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antenna lift

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SolarMax
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antenna lift

Post by SolarMax » Tue Jun 16, 2020 4:05 pm

For those fascinated by such things, there might be a chopper doing antenna lift Saturday 6/20 on the 8 Mile/Meyers tower, around 8am.



k8jd
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Re: antenna lift

Post by k8jd » Tue Jun 16, 2020 4:11 pm

They must be running out of room on the old WWJ tower !



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SolarMax
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Re: antenna lift

Post by SolarMax » Tue Jun 16, 2020 4:45 pm

There is no "old WWJ tower" there, not for many years. A couple of the stations on the Big tower have been on their repack channels using a temporary "community" side-mount. Obsolete antennas on the candelabra will be removed and their replacements mounted. After a testing period, they'll be put into permanent service.,



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Turkeytop
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Re: antenna lift

Post by Turkeytop » Tue Jun 16, 2020 9:51 pm

I'm the kind of geek, interested in those kinds of events. But it's off limits for me because the Canada/US border is closed.



statmanmi
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WTOM Cheboygan Re: antenna lift

Post by statmanmi » Thu Aug 06, 2020 3:10 am

Perhaps someone will know of newer information, but....

The most recent FCC filings for WTOM-TV Cheboygan notes in at least 3 places, “Helicopter pick scheduled for 8/9/20.”

I’m recalling perceiving or reading in other filings or places that the old analog RF4 antenna will come down, with the new Dielectric RF16 one going up in its place.

Cheers! ~~ Statmanmi



km1125
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Re: antenna lift

Post by km1125 » Thu Aug 06, 2020 8:16 am

SolarMax wrote:
Tue Jun 16, 2020 4:45 pm
There is no "old WWJ tower" there, not for many years. A couple of the stations on the Big tower have been on their repack channels using a temporary "community" side-mount. Obsolete antennas on the candelabra will be removed and their replacements mounted. After a testing period, they'll be put into permanent service.,
Offhand, do you know which stations these are? Curious if any reception is going to improve after they're done.



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Plate Cap
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Re: WTOM Cheboygan Re: antenna lift

Post by Plate Cap » Thu Aug 06, 2020 10:35 am

statmanmi wrote:
Thu Aug 06, 2020 3:10 am


I’m recalling perceiving or reading in other filings or places that the old analog RF4 antenna will come down, with the new Dielectric RF16 one going up in its place.
The channel 4 batwing came off the pole a long, long time ago....right after the DTV transition. I have had one of the bays behind my barn for several years. I was going to make a mailbox support out of it, but modifying it to the height required by the USPS would render it unrecognizable as to it's original purpose.

The remaining pylon supported 97.7 for a while.


The box that many broadcasters won’t look outside of was made in 1969 and hasn’t changed significantly since.

CK-722
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Re: WTOM Cheboygan Re: antenna lift

Post by CK-722 » Thu Aug 06, 2020 1:19 pm

Plate Cap wrote:
Thu Aug 06, 2020 10:35 am
statmanmi wrote:
Thu Aug 06, 2020 3:10 am


I’m recalling perceiving or reading in other filings or places that the old analog RF4 antenna will come down, with the new Dielectric RF16 one going up in its place.
The channel 4 batwing came off the pole a long, long time ago....right after the DTV transition. I have had one of the bays behind my barn for several years. I was going to make a mailbox support out of it, but modifying it to the height required by the USPS would render it unrecognizable as to it's original purpose.

The remaining pylon supported 97.7 for a while.
Despite popular belief, Horizontal only polarized VHF superurnstile transmitting antennas are NOT nondirectional. The pattern is tetrafolar, like a four leaf clover. The four nulls at 45 degrees from perpendicular to the reflectors are a little over 2 dB less than the four perpendicular lobes. What I can't figure out is if VHF-Low stations using such an antenna were able to use the average polar gain or the maximum polar gain. If they used AVERAGE gain, there would be a 1 dB gain in the maxima and 1 dB loss in the nulls. WJIM-FM 97.5 Lansing used such an antenna until they moved to Pine Tree Rd. For decades, I thought the antenna by Frandor was the AUX antenna for WJIM-TV, and perhaps it was also diplexed for this. In any event, VHF Low Batwings have been used much further up the FM Band than 97.5 MHz. I don't know if any other modifications were necessary to do this.

