What is your reception on 820 AM at night?

[jd]

1954 Broadcasting Yearbook shows WEAW as a Construction Permit with 500 watts, DA-D, but doesn't show the transmitter location.

It really is a tight fit with the Evanston station, with a really big problem being the co-channel out west in Rockford, roughly 60 miles away. So far as their transmitter locations are concerned (and I don't know if this actually adds anything) I was able to find this site, which has some WEAW history: http://24.15.236.20/public/xzecom/museum/radiohunt/weaw.htm

 

[radioman148]

1954 Broadcasting Yearbook shows WEAW as a Construction Permit with 500 watts, DA-D, but doesn't show the transmitter location.

It really is a tight fit with the Evanston station, with a really big problem being the co-channel out west in Rockford, roughly 60 miles away. So far as their transmitter locations are concerned (and I don't know if this actually adds anything) I was able to find this site, which has some WEAW history: http://24.15.236.20/public/xzecom/museum/radiohunt/weaw.htm

I found that site too, but it still doesn't tell us if WEAW-AM was directional.

 

[cyberdad]

It really is a tight fit with the Evanston station, with a really big problem being the co-channel out west in Rockford, roughly 60 miles away. 

When I was in high school in Wauconda in the 60's. WEAW and WRRR (Rockford) were almost equal in strength. Neither could overtake the other.

 

[radioman148]

It really is a tight fit with the Evanston station, with a really big problem being the co-channel out west in Rockford, roughly 60 miles away.

When I was in high school in Wauconda in the 60's. WEAW and WRRR (Rockford) were almost equal in strength. Neither could overtake the other.

I just looked at 1330 Rockford (now WNTA's) pattern and they actually have a lobe to the east which is surprising to me.

 

[stormy01]

I don't remember 1330 ever having a transmitter site in Evanston. Where was it located?

Between the North Shore Channel and McDaniel Avenue, just east of McCormick Boulevard and just north of Main Street, Evanston. The area used to be private property, but now is public property known as Harbert Park.

Two shorter towers for AM 1330, maybe 150' max. The two towers were almost north and south of each other, with the south tower slightly more to the SE of the north tower, so the main lobe was probably about 160-170° WEAW most likely did not operate with 5,000 watts (only 500 or 1000 watts) until the transmitter site was moved to Northbrook and a larger parcel of land was secured because there wasn't enough space to "rotate" the towers to a more East-West direction as it is now to maximize the null of the pattern for Rockford. Plus the 4-tower array in Northbrook would have been needed to protect the 1340's in Joliet and Milwaukee with the increased power. I believe the taller FM tower was 240'. I thought the neon sign saying WEAW vertically was on the taller tower. I used to live in Evanston in the 50's and 60's less than a mile east just off of Main St., so of course I saw the station all the time.

For fun, I found this too: http://www.flickr.com/photos/alcue/2733162598/#/photos/alcue/2733162598/lightbox/ I wonder if WEAW-FM operated with 36 kW ERP at first as the letterhead suggests, and then went to 180 kW ERP by using a TPO five times greater?

As for WCPT 820 at night, that coverage map is laughable! Unless there were auroral conditions attenuating CHAM's and WBAP's skywaves, there is no way the red line goes out that far on the end and sides of the pattern, derate at least 5 maybe 10 miles! For example, at Lake-Cook and IL-53 at night the signal is usually torn up really badly by WBAP, and to a lesser extent, CHAM. The R-L coverage map shows that there is supposed to be a "city-grade" signal there. http://radio-locator.com/cgi-bin/pat?call=WCPT&service=AM&status=L&hours=N WCPT's coverage is great in the daytime though, a really good signal just east of Rockford, for example. They hold their own with WBBM 40 kHz down the dial.

