• Get involved.
    We want your input!
    Apply for Membership and join the conversations about everything related to broadcasting.

    After we receive your registration, a moderator will review it. After your registration is approved, you will be permitted to post.
    If you use a disposable or false email address, your registration will be rejected.

    After your membership is approved, please take a minute to tell us a little bit about yourself.
    https://www.radiodiscussions.com/forums/introduce-yourself.1088/

    Thanks in advance and have fun!
    RadioDiscussions Administrators

Winter reception better?

In this market, there is a low power TV station on channel 35. I left an analog TV up so I can at least check in to see what they are doing. They have a local Sci-Fi/Horror movie show hosted by The Son of Ghoul. Over the past several months, the picture has been quite snowy. At a weekend "convention" for Cleveland's best known hosts - Ghoulardi and Hoolihan and Big Chuck - I ran into the Son of Ghoul who was there selling videos. I talked to him about the reception issue, and he suggested that I tune in again during winter because the signal is better in winter. Is this likely to be true?... and ... can you give me some tips on increasing the quality of reception. I have a TV in one corner of a room, and have a little indoor UHF antenna attached to one of the upraised rabbit ears. Also, is 2012 they year that the low power stations have to go HD?
 
You would greatly improve the reception of that LP station by putting a UHF yagi type (multi-element) antenna on you roof...or as high and "in-the-clear" as possible. A few years ago we had a low power station on Ch62 here in Lexington, KY. I live about 6 or 7 miles from their antenna and saw mostly snow with some audio using an indoor antenna. I also have an external TV antenna at the top of my ham radio tower (about 55 feet up). I received a perfect picture when using that antenna. That station failed to survive because the cable company would not carry it for some reason and few people liked the idea of putting an antenna on their roof to watch it....
 
Down here in the "troposphere", the part of the atmosphere where all the weather takes place, and where most of the moisture resides....
Yes. The density of the troposphere varies on a daily ("diurnal") and a yearly ("seasonal") basis. So, mornings are better for reception than early evenings, and winter is better for reception than summer. Your best reception would be in the mornings in the winter, worst would be late afternoon and early evening in the late summer.

For things like AM radio and shortwave (all below 30 MHz or so), the upper atmosphere (ionosphere) does most of the work, reflecting long-distance signals. That's a different mechanism.
 
I don't see tropo enhancement or tropo ducting being better in the winter than the spring or summer.

When I lived in New Jersey, the winter was always a lousy time for that kind of TV reception.
 
Almost without fail, the best Tropospheric reception for me in south FL has been March to May. I had an extreme situation in early July 1992, but generally it's those spring months.

Tropo is the main type DX (the only type?) that affects UHF.

cd
 
Not talking about "Tropospheric Ducting" or "enhancement", but merely regular-every-day "Tropospheric Propagation"....meaning the signals that have both ends of the "circuit" within the troposphere. The weather-creating troposphere is what affects them.
 
Daytime AM Groundwave can be remarkably better in the winter than in the summer. This has been the topic of Radio Engineering articles, and is supported by numerous applications, signal strength meter, and scanning results. It's also true at night but harder to measure due to interference, except on high power and Class A AM stations.

I did bandscan FI measurements summer and winter at various locations in Michigan in the early 1990s. The winter FI measurements done on many stations 10-250 miles away were as much as four times the summer values. The highest ever were when the outside temperature was -15 degrees F.

Florida and California results may vary. There have to be extreme temperature variations to get the largest variation in FI.
 
Schroedingers Cat said:
Daytime AM Groundwave can be remarkably better in the winter than in the summer. This has been the topic of Radio Engineering articles, and is supported by numerous applications, signal strength meter, and scanning results. It's also true at night but harder to measure due to interference, except on high power and Class A AM stations.

I did bandscan FI measurements summer and winter at various locations in Michigan in the early 1990s. The winter FI measurements done on many stations 10-250 miles away were as much as four times the summer values. The highest ever were when the outside temperature was -15 degrees F.

Florida and California results may vary. There have to be extreme temperature variations to get the largest variation in FI.

Very true SC. I've found over the years that AM groundwave is definitely better in the winter at our latitudes. Night reception is better too if for no other reason than static levels are lower.
 
If you have a lot of trees around your home, UHF reception in the winter can also improve when trees shed their leaves. I had a situation where I had my Channel Master 4228 pointed east to receive a digital channels from a neighboring market. The lot directly to my east was heavily wooded and I always had better reception on UHF in the winter after the leaves dropped. I also improved my reception by lowering my antenna mast so it was looking beneath the tree canopy, instead of into it.

I think that much of the winter groundwave enhancement on AM is caused by lower sun angles. KGOW 1560 Houston is 200 miles away from my location and a regular at noon in the winter, but can rarely be heard at noon in the summer. Winter AM reception is also improved by the fact that there are fewer thunderstorms and less lightning. I would tend to believe that winter groundwave enhancement is more pronounced the farther north you go as sun angles decrease.
 
I didn't know AM groundwave was better in the winter.

These better reported daytime winter groundwaves aren't the result of added daytime skywaves?

