Ones that can explain it well are very rare. You have no idea the prep and writing that goes into any of my videos. So, Mike explaining on the fly is pretty good.
I always wanted to get into broadcasting but never had an avenue in so I went into the public safety radio side. A lot of the job is similar to keeping a station on the air, just the RF power levels, etc. are not the same. I love antenna systems and especially AM DAs. I even met and chatted with Jack Layton on the ham bands, one of the authorities on directional antennas.
The DX-50 is an amazingly reliable transmitter. I once had to 'shotgun' all the blue capacitors Mike was showing us that filter the power modules when I noticed some of them bloating. Another mod we had to do on the DX-50 was very simple: we swapped the red & green LEDs for the local/remote switch. Normally the transmitter is in "remote" mode, but the LED was red as the Harris default. Once we didn't catch that it was in "local" with a green LED and went back to Hollywood. Naturally, there was a power failure that afternoon, and we couldn't turn the transmitter back on remotely, so had to spend 2 hours driving back to the site just to turn the transmitter back on. So we reversed the LEDs, and before leaving, we installed a big red light at the front door that would go on if we left the building with either transmitter in "local" mode. That saved us a lot of trouble over the years because a single red LED really stands out on a panel of all normally green ones.
50kw from such a small transmitter. I remember the hughe 50kw broadcast AM transmitters with huge final tubes. My Dad used to be a radio engineer at WABC and then WHN in NYC.
Nice to see a Belar modulation monitor continuing to serve. I first encountered one in 1969, at KQV (1410, 5 Kw DA-2 five towers) in Pittsburgh, Pennsylvania. Classy transmitter site-nothing like all that silver-plated coils and copper tubing to drive corporate accounting crazy. “Wait, you need HOW MUCH silver out there? Can’t you just use aluminum wire?” With the building elevated like that in the near field of the antennas, there’s nothing resembling “ground” inside. Thanks for what is (for all of us burned out AM station engineers) a wonderful nostalgic interlude.
I tested the alternate transmitter by running it on the emergency generator. For redundancy each transmitter (and the building) each had their own power transfer switch. Ron W4BIN
Everything on the second floor for high water is cool, but the ATUs and the generator aren't gonna do you much good when the flood plain fulfills its destiny.
We used to have an lw transmitter here in Ireland for s station called Atlantic 252 ,it used to also make the border fence shake because of its power 500 kw, there's a video here on youtube if you watch it youll a guy put a key in a padlock and it arcs
@@TheBroadcastEngineer Aircraft radar test set we often used the dummy load as a heater, it ran hot enough to cook on, though the normal operation you put a fan on it. Put a new RF absorber into the test cavity the first 5 minutes were going to make a lot of smoke as the volatiles got burnt out of the foam.
The Nautel ransmitters are incredible. I had the previous version which was twice the size of yours. It just sat there and worked silently. Only failure I remember was when one of the big diodes in the AC input shorted. I think the thing cost over $150 by itself. Quite different from the RCA 50KW Water Cooled Doherty I cut my teeth on in 1962. You could put 8 ot 10 of your transmitter inside that old girl. Sure sounded great, though.
✌ Hi. This was a very nice site tour. It has been a while that i have been on your channel. When you had to change out some components on a remote fill xmitr. I am fully retired from this business, but was stunned at how small the NX50 AM xmtr is. Compared to the old 50kw Continental 317C that I used to baby sit back in the day. Same power output, but very small foot print and I bet the station electric bill is cut more than half. lol No noisy blowers, No oil filled transformers, chokes and reactors, and crowbar tubes to change. LMAO Great video
Welcome back! I’ve got a couple more that I need to edit. But yes, those new Nautel and even the GatesAir transmitters are significantly easier on power consumption, heat load in the building, and footprint. And they have much better remote telemetry and control than in the past. At my previous job we still had a 317 at the auxiliary site ready to rock in case it was ever needed.
