• 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

WHAM's Signal

Mike Sheridan

Mike Sheridan

Someone here will know the answer to this....

WHAM is a 50KW non directional yet they appear to be much weaker than the other non-da's WGY, WFAN, WCBS, WABC and directionals like WWKB, WQEW,WBBR and WOR.

I know there is a problem with Cuban interference on 1180 (due to the VOA station in Marathon) yet I don't hear a lot of it on 1180. Does WHAM have an absence of sky wave or something?
 
El Nino...or whatever else is goofing up the recent weather patterns. :D :D

(call on Freebird or Fybush...they know more than the weather guys!!)

HDBG
 
heydaybegone said:
El Nino...or whatever else is goofing up the recent weather patterns. :D :D

(call on Freebird or Fybush...they know more than the weather guys!!)

HDBG
Click to expand...

Or Al Gore. He invented weather and the radio, among other things. ;D :D
 
Where are you listening from? The ground conductivity in this part of the country isn't that great, and the 50kw ground wave signal on 1180 starts to fade between 60 and 80 miles. The nighttime sky wave doesn't kick in until around 150 miles, depending on season & propagation conditions. That leaves a fairly large zone of silence in between. Using WGY as a comparison, their ground wave signal on 810 will go a lot further than 1180 anyhow. If you are comparing WHAM's ground wave reception to WGY's sky wave, then you have to consider your location in relation to both stations.

In addition, the HD sidebands and processing can make an analog AM signal sound weak because of the added noise and limited audio frequency response. Plus, there's tons of interference from a world full of digital devices that didn't exist when the clear channel stations were built in the '30s and '40s. Plus, there are several other stations on 1180 that weren't always there. Etc. Etc.
 
"Ground conductivity in this part of the country isn't that great...." ???

Huh?

In Rochester it's mostly 4, and at the south end of Conesus Lake, it changes over to 8. In the southern reaches of the Metro - primarily in Rush, Henrietta and Brighton - it's 15, with patches of 30! Cf. with rocky, sandy New England and much of Pennsyltucky where you find conductivity of 2, 1 and even 0.5. It doesn't get much better than the Rochester metro for AM in the Eastern USA. (Source: FCC M3 map along with recent measurements. "30" is as good as conductivity gets on dry land - coastal stations in salt marshes can enjoy conductivity of 5000, but that's the only area where you find that kind of thing.)

The real reason for WHAM's signal issues, IMO, is what Dr. Rust correctly diagnoses as HD toxicity. Yes, the limited analog frequency response (to about 4.5 kHz, less than half that permitted under the rules) doesn't help. But the real problem is the high-amplitude steady-state OFDM carriers in the sidebands. Your radio has a circuit that ratchets back sensitivity when it encounters strong signals to prevent your ears from getting blasted when you tune from a weak station to a strong one. Those digital saddlebags on WHAM are detected along with the desired center carrier, and their high constant-on state throttles your radio's ALC. So the station sounds weak even if you're miles from the transmitter.

HD has fooled more than a number of managers who thought "digital" meant their stations would sound better. HD also fools analog radios into thinking AM signals are way stronger than they actually are (to the 99.99999999997% listening in analog mode.) ;) :D
 
Bob, my M3 map is not as detailed as yours, showing conductivity of only 4 to 8 millimhos per meter in WNY, which seems fairly midrange. However, you're the one with a doctorate in AM, not me.

Anyway, regarding HD, I recently had a conversation with a woman who mentioned that she no longer listened to WHAM in her car while driving to and from her home near Geneseo because the signal "had gotten weaker". I just nodded and didn't get into a technical discussion of HD, because she had no idea what it was and didn't seem too interested in knowing.
 
I am in Charlotte, North Carolina and although I have occasionaly heard WHAM it's always been weaker than the rest.

The ground conductivity here in Charlotte really sucks, no more than a 2 or 3 in most of the area where I live.
 
Yeah, the M3 map is approximate, and outdated as well. The general trend is for conductivity to gradually decrease due to development (expressways, parking lots, interchanges and new buildings) but there can also be pockets of higher conductivity when real measurements are taken.

My comments were derived from measurements made over the past ten years or so in the region.
 
Status
This thread has been closed due to inactivity. You can create a new thread to discuss this topic.


Back
Top Bottom