only one who seems to have a daytime AM DX hobby. :)

I thought I heard KTNN once here in El Cajon, CA, on my PL-380 and Select-A-Tenna but it turned out to be a spur from 540 XESURF Tijuana, BCN.
KBRT comes in quite well here on my PL-380, usually hitting about 46-48dBu in the daytime. KCBS is absent obviously, but with the help of the Select-A-Tenna, I have heard 680 KNBR next to 690 XEWW, 50kW @ 32 miles ( ) and 810 KGO next to 800 XESPN Tijuana (unsure of power & distance). ( )
Interestingly, KFMB is only 5kW in the daytime, but 50kW at night. (I posted a comment about that on another blog post.)
Also, 1090 XEPRS seems to operate with their nighttime directional pattern 24/7. I believe their studio is inside Petco Park somewhere, or it may be up north a bit, but I'm not sure.
I'm closer to Mexicali than you were, and 1120 is completely swamped by 1130 KSDO, 10kW @ 6 mi, would be ~72dBu on my PL-380 if it didn't have the 63dBu cap.
As I mentioned in another comment, I have faintly heard KALL here in the early afternoon in March. I suspect that if XEWW 690 was off the air, I would have an easier time with that station.

Now... for a daytime DX station you didn't mention... probably because you're closer to it than I am and it wouldn't be considered a "good catch" for you. On some winter days, I've been able to hear 1580 KMIK Tempe, AZ, at noon, over co-channel 50kW KBLA Santa Monica, CA (which is normally the dominant daytime station). At night, KMIK is usually my strongest nighttime station, regularly hitting the mid 50s dBu on my PL-380, and I've actually seen it as high as this a few times using only the built-in loopstick:

Radio-Timetraveller said...

Hi Stephen,

Glad to see another daytime DXer about. Not many seem to thrill at daytime DX.

For the last four years I have been spending my winters in western Arizona at Quartzsite, just 20 miles east of Blythe, CA. I gather you have noticed some of my posts are referenced from there. In fact, I'm headed there again this fall in about three weeks.

Your area sure seems to be filled with strong mediumwave RF, and I'm sure that is much of your problem in hearing the weak stuff. At my place in Arizona there are only a couple of AM stations within 80 miles or so, and they are relatively low power. So as you can imagine, the DXing is great.

KALL-700 is in routinely almost all day long. I can often get it on my truck radio. It is 514 miles distant, with its signal pattern headed right at me with 4dB gain.

I'll have a listen for KMIK-1580 when I'm out there and see if I can hear it during the daytime. I don't see why not.

The San Francisco stations are all readable during much of the daytime too on my Eton E1 with longwire, or with the help of a loop on the ULRs. They are in the 550 mile range.

Radio-Timetraveller (Bill)

Stephen said...

You think the strong MW RF is bad at my home location? You should see it at my grandparents' house in San Gabriel. (I'm there right now with my parents, as my grandpa's in the hospital and it may be his time to go.) They're 1/3 mile down the street from KAZN-1300 and KMRB-1430, and 4.8 miles west of KDIS-1110, and right now even on their reduced-power night patterns (with KAZN at a different nighttime site, IIRC), I'm getting 57dBu on KDIS's IBOC carriers +/-12kHz, and 49,00 desense from about 1080 to 1710, sometimes touching 50,00 in some places like 1260 to 1450!