I always wanted to actually install and use a 50 KW RCA Ampliphase transmitter. Was privileged to tune one up from scratch and test it under 100% modulation at the RCA factory in Meadowlands, Pennsylvania. It used phase modulation to generate an on-air signal that sounded just as good as FM. In an installation like KLAA, driving a multi-tower array, an Ampliphase would probably drive the chief engineer nuts. But gosh… did those things sound great.
Yes a very nice site, and a very dedicated engineer there, who wants to be giving the best most reliable signal as possible, come what may. just wonder what will occur in a big flood when that switch room gets wet.
Indeed! Mike is a great engineer. Paul, his successor, set up a great site. I do find it funny that the transmitter building was required by the Army Corps of Engineering to be on stilts, but not the ATU buildings at the towers.
@@TheBroadcastEngineer Nor the bases of the towers either, though probably the transmitter SWR protection will trip out and stop the operation when water laps past the insulator, and ther same for the ATU shed as well. Not easy for the transmitter though, so high and dry it is. Hopefully Mike has a trailer at home with a boat on it, just in case there is an emergency and he needs to get there, and the land is a little bit past wet.
"Clear Channel" doesn't seem to mean what one would expect. WCCO in Minneapolis is the only station on 830 KHz listed as a clear channel station, but there are 8 other stations broadcasting nighttime on the frequency. KLAA is the most powerful of those, with a nighttime power of 20 KW.
The ATU fence isn't grounded well enough if it's arcing to the door latch on such a hot tower. That could easily burn you while unlocking the gate on a 50,000 watt tower (days).
One afternoon at my last AM before going into TV, we heard gunfire at the transmitter site. Our CE, Maintenance Tech, and I started searching. Our CE found a teenager with a .22 and a scope taking pot shots at our tower lights. We (and a nearby competitor 60 kHz up the dial) had been having problems with lights being shot out until then. The kid's parents knew "somebody" and he didn't even get a slap on the wrist. The other problem with the site (63 acres) was teenagers "parking". Particularly on Friday & Saturday nights. One Friday night episode was hilarious! The 'Mitter Sitter, our Maintenance Tech and I watched two sets of headlights crest the hill by the site and go in different directions. Gary and I coordinated on the output of our two-meter repeater that was on Tower #2. (Ever see an isocoupler for 147 MHz?) Gary was rock-bound with his GE Progline and I was QRP on the repeater output, So, what Gary said went across parts of four states while I was probably not going more than a mile. But, Fitz at the transmitter could hear everything. It was quite hilarious! I chased one car while Gary went after the other. Finally, after it was all over with, the CE got on the repeater and asked what was going on. We told him that we "couldn't talk about it on the air" and we'd tell him on Monday. When we did, he laughed his ass off! My first AM had similar problems. But, being a daytimer there usually nobody there at night. My second AM was co-located with a "secure" AT&T Long Lines site. So, there was never a problem.
@@TheBroadcastEngineer I left out the good stuff about "the parkers". This is a family-friendly channel, isn't it? Also, first time I had to mow the tower site, I found a mattress on the grounds. And, "evidence" of its use! Sad part is, of the AM's I worked at, my last one is now townhouses (the competitor is now single-family) and both diplex into the same array. The competitor no longer has a night signal into its city of license.
How do radio stations know how many ppl are listening to them ...I hear it talked about..but it's over the air it's not like you can count how meny cables are connected like old TV channels...I've always wondered this
Nielsen (the TV measurement company) purchased Arbitron. So they have a system that hides data tones in the audio and they will have volunteers, called Diary Keepers, (not associated with the company or station) wear a pager like device that listens for those tones and records the time stamp. Those pagers devices upload their data to the server and everything gets compiled.