Link showing typical superturnstile Horizontal Pattern. Use the pdf link at the bottom to view the actual H Pattern.

https://www.alandickbroadcast.com/vhf-s ... e-antenna/

If the average gain were used determining the TV ERP, the actual ERP was about 125 kW Maximum and 80 kW Minimum. If it were used for a 100 kW FM DA, the maxima would be 100 kW, but the minima would be about 64 kW. Unless the Batwing Bays were made to be circularly polarized, you could go old school and have a separate 64 kW ERP Vertically Polarized antenna. These would be useful in situations where you need maximum gain in more than one direction, and a shallow null or nulls in other directions.


Is THAT where they got the idea for the 486-SX?

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Rich F.
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Re: WTOM Cheboygan Re: antenna lift

Post by Rich F. » Fri Aug 07, 2020 6:02 am

CK-722 wrote:
Thu Aug 06, 2020 1:19 pm
... What I can't figure out is if VHF-Low stations using such an antenna were able to use the average polar gain or the maximum polar gain. ...
All VHF and UHF TV broadcast stations not required by the FCC to use a directional radiation pattern were/are licensed to use the RMS gain of their antenna, as determined by its manufacturer and found in its published specifications.

BTW, the departure from perfect circularity of the h-plane radiation pattern of a batwing/supertunstile TV transmit antenna is a lot less than that of a typical "circularly polarized" FM broadcast antenna mounted on the leg or face of a supporting tower structure.



k8jd
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Re: WTOM Cheboygan Re: antenna lift

Post by k8jd » Sat Aug 15, 2020 2:34 pm

Plate Cap wrote:
Thu Aug 06, 2020 10:35 am
statmanmi wrote:
Thu Aug 06, 2020 3:10 am
shock: :o

The channel 4 batwing came off the pole a long, long time ago....right after the DTV transition. I have had one of the bays behind my barn for several years. I was going to make a mailbox support out of it, but modifying it to the height required by the USPS would render it unrecognizable as to it's original purpose.
.
[/quote}
That Channel 4 antenna could be used For Amateur Radio If we ever get thet piece of 72-76 MHz like some other countries.
Save It !!!



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SolarMax
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Re: WTOM Cheboygan Re: antenna lift

Post by SolarMax » Sat Aug 15, 2020 6:06 pm

k8jd wrote:
Sat Aug 15, 2020 2:34 pm
That Channel 4 antenna could be used For Amateur Radio If we ever get thet piece of 72-76 MHz like some other countries.
Save It !!!
That is not ever going to happen. Scrap it.



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MWmetalhead
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Re: antenna lift

Post by MWmetalhead » Sun Aug 16, 2020 6:31 pm

BTW, the departure from perfect circularity of the h-plane radiation pattern of a batwing/supertunstile TV transmit antenna is a lot less than that of a typical "circularly polarized" FM broadcast antenna mounted on the leg or face of a supporting tower structure.
That certainly reminds me of the very noticeable null in 93.7 WBCT's signal in & just east of Battle Creek.

Actual signal strength in the car is nowhere close to predicted strength. Instead of city grade reception (as predicted), the actual reception is more indicative of a 50 dBu to at most 54 dBu signal (F 50, 50).

Their signal also underachieves a bit in the Lansing area.


Rock 95.5 in Chicago is the worst sounding major market rock station in the history of corporate radio.

CK-722
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Re: antenna lift

Post by CK-722 » Sun Aug 16, 2020 7:07 pm

MWmetalhead wrote:
Sun Aug 16, 2020 6:31 pm
BTW, the departure from perfect circularity of the h-plane radiation pattern of a batwing/supertunstile TV transmit antenna is a lot less than that of a typical "circularly polarized" FM broadcast antenna mounted on the leg or face of a supporting tower structure.
That certainly reminds me of the very noticeable null in 93.7 WBCT's signal in & just east of Battle Creek.

Actual signal strength in the car is nowhere close to predicted strength. Instead of city grade reception (as predicted), the actual reception is more indicative of a 50 dBu to at most 54 dBu signal (F 50, 50).

Their signal also underachieves a bit in the Lansing area.
What are you using to determine the field strength?

Maybe Rich can chime in on this.