 

[Schroedingers Cat]

Sounds like a dogleg three tower array. Once again, anyone have a really old database? My friend Charlie Gustafson passed away, unfortunately. He almost worked for WEAW at one point, but didn't. I don't remember him mentioning the old array. WTAQ/WRDZ is at its third site now. He worked at WTAQ back when it was 500 watts nondirectional. Then WTAQ went to 5000/500 with an oddly configured four tower parallelogram that was nearly in a line and looked like it from the Tollway. Then they moved to the six tower in line next to the Tollway. He told me the story of WIND rebuilding their array. I can't recall exactly what happened. I think it had to do with losing a lease or someone offering a lot of money for the land. WAIT...WCPT 820 lost its lease in Elmhurst I think. That's when it went back to being a daytimer. Too bad they lost that great site, now they have to say Willow Springs once an hour, confusing listeners thinking it's a Chicago station.

 

[Schroedingers Cat]

Stormy, the inner contour on R-L is 2.5 mV/m. City Grade daytime is 5 mV/m. The NIF is 15.5 mV/m, well inside the inner contour shown.

 

[radioman148]

Sounds like a dogleg three tower array. Once again, anyone have a really old database? My friend Charlie Gustafson passed away, unfortunately. He almost worked for WEAW at one point, but didn't. I don't remember him mentioning the old array. WTAQ/WRDZ is at its third site now. He worked at WTAQ back when it was 500 watts nondirectional. Then WTAQ went to 5000/500 with an oddly configured four tower parallelogram that was nearly in a line and looked like it from the Tollway. Then they moved to the six tower in line next to the Tollway. He told me the story of WIND rebuilding their array. I can't recall exactly what happened. I think it had to do with losing a lease or someone offering a lot of money for the land. WAIT...WCPT 820 lost its lease in Elmhurst I think. That's when it went back to being a daytimer. Too bad they lost that great site, now they have to say Willow Springs once an hour, confusing listeners thinking it's a Chicago station.

Schroedinger, do you remember what year WIND rebuilt their towers?

 

[radioman148]

I don't remember 1330 ever having a transmitter site in Evanston. Where was it located?

Between the North Shore Channel and McDaniel Avenue, just east of McCormick Boulevard and just north of Main Street, Evanston. The area used to be private property, but now is public property known as Harbert Park.

Two shorter towers for AM 1330, maybe 150' max. The two towers were almost north and south of each other, with the south tower slightly more to the SE of the north tower, so the main lobe was probably about 160-170° WEAW most likely did not operate with 5,000 watts (only 500 or 1000 watts) until the transmitter site was moved to Northbrook and a larger parcel of land was secured because there wasn't enough space to "rotate" the towers to a more East-West direction as it is now to maximize the null of the pattern for Rockford. Plus the 4-tower array in Northbrook would have been needed to protect the 1340's in Joliet and Milwaukee with the increased power. I believe the taller FM tower was 240'. I thought the neon sign saying WEAW vertically was on the taller tower. I used to live in Evanston in the 50's and 60's less than a mile east just off of Main St., so of course I saw the station all the time.

For fun, I found this too: http://www.flickr.com/photos/alcue/2733162598/#/photos/alcue/2733162598/lightbox/ I wonder if WEAW-FM operated with 36 kW ERP at first as the letterhead suggests, and then went to 180 kW ERP by using a TPO five times greater?

As for WCPT 820 at night, that coverage map is laughable! Unless there were auroral conditions attenuating CHAM's and WBAP's skywaves, there is no way the red line goes out that far on the end and sides of the pattern, derate at least 5 maybe 10 miles! For example, at Lake-Cook and IL-53 at night the signal is usually torn up really badly by WBAP, and to a lesser extent, CHAM. The R-L coverage map shows that there is supposed to be a "city-grade" signal there. http://radio-locator.com/cgi-bin/pat?call=WCPT&service=AM&status=L&hours=N WCPT's coverage is great in the daytime though, a really good signal just east of Rockford, for example. They hold their own with WBBM 40 kHz down the dial.

Thanks for the info Stormy. I do remember the towers just off of Main Street--especially the large FM with the sign. WCGO is just a little bit south of there now.