Nice tour. I have been in radio sense I was nine (ham radio and all). I would say a dream job would be to work at a powerhouse station like one of these, but in truth it would be more like the VLA of some other large radio telescope. Peace
Interesting how he talks about the Harris DX-50 Transmitter while the Nautel is providing flawless performance and saving a pile of money on electric bills. The Nautel is FET output and sounds glorious as well. And the Nautel takes up far less space. 🙂
Yes, but many broadcasters still have those DX-50s around. And as I see many times, the older engineer crowd still fawn over the old tube transmitters forgetting about how much work they were to upkeep... :)
@@TheBroadcastEngineer 🤣Not many people would have got the jest of the above. LMAO i LOVED that segment as Data put the chips back in light speed order. And not to confuse a isocouplers with isolinear chips. There not interchangeable 😂.
The little arcs that happen from the oxidation. It’s pretty cool. It’s even cooler when it’s talk programming and you can make out what they’re saying.
Those would be gross environmental conditions. Such as flooding or over saturated ground. That Potomac antenna monitor (beige box with red numerical display) has analog outputs on the back that can be interfaced to a remote control. At my previous job, when they had a directional AM station in Bakersfield, I did that exact thing. Usually, you won’t be making pattern changes unless the antenna monitor shows that it’s really out of whack for a while.
The FCC used to require periodic “proofs of performance” for directional stations. For the night-time and then day-time antenna patterns the received field strength of the on-air signal would be measured at specific locations (referred to as “monitor points”). If the signal strength at each monitor point did not exceed what was predicted in the antenna pattern design, the station (and the FCC) was assured the multi-tower array was in correct adjustment. The monitor point readings were almost always made at night. Monitor points were purposefully located where there was only a small chance that future development would render them inaccessible. They were usually in graveyards… I spent many late nights sitting with a field strength meter in one hand and a two-way radio in the other, giving the director of engineering back at the transmitter site new readings each time he adjusted the antenna tower phasing-all while comfortably supporting my back by leaning on a grave stone.
@@georgeetherege8347 When WEAM-1390 was at its original site, one of the monitoring points was by what would become the main gate of CIA HQ in Langley, VA. That one was always fun...
Correct. MDCL suppresses the carrier when there is programming, and when there is silence, it allows the carrier to come up to full power. Saves a lot in electricity bills.
At full, or nearly full, modulation levels, the transmitter acts like any conventional AM transmitter. During pauses, when the modulation level is (very briefly) essentially zero, the only purpose served by a full power carrier is to keep the automatic volume control (AVC) in the listener’s receiver from bringing up the background noise level. But the”time constant” of a typical AVC will cause a delayed change in level close to the duration of the pause. In that short time, the transmitter can “duck” the carrier power to almost zero with no perceptible change as far as the listener is concerned. Pauses in musical and speech programming are surprisingly frequent so “turning off” the 50 KW carrier in each one results in measurable savings when AC power costs $0.15 to $0.35 per kilowatt-hour.
The two AM stations that iHear runs in my area (620 and 1190 kHz) are using some form of controlled-carrier modulation. I discovered this when I attempted to measure the carrier levels from them using an RF selective level meter, which has a bandwidth setting of 25 Hz (so no sidebands get through). The signal strength needle bobs up and down on these two stations, while others have constant carrier levels. I will have to double-check on the behavior of the carrier on these two stations. I had mistakenly assumed that the carrier level is reduced during pauses in audio, and I wondered, why doesn't the interference level come up when there is silence?
@telepolo Not necessarily. There are plenty of stations with night power levels that high. Night time is directional, so the nighttime pattern may provide sufficient protection for a co-channel station that the power can still be pretty high.
@MrVinamp At 830 kHz it’s not an issue. The dangers you have with RF is heating. The wavelength of 830 kHz is so large that the body is invisible to it. Start getting up to the 900 MHz and higher you then have body parts like eyeballs that are resonant and start to heat up like in the microwave. In fact that is how a microwave works. The FCC’s RF exposure chart is a good view of how frequency is more important than raw power. And keep in mind that this is non-ionizing radiation. X-Rays and the such are a different type of radiation.
