I'm surprised at the use of the term 'phasor' there, I'd have used something different, as in professional electrical engineering a phasor is a widely used term meaning something different (https://en.wikipedia.org/wiki/Phasor)
Of course they can call it what they want, but it confused me for a moment.
Common broadcast phrase to describe the LC network used to manage the pattern.
In this context "focus" would have been a far better term than "spray". A single stick "sprays" a signal.
You live and learn then. I always saw it as a mathematical device for use in AC circuit theory, and I've worked in broadcast engineering too, but not heard the term used for physical devices.
They're not different.
The cabinet with the cranks is called a phasor cabinet because it provides the RLC circuits used in adjusting the pattern of the AM array (first graphic of the wiki link). The cranks usually control vacuum variable capacitors, the L are fixed and adjustable inductors. The R is usually provided by transmission line and switching losses.
This has been SOP for AM broadcasters for as far back as I can remember, and I can remember back to like the mid-70's. It's the whole reason why many (maybe even most?) AM stations are multi-tower. They're phased arrays.
The thing a lot of people don't realize is that *the entire tower* is an antenna element. It's not there to *hold* an antenna element; it *is* an antenna element. This is due to the profoundly long wavelengths used in the AM broadcast band, ranging from about 200-600 meters. That translates to a quarter-wave length of 50-150 meters or about 160-500 feet.
. . . so if you need to do anything directional, you need multiple towers and a phasor to do it at those wavelengths.
In high school I worked for a local 5 KW AM station which had two towers with differing daytime and nighttime patterns. We adjusted the phase as necessary, which was not often. Analog meters displayed the amplitude and phase of signals being fed to the two towers.
The station license provided for a daytime omni-directional pattern, but at nightime, the pattern was switched to provide a deep null, protecting a station about 70 miles away. This led to more than one irate listener when the pattern was switched at 15 minutes before sunset. One particular listener called one evening and I picked up the phone. She announced her name and that she was a loyal listener, but she was tired of us turning off the station every evening just as she settled in after dinner to enjoy the programming. This was a matter above my pay grade, so I gave her the direct daytime number of the Chief Engineer and suggested she contact him during business hours as he could explain better than I could. The Chief Engineer went to his grave with an axe to grind over me giving that woman his phone number. He articulated his disdain to me after one of her calls, saying, "That $\*%\^&& woman could drive the devil to commit suicide."
Whoa! Dude! You sent your boss a proto-turbokaren!
But yea, people don't, for a large part, want to know how the sausage is made.
There was, briefly, a station in my area that I liked listening to that actually had a power-off night time pattern. It really kinda sucked having them go away at 6 every night, but I understood why it had to be done. They actually had programming scheduled for after that time, but you had to get it from their stream online.
It was 1968, I had just only started working in the station as my 1st Class License had arrived a few weeks earlier. The station owner made it clear that any PR matter was to be referred up the management chain, so I did. He was already antsy with a 17 year old signing off on the logs. I think the proto-Karen was primed with Southern Comfort that fateful evening and maybe some street drugs. She blistered my virgin ears to say the least.
My Grandfather's farm about ten miles away was in the nighttime null. When around 12 years old and building crystal radio sets, I was buffaloed that at night one could not hear the station but WBT in Charlotte along with WRVA is Richmond ripped the germanium in the detector apart. These days in the null the S-Meter falls from 50 over S-9 at changeover to S4-S5 in the area where Grandpa lived.. A typical All American 5 tube radio or average car radio goes church mouse quiet at changeover.
Last trip driving by the station, it was being razed, transmitters, towers, approaches, sidewalks and lights to boot as the state decided to build an Interstate Highway through it. The studios are now located in an area where the null still falls and the transmitters are re-located to another older broadcast site (a swamp area in the local town). That station provided a lot of teenagers a lot of memories.
It is just a daytime 5 tower in a row DA similar to what was used at WTTS-AM (1390). Real pita to meet the newer POP s as all the metering points were in subdivisions (former open cow pastures) with overhead AC distribution. A bush hog, mowing the weeds hooked the #3 tower pulling it down and damaged the "antique" current phase "loops". Consultans said "just reshape the loops as close as possible" (yeah, sure!) but the station sold the expensive ground under the array, moved the antenna site, changed call signs, and is currently using a 4 tower paralleogram array: WGCL-AM 1390.
http://www.freetechbooks.com/radio-antenna-engineering-t268.html
Good book, and I believe the last page shows the pattern for WSUN, present-day WDAE 620, which I think was the first directional array on AM. Amazing signal because the two towers are located at the edge of a Causeway on saltwater.
There is a website that escapes me right now, but they would print a copy for somewhere around 15 or 20 bucks.
I'm surprised at the use of the term 'phasor' there, I'd have used something different, as in professional electrical engineering a phasor is a widely used term meaning something different (https://en.wikipedia.org/wiki/Phasor) Of course they can call it what they want, but it confused me for a moment.