 

[pianoplayer88key]

So how would I know by listening to a station whether I'm in their NIF? For example, if they were broadcasting an unmodulated carrier, would I not even hear so much of a trace of any modulation audio or the fading (from slightly off-frequency co-channel interference) from stations under it, even if I did the best I could for nulling the local with a directional antenna? And would the noise, even if nulled, be so quiet that even if I cranked the radio's volume up to the max (remember I'm talking about an unmodulated carrier), then switched the radio off, I wouldn't hear any difference? Or if that ultra-strong signal isn't the NIF, approximately what contour might what I described be on, say, a graveyard channel in the northeast USA, or within a couple hundred miles of a class A below 800 kHz across 15 mS/m or better ground right before sunset? (BTW if I position my radio just right I can almost completely null a 50kW class B that's 7 miles from me.)

 

[Schroedingers Cat]

I think WIND rebuilt their array in the late 1970s. I remember riding in the car and seeing no top loading and wondering if I was seeing things, or not seeing things in this case. They moved about 1/4 mile as recall. Same thing with WEAW. Didn't see the top loading.

 

[Schroedingers Cat]

Pianoplayer, you should be able to hear the signal well outside the NIF, since that's 20:1 D/U or 26 dB. With all the other noise, and stations not going to night pattern and such, Class B regionals are often iffy at the NIF now. Class As still pay some attention if some station stays on day power. You will still hear a signal with a dead carrier though it should be 26 dB down or more. With WBAP through a dead carrier on WCPT, you might hear it, since there's not much other interference and WBAP's signal is strong, like 0.775 mV/m 10% of the time and perhaps half that 50% of the time.

 

[stormy01]

Thanks for the info Stormy. I do remember the towers just off of Main Street--especially the large FM with the sign. WCGO is just a little bit south of there now.

You're welcome radioman! Remember too that WNMP/WLTD's omnidirectional tower is still at 2100 Lee St. which is where 1590 operated from until the 4-tower array was built just east of the metropolitan water reclamation plant near McCormick Blvd. and Howard St. The Lee St. tower might still be kept as a backup too and/or used for communication antennas like WOJO's (WEAW-FM) old tower is being used. Before that, WNMP's tower was located on the north side of Oakton near Hartrey Ave., just down the street from the old Rust-Oleum factory! Remember that? Now that's a bit of history on Evanston radio!

 

[radioman148]

Thanks for the info Stormy. I do remember the towers just off of Main Street--especially the large FM with the sign. WCGO is just a little bit south of there now.

You're welcome radioman! Remember too that WNMP/WLTD's omnidirectional tower is still at 2100 Lee St. which is where 1590 operated from until the 4-tower array was built just east of the metropolitan water reclamation plant near McCormick Blvd. and Howard St. The Lee St. tower might still be kept as a backup too and/or used for communication antennas like WOJO's (WEAW-FM) old tower is being used. Before that, WNMP's tower was located on the north side of Oakton near Hartrey Ave., just down the street from the old Rust-Oleum factory! Remember that? Now that's a bit of history on Evanston radio!

Wow--now you're really going back into the depths of my fried brain. ;D

 

[fybush]

Stephen, I know you're really into absolutes and extremes, but NIF doesn't work that way. It's a theoretical concept and highly subject to propagation variations. Even the underlying math behind NIF calculations acknowledges that interference comes and goes: various pieces of the rules examine interference that takes place "at least 10% of the time" and "at least 50% of the time."

You can find the full rules starting at 73.182(k):

http://www.hallikainen.com/FccRules/2011/73/182/

So in the real world, no, a station transmitting only an open carrier won't necessarily give you full quieting 100% of the time at all points within the predicted NIF contour. Depending on whether the station being protected has a properly-functioning ground system and directional array, and whether the other stations on the channel are properly maintained and operating within their licensed parameters, you could get anything from dead full quieting to a fairly noisy signal...and the same is true at plenty of points beyond the predicted NIF contour.

