• Get involved.
    We want your input!
    Apply for Membership and join the conversations about everything related to broadcasting.

    After we receive your registration, a moderator will review it. After your registration is approved, you will be permitted to post.
    If you use a disposable or false email address, your registration will be rejected.

    After your membership is approved, please take a minute to tell us a little bit about yourself.
    https://www.radiodiscussions.com/forums/introduce-yourself.1088/

    Thanks in advance and have fun!
    RadioDiscussions Administrators

Star 94 Main & Auxiliary, WQXI Tower Sites in Fybush.com on Friday

R

RoddyFreeman

Scott Fybush's Tower Site of the Week will feature the main and auxiliary transmitter sites for WSTR and the WQXI site on Friday (5/7). I was with Scott when Star 94 Chief Engineer Scott Trask showed us the facilities.

One interesting thing at the main Star 94 site, which I had not seen before, is that WSTR's 100,000 watts are sent out by two separate 50,000-watt transmitters and, according to Scott Trask, the two signals are combined as they leave the antenna. As a result, Star almost never uses its auxiliary site on Bishop Street off Northside Drive near Atlantic Station. If something goes wrong, Scott just turns off the problematic transmitter, and listeners over most of the market do not notice any difference. The hill on Bishop Street where the backup site is located has the best view of Atlanta that I've ever seen. Of course, V-103 and B98.5 use the main same tower as Star 94; the facility has a combiner.

Scott then showed us the WQXI site on Cheshire Bridge Road; you actually enter the site from Lenox Road. Scott Trask then met us at the Star studios and showed us the recently-revamped control rooms. Tripp West was manning the main studio; Seacrest was airing.

If you're interested in seeing this, check out www.fybush.com sometime Friday afternoon or evening.
 
RoddyFreeman said:
One interesting thing at the main Star 94 site, which I had not seen before, is that WSTR's 100,000 watts are sent out by two separate 50,000-watt transmitters and, according to Scott Trask, the two signals are combined as they leave the antenna.
Click to expand...

That would be a good trick - and physically impossible.

The 2 transmitters are combined PRIOR to being sent up the tower to the antenna. And no, the transmitters are NOT 50,000 watt transmitters. The article even states they "are a pair of 35 kW Continental 816s".

Is this evidence of your journalistic ability for accuracy of the press?
 
Kabrich said:
The 2 transmitters are combined PRIOR to being sent up the tower to the antenna. And no, the transmitters are NOT 50,000 watt transmitters. The article even states they "are a pair of 35 kW Continental 816s".

Is this evidence of your journalistic ability for accuracy of the press?
Click to expand...

They are in fact free air combined. The 50,000 each is wrong.
 
I'm somewhat of a layman when it comes to really technical things so I don't know what "free air combined" means. But I called Scott Trask (Star's CE) several days following our visit to clarify the 2-transmitter thing. Scott's exact words, and he repeated them twice, were, "The 2 signals combine as they leave the antenna."

As far as two 50,000-watt transmitters, I was obviously wrong although 100,000 watts of power are ultimately transmitted (according to the FCC database) so I made the assumption that each transmitter was 50,000 watts, which is not the case. However, note that I wrote my post before Scott Fybush's article was published. If I had waited until it was posted, I would have been as much an expert as Kabrich, who read the article before displaying his expertise.
 
Any chance that Mr. Trask was talking about his HD signal? One HD strategy is to interlace the elements for the HD carriers with the elements for the analog carrier. It's called "space combining", and would fit what you describe.
 
Doctor_Technical said:
Any chance that Mr. Trask was talking about his HD signal? One HD strategy is to interlace the elements for the HD carriers with the elements for the analog carrier. It's called "space combining", and would fit what you describe.
Click to expand...

No. I'm guessing "free air combined" (posted by grmf above) means combining as they leave the antenna. Hopefully grmf will come back on and clarify.
 
RoddyFreeman said:
Doctor_Technical said:
Any chance that Mr. Trask was talking about his HD signal? One HD strategy is to interlace the elements for the HD carriers with the elements for the analog carrier. It's called "space combining", and would fit what you describe.
Click to expand...

No. I'm guessing "free air combined" (posted by grmf above) means combining as they leave the antenna. Hopefully grmf will come back on and clarify.
Click to expand...

One transmitter feeds the upper panel system through its own run of 6 inch line. The other feeds the lower panel system via another six inch line. The New street antenna can operate with either the upper or lower panel "cold". WSTR Analog is indeed "space" combined in this fashion. With this setup, one transmitter can drop off---but not cause a significant loss of signal. Also, if one panel experiences a problem, the other panel picks up the slack.
 
...and in addition, HGR1290, each 35 KW transmitter is operated at half-power (17 KW each), so in the event of a failure, the remaining transmitter can be kicked up to full 34 KW transmitter-power-output for even more redundancy.

Sweeeeeet.
 
Roddy- Your your journalistic ability appears to be doing OK..... ;D
 
To me, it sounds like the antenna is nothing more than a two-element array.
 
Initially they had a regular combiner controller, which has a warpign cap in one feed. I think they may have upgraded to a trombone line. The problem with many dual feeds is the necessity to have both feedlines exactly the same, so that any expansion or contraction is equal in both. Otherwise you get a varying beam tilt... and it may not be one you want. The one in question is sutprisingly stable.
 
So this works kind of like the old horizontal - vertical systems with a common exciter driving both systems. Is the signal circular? IIRC a lot of the FM’s went with circular antennas to when they upgraded to 100K or 50K in the late 70’s to protect them selves from move ins or becoming a move in and to save on the power bill. My personal experience with circular antennas was good except for ice and wet snow which was an occasional problem in both Louisville and Cincinnati. Management did not believe that the optional antenna heater which was need. We almost always had a snow or ice event during a winter or spring ratings and 50% to 60% foward power due to the high reflected power. I am sure in the Atlanta market no one tries to a save a few bucks on their antenna with the amount of money that is at stake. It sound like 94.1 is doing things correctly facilities wise.
 
Status
This thread has been closed due to inactivity. You can create a new thread to discuss this topic.


Back
Top Bottom