IrvingtonVFD43
Member
Kinda a dumb question, but as I type this, WBBM 780 Chicago is sitting beneath WGAJ, 780, Norfolk, Ne. Kinda early for MW DX to reach me, but can snowfall affect MW groundwave propagation?
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MW propagation and snow
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Snow fall can't affect skip much, but it may change the ground plane of the antennas at WBBM in Chicago. Perhaps the angle of radiation or the pattern has changed a bit and you're now hearing the signal when it might ordinarily have been nulled in your direction.
I remember when I worked at a local AM radio station, the chief engineer noted to us that the reflected power changes by 10% or so from nominal value after a rainstorm. This may have an effect on the radiation pattern too.
k9rzz
Member
I think this question has been brought up before on various forums so there is probably some truth to it. Enjoy!
Ground conductivity has a major effect on the transmitting antenna tuning, something the engineer must keep on top of. The most notable are seasonal changes that are a must, bumps in the road are up to the engineer depending on how much reflected power the transmitter will safely tolerate. That being the case I can see where it also effects a receiving antenna but it may or may not be noticeable, it's anybody's guess. FYI, it looks like you're confusing ground wave with sky wave propagation, the rule of thumb is if you can hear it during the day it's ground wave, at night distant stations get to you via sky wave.
In some unusual cases you may receive both depending on distance from the transmitter, the type of transmitting antenna and a few other factors. This dual reception adversely affects listeners usually in the secondary contour at night causing fading and distortion but like I said this is unusual.
There is no definitive answer to your question however, I doubt anyone has actually studied it. Snowfall certainly can adversely effect reception by raising the noise floor due to static discharge, severe storms can be full of lightning too. When it comes to snow on the ground after the storm passes who knows?
In some unusual cases you may receive both depending on distance from the transmitter, the type of transmitting antenna and a few other factors. This dual reception adversely affects listeners usually in the secondary contour at night causing fading and distortion but like I said this is unusual.
There is no definitive answer to your question however, I doubt anyone has actually studied it. Snowfall certainly can adversely effect reception by raising the noise floor due to static discharge, severe storms can be full of lightning too. When it comes to snow on the ground after the storm passes who knows?
lanbergld
Member
Ground conductivity probably explains why I always get stronger LF & MF reception during rain. It's my guess anyhow. For me the difference is far more than slight. Even HF improves for me during rain, but granted I stay on the low end of HF (<4000 kHz). I'm describing my reception, no transmitting.
I myself can't testify about snow, since it hardly ever snows in Richmond.
Larry Lanberg
Richmond VA
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I've never noticed any significant difference so if yours is "far more than slight" I suggest you find out what is wrong with your antenna system, grounding, etc.
lanbergld
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No I like it. What are you talking about? My reception is fine the way it is, but it really improves during rain. I'm not going to complain. My receiving location is about 120 ft. above the city streets with a large indoor (passive) loop antenna. Perhaps that accounts for the difference I get versus yours.
Larry Lanberg
Richmond VA
Larry Lanberg
Richmond VA
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