A veteran allocations engineer of my acquaintance typically maps AM stations at night with two sets of contours: calculated NIF, and calculated NIF+50%. The latter figure tends to be a little more relevant to real-world reception conditions. (In the case of WOSU on 820, for instance, that expands the night footprint from the calculated NIF of 11.6 mV/m, which covers most of the central part of Franklin County, to 6 mV/m, which takes the night footprint north to Delaware and southeast to Canal Winchester.)

 

[pianoplayer88key]

Ahh. Well I just did a little experiment with my Tecsun PL-606 (to use the signal strength display), Sony SRF-59 (it sounded cleaner when actually listening to the results, although I didn't record anything for upload) and Panasonic RQ-SW20 (to use its PLL-synthesized local oscillator to generate a test "strong" signal, as the dial-tuned grid dip oscillator I tried using was way too unstable - was drifting a few hundred Hz for no reason at all). Using a test DX target on 1670 (KHPY Moreno Valley), it had an average signal reading of about 27 dBµ on the Tecsun. Tuning the Panasonic to 1220 generated an 87 dBµ carrier (unmodulated) on the Tecsun. I could still hear KHPY underneath it, though, but it was very weak. For some reason it sounded cleaner on the Sony.
Before that, I briefly tested with the grid dip oscillator on a couple other signals (I can tune it pretty much anywhere from about 400 kHz to about 250 MHz, and it puts out a stronger signal than the Panasonic's LO). For example, there were a few that were around the upper 40s to lower 50s dBu without the interference. With the carrier, I could still make out program audio (although the oscillator drift made it difficult to follow) even if the Tecsun was reading into the 90s dBµ. Once it got past 98 dBµ (pegging the meter), though, nothing would break through, not even my strongest local at around 80 dBµ.

Oh... hey Scott... you run that entertaining tower site (wish I could afford a subscription )... a couple months ago I was trying to look through it finding tower sites with development around them, but I'm not sure I found everything there is. Would there by any chance be some source where I could find out where all the tower sites (especially ones that use 50kW) are that have commercial or residential development on top of where their ground radial systems would be? For example... the sites where it might be common to be this close to a tower (even though that 590-KTIE is only 2.5 kW? I did find one spot on Google Maps where 1270 XEAZ is fairly close to some houses, but that one's only 500 watts and compared to what I'm looking for would not be much of a challenge for adjacent-channel DXers.
Are there sites you know of where people (and I don't mean the engineers that work there) live close enough to the towers so that you can literally pick up the station loudly (enough to at least fill a several hundred to couple thousand seat heavily plushly carpeted auditorium, if not, say, Wrigley Field at the time the Cubs win a World Series) on a well-shielded home theater floor-mounted speaker (one of those that's maybe a foot deep, wide and a few feet tall) WITHOUT a diode or an external power source if you maybe short the speaker leads together?

 

[radioman148]

Oh... hey Scott... you run that entertaining tower site (wish I could afford a subscription )... a couple months ago I was trying to look through it finding tower sites with development around them, but I'm not sure I found everything there is. Would there by any chance be some source where I could find out where all the tower sites (especially ones that use 50kW) are that have commercial or residential development on top of where their ground radial systems would be? For example... the sites where it might be common to be this close to a tower (even though that 590-KTIE is only 2.5 kW? I did find one spot on Google Maps where 1270 XEAZ is fairly close to some houses, but that one's only 500 watts and compared to what I'm looking for would not be much of a challenge for adjacent-channel DXers.
Are there sites you know of where people (and I don't mean the engineers that work there) live close enough to the towers so that you can literally pick up the station loudly (enough to at least fill a several hundred to couple thousand seat heavily plushly carpeted auditorium, if not, say, Wrigley Field at the time the Cubs win a World Series) on a well-shielded home theater floor-mounted speaker (one of those that's maybe a foot deep, wide and a few feet tall) WITHOUT a diode or an external power source if you maybe short the speaker leads together?

The WGRB towers in Chicago are in a residential neighborhood completely surrounded by homes. The last time I drove by about 5 years ago there was a lady sunbathing in her backyard about 150 to 200 feet away from the towers.

