Re: Will WRCA move to the WUNR site?

[PeterH5322@aol.com]

In a message dated 3/3/02 9:05:39 AM, dan.strassberg@att.net writes:

<<
Because WRCA's existing 300' top-loaded towers are so efficient, obtaining an 
equivalent RMS field from the proposed 200' towers at the WUNR site would 
require 10 kW or thereabouts. However, any daytime power higher than that 
might be impossible--especially using a pattern that resembles the one WUNR 
is proposing. On the other hand, there would be five towers at the WUNR site, 
and the consulting engineers might find a way to use that towers create a 
pattern that protects WJDA to the east, WARL to the southwest, and WDER to 
the northeast. The project does look like a challenge for an antenna-system 
designer, though.

>>

WRCA is getting better than 378 mV/m/kW from the 5 kW array ... pretty good 
considering that the two radiators are top loaded to 185 degrees and 5 kW 
stations generally have higher losses than 50 kW stations.

WRCA's proposed 117 degree towers are 240' tall, so WUNR's 200' towers are 
shorter on 1320, more like 97 degrees ... but still respectable.

I'm sure a designer could get more than the class minimum of 281 mV/m/kW from 
those 97 degree towers. Perhaps 300 to 310 mV/m/kW.

Assuming 300 mV/m/kW, that's still 63 percent, on a power basis, of the 
existing site, so it would take 7,900 watts to produce the same field as is 
presently produced by 5,000 watts.

A designer who elected to use WUNR's site as a basis for WRCA would hold 
those WUNR towers fixed and optimize the pattern by letting the field ratio 
and phasing in those towers vary until a solution was found.

Likely, WUNR's south towers would be selected as WRCA's highest-powered 
towers as the field ratio in those WUNR towers are only about 0.2.


New business ...

Lotus' KIRN, which paid big money to Class II-A KBOI to directionalize away 
from Los Angeles, has submitted two applications to move the Tx site to 6 
miles west of Lancaster in the Mojave Desert. The KBOI modifications were 
completed in 1999, I'm told.

No exhibits were provided with the KIRN applications, but from the array 
parameters alone, it can easily be determined that the pattern maximum is 
190.0 degrees.

Los Angeles proper (the main post office) is on a 189.9 degree bearing from 
the proposed Tx site, so the target market is definitely the core of the L.A. 
metro area.

35 kW is proposed, as are six 88 degree towers.

L.A. is 40 miles distant, most of that being through the Coast Range, which 
includes the dreaded San Andreas Fault.

Costa Mesa's 540 was unsuccessful in serving a distant metropolitan area from 
a high desert site, and KIRN isn't likely to do much better, although Costa 
Mesa was 86 miles from Hesperia, and L.A. is less than half that from 
Lancaster.

It is interesting to note that the 1500 application required adjustments to 
the M-3 maps, and some test transmitter work as well, and this was for a site 
well within the local geologic region, whereas the proposed KIRN site is well 
outside the local geologic region.

My info says Lotus is constructing this site for a quick sale, that it has no 
intention of operating the newly constructed facilities, so excellence in 
engineering isn't as likely to be as important as being able to boast of a 
station with a low band position with 35 kW full-time, which purportedly 
"serves" the #2 radio market.

540's phasor was recently offered to a station for which I consulted, and 
that phasor was rejected as it couldn't handle the required 50 kW. However, 
540's phasor was designed for 25 kW, and I's guess 35 kW would be doable.

540's towers are probably also available, and would be about 120 degrees tall 
on 670, a significant improvement over the proposed 88 degree towers, which 
are barely conforming.

And, from a high desert site, one needs all the efficiency one can get.

Saul Levine's high desert flame-thrower folly (540) may be resurrected under 
the guise of KIRN.

The prospective new station owners should be forewarned.

Peter.