50000 Watt Fulltime Class Bs That Were Class IIIs

[Schroedingers Cat]

It's been two decades or so since the first Class III Regional stations in the US have been allowed 50000 watts and lumped together with Class B stations on Clear Channels. While many stations have increased DAY power to 50000 watts, only four managed to get to 50000 watts at night.

What are the characteristics of those stations? They are very OLD stations at the edge of the country or next to the ocean. They had night patterns that already interfered significantly with MANY stations. The Ratchet Clause allowed them to increase all the way to 50000 watts night because they didn't have to protect those stations to 25% RSS limitation of well protected former Class IIIs. Stations that didn't interfere with many cochannel stations tend to be closedly spaced to other well protected stations. These are often limited to 15000 to 25000 watts at night by the old Class III-As that are close by. The standard pattern minimum computed for a 50000 watt station cannot be less than 70.7 mV/m @ 1 kilometer horizontal inverse field. If this or the field above horizontal doesn't already enter into the old Class III-A or III-B 50% RSS or 25% RSS calculation of other stations, it usually cannot be 50000 watts at night. In some cases, other stations can be eliminated or upgraded to allow more interference from other stations. This has mainly been done for day pattern considerations or former Class II/Class Bs. Class B/Class II Clear Channel stations often already had high power at night.

What are those four lucky Class III stations that ended up as 50000 watts day and night?

580 KMJ Fresno, CA
950 KJR Seattle, WA
950 WWJ Detroit, MI
1270 WXYT Detroit, MI

 

[Schroedingers Cat]

I'm sorry. I intended to put this in the DX and Reception Discussion Board. But the discussion is relvant to WIND and WGRB and why they are not 50000 watts nighttime.

WYLL 1160 upgraded WHBY 1150 Kimberly, WI to 25000 watts nighttime to get to 50000 watts nighttime, but it is a Clear Channel Class B. Oddly, this was a greater obstacle than KSL. They also substituted a Canadian allotment.

 

[dave73]

I'm not sure why WIND & WGRB aren't at 50kw at night. I believe that WIND doesn't need the extra power, as it manages to reach Milwaukee both day & night from their site in Griffith Indiana at 5kw (I know this for a fact, because I have tuned into 560 boht day & night when in Milwaukee, & get no interference). If any of the 2 would benefit from going 50kw (if it were possible) would be WGRB much more than WIND, since WGRB is at 1390, & 5kw doesn't go as far at the higher end of the dial.

Now for the 4 stations you mentioned that got to go 50kw at night, WXYT was one I got a faint signal at night in Gary Indiana until about December 2002 or 2003, when WWCA Gary Indiana signed back on. I live that close to both the WIND & WWCA tower sites that I don't get anything else on 560 & 1270, & usually get bleedover on 550 & 570 from WIND & 1260 & 1280 from WWCA.

 

[Schroedingers Cat]

One problem with frequencies like 1220, 1250, 1330, 1350, 1390, 1410, 1440, 1460, 1480, and 1500, is that they are usually jammed in by Class IVs/Class Cs in the daytime. For WGRB 1390, WRJN and WSJM come to mind immediately and 1380 in South Beloit. They are all protected to the 0.5 mV/m from further 0.25 mV/m overlap in the daytime. I will have to look further for 1390 night restrictions, but WIND can't increase at night toward WEBC 560 Duluth and probably WSAU 550 in Wisconsin day or night, or WKRC 550 day.

On further investigation, WRIG 1390 Schofield, WI would limit WGRB from increasing.