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Re: Fw: NERW 10/1/99--1060, 650/Reply

In a message dated 10/17/99 11:19:49 AM, Dan.Strassberg@worldnet.att.net 


In early fall of 1981, as I recall, WGTR put its full-time plant on the air.

The CP for full-time specified 25 kW-D/2.5 kW-N DA-2 from five 207-degree

sticks, in-line on a 90-degree azimuth, and spaced 100 degrees apart, at the

Sewell St, Ashland, site. The ground system consisted of 240 0.4-wavelenth

radials per tower. Because of protests from KYW (and probably also WBZ),

except maybe for a couple of weeks, the station was never allowed to operate

with more than about half power day or night. A license to cover was never

granted. Today, the array serves WBPS, which is licensed to Dedham and uses

25 kW-D/3.4 kW-N. It is also the proposed site of WRPT's 2 kW DA-D

operation. When John H Garabedian had that array designed, he pulled out all

of the stops, and very presciently had the towers arranged on a due

east-west line--perhaps in anticipation of the final breakdown of the Class

IA channels. Because of the engineering decisions that were made, the array

is well suited to both WBPS and WRPT.



Interesting you should mention WBPS, Dan. I was going to ask you how that 
array came about.

On 890, the inter-tower spacing is uneven: 1-2: 84.0 degrees, 2-3: 83.0 
degrees, 3-4: 84.0 degrees and 4-5: 83.9 degrees.

The night field ratios are somewhat unconventional: 25-percent, 70-percent, 
100-percent, 70-percent and 25-percent, roughly (but the pattern shape looks 
very nice).

And the phasings are also about what one might expect for the spacing: -100 
degrees, +130 degrees, 0 degrees, -130 degrees and +100 degrees, roughly.

If this array is difficult to tune, it might be from the shorter than normal 
inter-tower spacing, or the somewhat unconventional field ratios.

Certainly, the ground system appears to be good, and there is nothing wrong 
with 173.6 degree towers.

Hell, KFI, a Class I-A only has a 173 degree tower. And I'd bet KFI's ground 
system is nowhere near as good as is WBPS's. Especially now that an 
industrial building has been constructed on KFI's formerly "virgin" site 
(there appeard to be piers for a DA at KFI's site when I last visited it in 
the late 1970s ... perhaps piers for the previously co-owned KECA, when it 
was on 1430).

I like the idea of 200+ degree towers on 1060 (but as you know, I always like 
the idea of 200 degree towers).

BTW, the inter-tower spacing on 1060 would be about 100 degrees on the money, 
and that should make for a quite nice, stable array. Particularly with a 
0.4-wave gound system.