 

[pianoplayer88key]

The WGRB towers in Chicago are in a residential neighborhood completely surrounded by homes. The last time I drove by about 5 years ago there was a lady sunbathing in her backyard about 150 to 200 feet away from the towers.

Interesting ... but based on transmit power and antenna pattern, still not quite close enough for what I was looking for. (Although, if it was powerful and/or directional enough to still be CLEARLY audible (by general population standards) over 400 miles away at noon in summer, assuming an average ground conductivity under 1 mS/m and a transmit frequency over 1500 kHz, then that distance might be ok. At the weakest, though, it should completely overload a cheap receiver so that it wouldn't hear ANYTHING else, not even an FM station on that tower. )
Also I looked again at that XEAZ map I linked in my earlier post... and while it's only 500 watts, it appears to be less than 8 feet from one of the houses.
Another way to put it... I was basically looking for a location where someone lives where the signal on a pocket portable, using only its built-in ferrite, would actually be STRONGER than what it is with the combination of utility ground, Select-A-Tenna and the PL-606's 4" ferrite from about 305 feet from the nearest active tower of 50kW 1170-KCBQ (in their main 4-tower lobe, ERP ~200kW). There, the PL-606 was overloading so badly that distorted audio was ALWAYS audible, even when the radio would have otherwise been muted, and harmonics were showing up in the FM band. Also, using that combination, I get a stronger signal on 1170 in the daytime (ERP 112.5 kW in my direction, 9.2 miles, conductivity 8 mS/m) than when I was about 7 or 8 feet from 590 KTIE's (2.5kW) center tower. Also I got the same signal level using that setup on 1580 KMIK (skywave @ night) from 300 miles away (ERP ~ 132 kW toward that location about 1/2 mile NE of my house) that I did using only the PL-606's built-in ferrite from 90 feet NW of 5kW 1290-KKDD's center tower.
I guess there's no living quarters in the USA where the signal from an AM is that strong? Or would we be getting into spontaneous inductively-inflicted RF burn territory?

 

[pianoplayer88key]

To get us back on topic... I made a couple recordings of 820 within the past several hours, using the Sony SRF-59.
Here's the first clip recorded around 1am PDT, which has an ID from a Mexican station. And, here's the second clip recorded around 5am PDT, which when I was listening as it was recording thought I heard a hint of part of "WBAP" but listening to the recording I'm not sure. (I also think I may have heard hints of WBAP's programming in the full length clip from which I got the first ID around 1am.) If you want here are full length clips #1 and #2 if anyone wants to try to pick anything out. (They're several minutes long at 56 kbps.)

 

[stormy01]

Oh... hey Scott... you run that entertaining tower site (wish I could afford a subscription )... a couple months ago I was trying to look through it finding tower sites with development around them, but I'm not sure I found everything there is. Would there by any chance be some source where I could find out where all the tower sites (especially ones that use 50kW) are that have commercial or residential development on top of where their ground radial systems would be? For example... the sites where it might be common to be this close to a tower (even though that 590-KTIE is only 2.5 kW? I did find one spot on Google Maps where 1270 XEAZ is fairly close to some houses, but that one's only 500 watts and compared to what I'm looking for would not be much of a challenge for adjacent-channel DXers.
Are there sites you know of where people (and I don't mean the engineers that work there) live close enough to the towers so that you can literally pick up the station loudly (enough to at least fill a several hundred to couple thousand seat heavily plushly carpeted auditorium, if not, say, Wrigley Field at the time the Cubs win a World Series) on a well-shielded home theater floor-mounted speaker (one of those that's maybe a foot deep, wide and a few feet tall) WITHOUT a diode or an external power source if you maybe short the speaker leads together?

WSB 750 Atlanta is in a commercial office park: http://maps.google.com/maps?f=q&hl=en&q=33.84389,+-84.25333+(WSB-AM)&om=1 WCPT 820 (Daytime) transmitter site is in a residential area, on Belmont Ave. in Chicago: http://maps.google.com/maps?f=q&hl=en&q=41.93833,+-87.75139+(WCPT-AM)&om=1