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Strongest Skywave Signal(s)?

What is the strongest skywave signal(s) that you normally receive, particularly from a station(s) that you can hear no trace of at midday in June without skywave? A couple of comparisons between CFZM and CJBC skywave signals got me thinking about this. For me, it would have to be WBZ 1030. They tend to register as high as the lower 60s dBu strength at over 600 miles with HD locks that can last up to a minute at a time here in Vermilion, OH. I believe this is attributed to their directional signal which effectively sends more juice to the west.
 
WBZ 1030 is better than 2 of our local stations in terms of strength at night. Not there during the day at all except from the end of November to the end of January.
 
Here in Columbus, WMVP and WBZ are consistently the strongest every night. KMOX is not far behind. WGN is in the conversation when not being pummeled by WOR's IBOC.
 
The strongest skywaves at night usually heard in the daytime are in the 50 uV/m groundwave range at the lower half of the AM Broadcast Band. You won't hear them if there is a cochannel station. Good examples of ones that can't be heard are WMVP 1000, blocked out by WCCD in the Cleveland, Ohio area, and WCKY 1530, blocked out by WLCO in the Flint and Detroit areas of Michigan. Both WMVP and WCKY have skywaves that reach a maximum close to 10 mV/m in those areas. WOWO would reach these levels when it was 50 kW at night. You could hear these occasionally with a simple crystal radio with a Germanium diode and a 100 foot long wire antenna. Note that the strongest skywaves are almost always directional.
 
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WBZ has always been among the strongest at my location in the northern Chicago suburbs. WSM is also in the conversation. WWL used to be, but they are not as strong in recent years as they once were.
 
Besides WBZ, KYW and WRVA are some other directionals with big skywaves, though not as strong as WMVP and WCKY at their peak. Old skywave curves would put the nondirectional stations about 500 miles away at around 2 mV/m 10%, but the directional are probably around 3 mV/m 10% skywave at that distance. Close in Class I-As 150-300 miles away have considerably less than maximum horizontal inverse field reflecting toward your receiver location. Often these are no stronger than the stations further away.

Near the Straits of Mackinac, WWJ at 50 kW and WFDF before sunset at 50 kW are often peaking near 10 mV/m. Even at 25 kW night, WFDF is one of the strongest skywaves, exceeding WJR and the Chicago Class As. Both WWJ and WFDF are very listenable at night in an electrically quiet location when there is not a lot of cochannel interference. When there is winter daytime skywave, WLQV also comes in quite strong all day long. The daytime skywave curves are considerably lower than the nighttime, so you might be talking around 200-500 uV/m at peak in the daytime.
 
KEX is usually strong, as is KGO and KSL, here in Western WA.

-crainbebo
 
Let's see.
Not audible during the day. Strong at night.
WTAM/1100 Cleveland
KMOX/1120 St. Louis
CJBC/860
WBZ/1030 Boston - Not as good as the old days.
WRVA/1140 Richmond
WLAC/1510 Nashville
I guess I should also include WCBS/880 NYC

Weak during the day. Strong at night.
WJR/760 Detroit
WSM/650 Nashville
With a couple of my receivers I can hear these guys during the day, so I put them in the weakday category. WMVP/1000 Chicago & WBBM and WGN, although WGN get pummled by WLW overspray.
 
... Near the Straits of Mackinac, WWJ at 50 kW and WFDF before sunset at 50 kW are often peaking near 10 mV/m. Even at 25 kW night, WFDF is one of the strongest skywaves, exceeding WJR and the Chicago Class As. ...

True, but for added perspective...

The nighttime skywave fields from directional arrays such as used by WWJ and WFDF can be greater at some azimuth and elevation angles than produced by a transmitter of the same output power using a single (omnidirectional) radiator.

However Class A WJR Detroit, and the Chicago (and many other) Class As provide useful nighttime skywave service to far greater coverage areas with far greater population counts than do WWJ and WFDF.
 
Does WBZ's IBOC really spatter on KDKA in Pittsburg? or around it

In another (now unsearchable) thread, someone mentioned the noise floor rising on 1020 KDKA from WBZ's I-BLOCK at night only 30 miles from KDKA. Similar situation was reported with WHAS 840's noise floor rising as close as 30 miles away from WHAS from WCCO 830's I-BLOCK.
 
Far northwest suburbs of Chicago... I'd probably give it to KXEL. WSM, WLW, WCCO, and WBZ also in the mix. "Honorable mention to WMBD for skywave on a "regional" channel.
 
Lately I'm getting a strong nighttime skywave from "News 1310" out of Ottawa, which is also a "regional" channel. They apparently have 50 kW but it's not supposed to be aimed at Chicago during the nighttime hours...
 
Lately I'm getting a strong nighttime skywave from "News 1310" out of Ottawa, which is also a "regional" channel. They apparently have 50 kW but it's not supposed to be aimed at Chicago during the nighttime hours...

When I lived in south east Iowa, I found that 1310 frequently made it in at a very strong level. Back in 1987 I remember hearing top 40 rock on them. Then in the mid 90's I was south on Highway 61 in north east Missouri, coming back from Hannibal. They were in like a local until 5 minutes south of Keokuk, where their local 1310 finally took over. I could still faintly here Ottawa within sight of the towers of the KOKX, Keokuk
 
Houston, used to be WLW. A regular daytime skywave winter signal, with no trace in the summer. Then we got a local 700. Dallas - used to get KOA skywave midday in winter, very rarely in the summer. Then a local 850 signed on. Port Orange, FL - WSB receivable winter skywave midday, not in the summer. Daytona Beach Shores, however, was all groundwave conductivity with multiple 1000 mile plus reception such as most NYC clears. I credit the barrier island made out of salty sand, saturated with water a couple of feet down.
I have done similar stuff in Galveston on the beach. But all that would be classified groundwave. As would my reception in Lubbock, TX of clears 1000 miles away. High ground conductivity, so it was ground wave.
 
CIWW 1310 Ottawa is the station you are hearing. They may be stuck on day pattern.

Canada has allowed 50000 watts on Regional Channels for probably 40 years or more. First it was 10000 watts, and later, 50000 watts.
 
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...As would my reception in Lubbock, TX of clears 1000 miles away. High ground conductivity, so it was ground wave.

According to calculations, even for a 540 kHz DA with 400 kW of radiated power and 30 mS/m earth conductivity, the maximum groundwave field 1,000 miles downrange would be about 4 µV/m.

So more likely a useful daytime MW signal received at such distances would be skywave.
 
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