I occasionally enjoy your content, but I do not enjoy you being featured so prominently in the video. I'm choosing to unfollow channels that seem to feature the author as the subject matter in favor of channels that focus more on the content I'm interested in. I have no desire to learn anything more about you personally.
Um, ok. Seeing that I’ve been in this video for a very short amount of time and really didn’t talk about anything personal… but you do you. Thanks for watching what you have watched.
@christopherjohn1467 It’s ok. 2 seconds of searching him online shows that’s the type of comments he posts on everyone’s videos. Nothing more than your run of the mill UFO and dog loving troll. But it is worth a chuckle.
The fellow is a great example of a broadcast engineer... has difficulty explaining things, but clearly knows exactly what is going on.
Ones that can explain it well are very rare. You have no idea the prep and writing that goes into any of my videos. So, Mike explaining on the fly is pretty good.
I always wanted to get into broadcasting but never had an avenue in so I went into the public safety radio side. A lot of the job is similar to keeping a station on the air, just the RF power levels, etc. are not the same. I love antenna systems and especially AM DAs. I even met and chatted with Jack Layton on the ham bands, one of the authorities on directional antennas.
The DX-50 is an amazingly reliable transmitter. I once had to 'shotgun' all the blue capacitors Mike was showing us that filter the power modules when I noticed some of them bloating. Another mod we had to do on the DX-50 was very simple: we swapped the red & green LEDs for the local/remote switch. Normally the transmitter is in "remote" mode, but the LED was red as the Harris default. Once we didn't catch that it was in "local" with a green LED and went back to Hollywood. Naturally, there was a power failure that afternoon, and we couldn't turn the transmitter back on remotely, so had to spend 2 hours driving back to the site just to turn the transmitter back on. So we reversed the LEDs, and before leaving, we installed a big red light at the front door that would go on if we left the building with either transmitter in "local" mode. That saved us a lot of trouble over the years because a single red LED really stands out on a panel of all normally green ones.
50kw from such a small transmitter. I remember the hughe 50kw broadcast AM transmitters with huge final tubes. My Dad used to be a radio engineer at WABC and then WHN in NYC.
Nice to see a Belar modulation monitor continuing to serve. I first encountered one in 1969, at KQV (1410, 5 Kw DA-2 five towers) in Pittsburgh, Pennsylvania. Classy transmitter site-nothing like all that silver-plated coils and copper tubing to drive corporate accounting crazy. “Wait, you need HOW MUCH silver out there? Can’t you just use aluminum wire?” With the building elevated like that in the near field of the antennas, there’s nothing resembling “ground” inside. Thanks for what is (for all of us burned out AM station engineers) a wonderful nostalgic interlude.
The grounding is strap on the floor. I saw it, but didn't record it.
So interesting ~! SO modulation lowers the dead-key from 50K to 32K ish... and makes total sense - thus saving a lot of energy while "modulating"
I would think the listener would hear higher noise when listening?
@Kinann the speed at which it happens makes it very difficult to hear.
@@TheBroadcastEngineer Thanks.
I tested the alternate transmitter by running it on the emergency generator. For redundancy each transmitter (and the building) each had their own power transfer switch. Ron W4BIN
You should secure the tower with a fence, otherwise it's at risk of being stolen!
This site has a lot of security. Tower theft isn’t going to be an issue.
Everything on the second floor for high water is cool, but the ATUs and the generator aren't gonna do you much good when the flood plain fulfills its destiny.
We used to have an lw transmitter here in Ireland for s station called Atlantic 252 ,it used to also make the border fence shake because of its power 500 kw, there's a video here on youtube if you watch it youll a guy put a key in a padlock and it arcs
Yikes!! It drew an arc?!
@@TheBroadcastEngineer Aircraft radar test set we often used the dummy load as a heater, it ran hot enough to cook on, though the normal operation you put a fan on it. Put a new RF absorber into the test cavity the first 5 minutes were going to make a lot of smoke as the volatiles got burnt out of the foam.