I don't doubt that they long ago gave up on 320 kW WBCT "The Beast" serving Lansing. I would imagine that the actual pattern favors Grand Rapids and Kalamazoo. Realize that the actual field in those directions could well exceed 320 kW, as the 320 kW is the average, because it is licensed nondirectional. WGRD had an application for 30 kW DA from Dias Hill back in the late 1970s to around 1980. J.J. Duling said they were "worried about Kalamazoo". Recently, it occurred to me what what he was told meant, and why they didn't go DA. The DA would have pulled in for an arc from the minimum which couldn't exceed 2 dB per 10 degrees. Often this null pull in arc extends even beyond the theoretical 20 degrees either side of the azimuth toward WLUP (now WCKL) required. This arc probably involved the Kalamazoo area. So in retrospect, they could be licensed nondirectional and actually exceed 13 kW toward Kalamazoo, and presumably Grand Rapids. It turns out that they were in the 50 kW short spaced zone toward WKCQ and WJLB, 80 miles and 125 miles respectively, under the old Section 73.213 in place at the time. That is why you see many 50 kW Class B cochannel and first adjacent channels so authorized at barely 124.5 and 79.5 miles. That was also the rule which allowed WLAV-FM to be 50 kW nondirectional from the old tower site.


Is THAT where they got the idea for the 486-SX?

Same (x, y, z), different (t)

Your bullet missed my trial balloon.

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MWmetalhead
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Re: antenna lift

Post by MWmetalhead » Sun Aug 16, 2020 7:49 pm

I'm using my ears and the amount of scratchiness coming thru the speakers to estimate field strength. :)

Based on anecdotal observation, I agree B93's pattern favors GR and Kalamazoo.

WGRD's present day signal in the Kalamazoo area is mediocre at best. Comes in decently on the the north end of town; a good deal of picket fencing pretty much everywhere else. It's almost non-existent by the time one reaches Schoolcraft.

Their signal seems to favor northbound areas. Heading north, their usable range seems to extend a good ten miles farther.

In that southerly direction toward K'zoo, WGRD definitely performs more like a Class B1 than a Class B facility. WCSG, which does use a directional antenna from nearly the same height as WGRD's non-directional antenna, delivers a noticeably stronger signal to Kalamazoo and Portage than WGRD.


Rock 95.5 in Chicago is the worst sounding major market rock station in the history of corporate radio.

CK-722
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Re: antenna lift

Post by CK-722 » Sun Aug 16, 2020 8:22 pm

Due to the dearth of FM Top 40 except WKFR Battle Creek (and AM at Night besides WKMI, and except for WLS and WOWO) choices in Kalamazoo in the late 1970s, WGRD-FM did very well in Kalamazoo back then, even with a relatively weaker signal. It was very tightly formatted. FMs from adjacent markets did well in those days before there were so many drop ins. No doubt due to the poor real conductivity around Grand Rapids, the Daytimers, and the Class IVs with 250 watts, once full-time and then Night, Grand Rapids dropped in an inordinate number of FMs for market size at the time, and before around 1962 when the rules changed to Distance Separation Requirements, an increase in protected service contours for Class Bs from 60 dBu to 54 dBu, and contour overlap like Canada still has and NCE-FM in the US has. That is why so many FMs in Grand Rapids, Holland, etc., are short spaced. This is now becoming a problem, like with WLAV-FM, especially to Chicago and Milwaukee area stations, where overlap was once completely excluded over Lake Michigan, and because of relocations due to tower and land sales.

Daytimers and Class IVs and Fulltimers with poor signals were usually most likely to file for FMs first. In markets with good full-time signals, owners often delayed applying for FMs. Then when the rules changed, many of them no longer had the option to apply for new channels, as none fit in. The existing stations were grandfathered, and short spaced stations still had the option to upgrade, often with maximum facilities for their Class, under earlier rules. Of course, these had now prohibited overlaps, but had solid near full Class coverage. Remember also that many stations had FM antennas on short AM towers, but still were allowed to upgrade to full facilities under ever changing rules.


Is THAT where they got the idea for the 486-SX?

Same (x, y, z), different (t)

Your bullet missed my trial balloon.

RTN Price. Not guaranteed. As of 12:30, 157.71 Down 0.22.

Artificial Intelligence is a Child that needs a Parent to guide it through.

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