From all I've read, AM groundwaves are the product of ground conductivity which varies depending on the particular soil, rock, what's on the land itself, whether there's water or especially saltwater.

If ground temperature is another factor, I guess it's something that's not mentioned in the usual literature about medium wave propagation.

If daytime groundwaves are better in winter, I should have done all my saltwater daytime DXing at the Gulf and on the east coast in the winter instead of the spring and summer.

But again, I wouldn't know if skywaves were also enhancing the signals.
 
I couldn't tell on the surface the difference between groundwave & skywave, except the latter has fading, however brief.

I spent 3 days in very late June 2005 in Bermuda to find out what AM stations from the States or other territories are heard in Bermuda in the dead of daytime. Every catch had to have been groundwave, being that time of year. Any fading was mostly "throbbing."

If I did this research this month, I am sure that more stations would come in, but that'd be cheating (more skywave)!! :)

cd
 
Well all I can say from experience is that living here in the midwest I usually found mid day reception of stations that were on my groundwave fringe in the summer to be better during the winter. I have no scientific proof, just from my listening experience.
I am not talking about winter daytime skywave which fades from time to time. I am strictly referring to stations which I can't hear or barely hear during the day in summer coming in mid day during the winter with better & steady signals. The stations that are not subject to fading.

Living in the Chicago area examples of this would be stations from Detroit or St Louis coming in better on mid winter days.
I'm sure this would not work as well in southern latitudes.
 
It's not just the amount of groundwave signal being received - it's also the amount of interference against which it has to compete. Ambient electrical noise is generally considerably lower in winter, especially in southern states where summertime brings an almost constant string of thunderstorms and thus lightning. It doesn't take much lightning (even at a considerable distance) to raise the ambient noise floor pretty considerably.
 
So you're saying it's not just the actual sound of the lightning static with each strike but the presence of all that electrical energy causes other background noise?
 
I'm saying that you're hearing the fairly intense crackle of lightning close in to you...but you're also hearing an overall rise in the background noise level from lots of other lightning happening at a greater distance.

Think of it as sort of the lightning equivalent of the graveyard AM channels - if the station on 1240 that's 30 miles away from you were the only station operating on 1240, its 1000 watts would be heard pretty clearly over half the country. But add 200 more one-kilowatt signals on 1240 all over the country, and even if you can't pick any single one out of the muck, the cumulative effect of all those little skywave signals banging into each other is a noise floor that drowns out your nearby (but not quite local) 1240.

The end of summer lightning season is the functional equivalent of shutting down most of those distant AMs that raise the skywave noise floor. (And that's not even getting into some other aspects of winter DX like auroras, which can disrupt normal north-south skywave signal paths in interesting ways.)
 
I see what you're saying about the cumulative sound of distant lightning.

Even during the winter when there's lightning in only one isolated part of the country at night hundreds of miles away, I can hear it and I assumed it was traveling on skywave.

OK, but what about during the day in the summer when all that distant lightning can't travel to your location via skywave and there's only a groundwave path?

How does it then account for a rise in the background noise floor in the middle of the day?
 
There was a very good article from a Broadcasting Engineering Journal about the temperature variation, that was published in book form with several other articles. It seems two of the signals he measured were WABC and WMTR. WMTR took a huge drop or increase duuring the course of one day. WABC had a big difference also but not as big as WMTR. I think he was in New Jersey when making the measurements.

My own FI Meter measurements were done in the same location for summer and winter. I remember one was a 1240 in Michigan over a 12 mile path. It was 3.0 mV/m in the winter and 1.05 mV/m in the summer. Could have been fading at times, but it would be very high angle for skywave at 12 miles.

Everything points to a real difference, scanning, signal strength meters, FI meters, and just plain quieting level of marginal signals in winter vs. summer.
 
pianoplayer88key said:
I remember being about 5 km east of 1170 KCBQ's transmitter a few weeks ago, and I could hear what sounded like skywave fading on their signal.

In the daytime?

Were you in a null? Were you driving near high tension towers?
 
I'll give you another example.

I had a Realistic STA-111 Receiver in the early 1980s, located about 60 miles from WJR. The signal meter had seven LED segments. I followed it for several years. In the summer, three LEDs lit. In the coldest part of the winter, 5 LEDs lit. In between, 4 LEDs lit. This happened year after year like clockwork. I had a Sony CF-450 with a signal meter in the same location. In the coldest part of winter, it would register at about 6 on the scale. In the summer, it registered about 3 on the scale. WJR has a 195 degree tower with little skywave at the elevation angle corresponding to 60 miles. The only time I ever heard fading there, they were on a much shorter auxiliary antenna.

Same radio, early 1970s, visiting about 90 miles east of WMAQ. About 4 in the coldest part of winter, 2 in the summer.

Day night pattern and power changes also result in consistent changes in the readings, after the initial "AGC signal bounce" occurs.

These were all daytime observations. The CF-450 seemed to have a logarithimic response to signal strength, common with some AGC circuits. The difference between a signal strength meter and an S meter is essentially calibration. Every meter is different, but at the same location, differences in readings are significant.
 
Status
This thread has been closed due to inactivity. You can create a new thread to discuss this topic.


Back
Top Bottom