@@TheBroadcastEngineer if you search Atlantic 252 transmitter site it should be here somewhere
Atlantic 252 used to occasionally make it across the pond into Virginia...
@@johnpinckney4979 wow!!!!
so wheres the power module for the paris 50?
The Nautel ransmitters are incredible. I had the previous version which was twice the size of yours. It just sat there and worked silently. Only failure I remember was when one of the big diodes in the AC input shorted. I think the thing cost over $150 by itself. Quite different from the RCA 50KW Water Cooled Doherty I cut my teeth on in 1962. You could put 8 ot 10 of your transmitter inside that old girl. Sure sounded great, though.
✌ Hi. This was a very nice site tour. It has been a while that i have been on your channel. When you had to change out some components on a remote fill xmitr. I am fully retired from this business, but was stunned at how small the NX50 AM xmtr is. Compared to the old 50kw Continental 317C that I used to baby sit back in the day. Same power output, but very small foot print and I bet the station electric bill is cut more than half. lol No noisy blowers, No oil filled transformers, chokes and reactors, and crowbar tubes to change. LMAO Great video
The Continental 317C was my favorite 50KW rig. Much better than the RCA Amplifuzz or the Gates/Harris MW-50...
Welcome back! I’ve got a couple more that I need to edit.
But yes, those new Nautel and even the GatesAir transmitters are significantly easier on power consumption, heat load in the building, and footprint. And they have much better remote telemetry and control than in the past.
At my previous job we still had a 317 at the auxiliary site ready to rock in case it was ever needed.
DX50, still a fabulous transmitter!
Indeed it is, Professor. Until the parts become unavailable. Then it's a ticking time bomb.
I always wanted to actually install and use a 50 KW RCA Ampliphase transmitter. Was privileged to tune one up from scratch and test it under 100% modulation at the RCA factory in Meadowlands, Pennsylvania. It used phase modulation to generate an on-air signal that sounded just as good as FM. In an installation like KLAA, driving a multi-tower array, an Ampliphase would probably drive the chief engineer nuts. But gosh… did those things sound great.
@@georgeetherege8347 Until they drifted out of tune. And, sometimes they did!
Interessante, o mau contato elétrico do portão fez com que funcionasse como um diodo retificando a RF.
Flood plain , building on stilts , back up generator on the ground ( 1148 )
Genny should be on stilts too
Originally the generator was in the building on stilts... but that also shows you how often it floods.
Hey it worked for Fukishima....oh wait.
Hey there, your videos are really informative, regularly watching all your videos. am an engineer and we have NX200 for AM Transmission🙂
Thank you! Wow an NX200?! Where are you?
Nothing against chief engineers at all. I've known a number of them. They live in a world of their own
They are a mixed breed.
Yes a very nice site, and a very dedicated engineer there, who wants to be giving the best most reliable signal as possible, come what may. just wonder what will occur in a big flood when that switch room gets wet.
Indeed! Mike is a great engineer. Paul, his successor, set up a great site.
I do find it funny that the transmitter building was required by the Army Corps of Engineering to be on stilts, but not the ATU buildings at the towers.
@@TheBroadcastEngineer Nor the bases of the towers either, though probably the transmitter SWR protection will trip out and stop the operation when water laps past the insulator, and ther same for the ATU shed as well. Not easy for the transmitter though, so high and dry it is. Hopefully Mike has a trailer at home with a boat on it, just in case there is an emergency and he needs to get there, and the land is a little bit past wet.
If my cell tower poles are just going straight up how do I install the guys without the tower falling over
I don't understand the question.
"Clear Channel" doesn't seem to mean what one would expect. WCCO in Minneapolis is the only station on 830 KHz listed as a clear channel station, but there are 8 other stations broadcasting nighttime on the frequency. KLAA is the most powerful of those, with a nighttime power of 20 KW.
At 2:00 he states "if (you're) silence, it ramps up to 50Kw..." that is negative modulation. Wow, I didn't know modern AM transmitters did that.