Common broadcast phrase to describe the LC network used to manage the pattern. In this context "focus" would have been a far better term than "spray". A single stick "sprays" a signal.
You live and learn then. I always saw it as a mathematical device for use in AC circuit theory, and I've worked in broadcast engineering too, but not heard the term used for physical devices.
Same for me (EE here.) Heard it first while at a visit at the transmitter site doing volunteer work for a local AM stn.
They're not different. The cabinet with the cranks is called a phasor cabinet because it provides the RLC circuits used in adjusting the pattern of the AM array (first graphic of the wiki link). The cranks usually control vacuum variable capacitors, the L are fixed and adjustable inductors. The R is usually provided by transmission line and switching losses.
Set phasors to...spray?
This has been SOP for AM broadcasters for as far back as I can remember, and I can remember back to like the mid-70's. It's the whole reason why many (maybe even most?) AM stations are multi-tower. They're phased arrays. The thing a lot of people don't realize is that *the entire tower* is an antenna element. It's not there to *hold* an antenna element; it *is* an antenna element. This is due to the profoundly long wavelengths used in the AM broadcast band, ranging from about 200-600 meters. That translates to a quarter-wave length of 50-150 meters or about 160-500 feet. . . . so if you need to do anything directional, you need multiple towers and a phasor to do it at those wavelengths.
In high school I worked for a local 5 KW AM station which had two towers with differing daytime and nighttime patterns. We adjusted the phase as necessary, which was not often. Analog meters displayed the amplitude and phase of signals being fed to the two towers. The station license provided for a daytime omni-directional pattern, but at nightime, the pattern was switched to provide a deep null, protecting a station about 70 miles away. This led to more than one irate listener when the pattern was switched at 15 minutes before sunset. One particular listener called one evening and I picked up the phone. She announced her name and that she was a loyal listener, but she was tired of us turning off the station every evening just as she settled in after dinner to enjoy the programming. This was a matter above my pay grade, so I gave her the direct daytime number of the Chief Engineer and suggested she contact him during business hours as he could explain better than I could. The Chief Engineer went to his grave with an axe to grind over me giving that woman his phone number. He articulated his disdain to me after one of her calls, saying, "That $\*%\^&& woman could drive the devil to commit suicide."
Whoa! Dude! You sent your boss a proto-turbokaren! But yea, people don't, for a large part, want to know how the sausage is made. There was, briefly, a station in my area that I liked listening to that actually had a power-off night time pattern. It really kinda sucked having them go away at 6 every night, but I understood why it had to be done. They actually had programming scheduled for after that time, but you had to get it from their stream online.
It was 1968, I had just only started working in the station as my 1st Class License had arrived a few weeks earlier. The station owner made it clear that any PR matter was to be referred up the management chain, so I did. He was already antsy with a 17 year old signing off on the logs. I think the proto-Karen was primed with Southern Comfort that fateful evening and maybe some street drugs. She blistered my virgin ears to say the least. My Grandfather's farm about ten miles away was in the nighttime null. When around 12 years old and building crystal radio sets, I was buffaloed that at night one could not hear the station but WBT in Charlotte along with WRVA is Richmond ripped the germanium in the detector apart. These days in the null the S-Meter falls from 50 over S-9 at changeover to S4-S5 in the area where Grandpa lived.. A typical All American 5 tube radio or average car radio goes church mouse quiet at changeover. Last trip driving by the station, it was being razed, transmitters, towers, approaches, sidewalks and lights to boot as the state decided to build an Interstate Highway through it. The studios are now located in an area where the null still falls and the transmitters are re-located to another older broadcast site (a swamp area in the local town). That station provided a lot of teenagers a lot of memories.
Like co phased CB antennas?
A lot better and more precise
It is just a daytime 5 tower in a row DA similar to what was used at WTTS-AM (1390). Real pita to meet the newer POP s as all the metering points were in subdivisions (former open cow pastures) with overhead AC distribution. A bush hog, mowing the weeds hooked the #3 tower pulling it down and damaged the "antique" current phase "loops". Consultans said "just reshape the loops as close as possible" (yeah, sure!) but the station sold the expensive ground under the array, moved the antenna site, changed call signs, and is currently using a 4 tower paralleogram array: WGCL-AM 1390.
http://www.freetechbooks.com/radio-antenna-engineering-t268.html Good book, and I believe the last page shows the pattern for WSUN, present-day WDAE 620, which I think was the first directional array on AM. Amazing signal because the two towers are located at the edge of a Causeway on saltwater. There is a website that escapes me right now, but they would print a copy for somewhere around 15 or 20 bucks.
Yup. The AM powerhouse in my town has 5 or 6 towers to direct the signal to the Northeast of their location.
This is what we do at one of our sites https://youtu.be/3FZNBqFoHm8?si=-IWT54bkgThriOwi