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WLW and WING - interference reports?

With WLW running I-BLOCK and their harmonic being very close in frequency to WING 1410, has anyone noticed interference issues when listening to WING from WLW particularly in Mason or Lebanon? The R/L map shows the 54 dBu contour of WING pretty much going right over the WLW site. I've heard reports of WLW's harmonic on 1400 being heard as far away as Middletown.
 
It would not surprise me that WLW's harmonic is causing interference with WING. I would imagine even before IBOC there were issues with their harmonic interfering with WING in the Mason area.
 
This WING/WLW harmonic problem has been going on forever. I don't think it can be eliminated....physics, you know! Another GREAT example of this happens in Nashville, TN WSM on 650 totally trashes another 50 KW station on 1300 (also in Nashville) for several miles around the WSM transmitter. If you drive through Nashville on I-65, tune to 1300 as you approach the WSM tower. You can do the same thing with WLW. Listen to WING on 1410, and the splatter and IBOC trash from 700 totally trashes the WING signal for miles around WLW....
 
You mean .5 mv/v, Buckeye?

Is this going on during the day, night or both?

During the day at least. Not sure at night though I've read reports of WLW's harmonic dominating 1400 at night within a mile of their stick covering up the graveyard slop otherwise present on 1400. WING appears to throw a null towards Mason and WLW at night. I was looking at R/L contour maps of WING's daytime signal pattern and seeing where the red and purple lines go. Mason appears to be right in between the red 'local' and purple 'distant' coverage contours.
 
Funny, we came close to buying 1300 in N'ville.

Glad we didn't.

Night lobe is really pulled in toward the WSM transmitter site area. Really cut off from some of the money real estate.
 
Assuming that all spurious radiation is at least 80 dB down, at the 1 V/m contour, it would only be 0.1 mV/m at the most about 1.7 miles from the transmitter. I suspect that most harmonics that people are hearing are created in the receiver, though still a problem. In newfangled devices, it seems that design has forgotten that these signals have to be suppressed and filtered. One thing you never used to see was blanketing type interference in the 100 mV/m signal range. Nothing like a good old fashioned LC tuned circuit stage to improve these receivers.
 
Most AM receivers are very cheap so I would agree with you that it is the design of the tuner and nothing wrong with the WLW transmitter and site. The same problem happens when you are close to 1530 transmitter site and hear their harmonic on 630 AM.
 
Assuming that all spurious radiation is at least 80 dB down, at the 1 V/m contour, it would only be 0.1 mV/m at the most about 1.7 miles from the transmitter. I suspect that most harmonics that people are hearing are created in the receiver, though still a problem. In newfangled devices, it seems that design has forgotten that these signals have to be suppressed and filtered. One thing you never used to see was blanketing type interference in the 100 mV/m signal range. Nothing like a good old fashioned LC tuned circuit stage to improve these receivers.
Are there still some tunable IF tanks in these new radios? Wondering if this could be tuned out..
 
Nothing beats real physical L and C at the received frequency to supress such harmonics.
Even if included, varactor-tuned preselectors are likely to have offset-error that could not be easily corrected as with real L and C.

I marvel that in Chicago I hear/detect NO 2nd harmonics off the very strong 670, 720, and 780.
I'd love to see the trap/rejectors in their output networks.

670 WSCR must be a real treat, they fought for a long time to make iboc run in their weird cramped lot.
They still persisit in throwing weird analog images off the sides of its digital sidebands.
I'd be embarassed to throw out so much wideband slop, but I guess it's protected species or something.....but theere's no problem at 1340.


I have an idea that where I work, about 2 miles from the sticks of WBBM and WGN, there should be a large component
of 60 khz, just waiting for someone like me to set up a loop and rectify into DC.

Has anyone tried this?
The eng staff of WLW in the 500kw days calculated they could run a very small electric car in the near-field.

Tuneable IF tanks would help to a lesser degree. 262.5 IFs are better in this case than 455s.
 
The most we ever did with my 50KW was light florescent tubes in the phasor. The GM/Delco staff used to park their prototypes in my driveway, right in the main lobe, with its ERP of 300KW and test their cars. The radios and the electronics. Good times!
 
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