KLAA 830 kHz. Owned by the Los Angeles Angels baseball club.
Whatch out for those Phone Cops. They play hardball.
Also... did that man not learn? NEVER wear a red shirt!
You see elevated enclosures like that all over the place for cell sites here in Thailand.
The ATU fence isn't grounded well enough if it's arcing to the door latch on such a hot tower. That could easily burn you while unlocking the gate on a 50,000 watt tower (days).
Yes, that's a fun find that day. Mike is taking care of it, if he hasn't already. :)
Thank you Brother. That was really interesting.
That's a awesome building
One afternoon at my last AM before going into TV, we heard gunfire at the transmitter site. Our CE, Maintenance Tech, and I started searching. Our CE found a teenager with a .22 and a scope taking pot shots at our tower lights. We (and a nearby competitor 60 kHz up the dial) had been having problems with lights being shot out until then. The kid's parents knew "somebody" and he didn't even get a slap on the wrist. The other problem with the site (63 acres) was teenagers "parking". Particularly on Friday & Saturday nights. One Friday night episode was hilarious! The 'Mitter Sitter, our Maintenance Tech and I watched two sets of headlights crest the hill by the site and go in different directions. Gary and I coordinated on the output of our two-meter repeater that was on Tower #2. (Ever see an isocoupler for 147 MHz?) Gary was rock-bound with his GE Progline and I was QRP on the repeater output, So, what Gary said went across parts of four states while I was probably not going more than a mile. But, Fitz at the transmitter could hear everything. It was quite hilarious! I chased one car while Gary went after the other. Finally, after it was all over with, the CE got on the repeater and asked what was going on. We told him that we "couldn't talk about it on the air" and we'd tell him on Monday. When we did, he laughed his ass off! My first AM had similar problems. But, being a daytimer there usually nobody there at night. My second AM was co-located with a "secure" AT&T Long Lines site. So, there was never a problem.
Those are great stories!!!
@@TheBroadcastEngineer I left out the good stuff about "the parkers". This is a family-friendly channel, isn't it?
Also, first time I had to mow the tower site, I found a mattress on the grounds. And, "evidence" of its use!
Sad part is, of the AM's I worked at, my last one is now townhouses (the competitor is now single-family) and both diplex into the same array. The competitor no longer has a night signal into its city of license.
How do radio stations know how many ppl are listening to them ...I hear it talked about..but it's over the air it's not like you can count how meny cables are connected like old TV channels...I've always wondered this
Nielsen (the TV measurement company) purchased Arbitron. So they have a system that hides data tones in the audio and they will have volunteers, called Diary Keepers, (not associated with the company or station) wear a pager like device that listens for those tones and records the time stamp. Those pagers devices upload their data to the server and everything gets compiled.
@@TheBroadcastEngineer thank you ...would make a cool video i cant be the only one thats woundered this stuff and no one els has done one on it yet
So let me guess, KLAA is a sports station (I confirmed that), and I’m guessing it either once aired or is airing Angels games?
It currently is the home radio station for the Los Angeles Angels of Anaheim.
It's owned by the "Los Angeles Angels of Anaheim", Arte Moreno.
I got a chance to tour WCCO 830 AM back in the 70s. It was about then I figured out to get that job, I'd have to wait until someone died.
The bigger more iconic stations yeah…
@@TheBroadcastEngineer Might be even tougher now, went into semiconductors instead.
Nice tour. I have been in radio sense I was nine (ham radio and all). I would say a dream job would be to work at a powerhouse station like one of these, but in truth it would be more like the VLA of some other large radio telescope.
Peace
The VLA is pretty cool. I want to get a tour of that place one of these days.
@@TheBroadcastEngineer Would love that as well!
Interesting how he talks about the Harris DX-50 Transmitter while the Nautel is providing flawless performance and saving a pile of money on electric bills. The Nautel is FET output and sounds glorious as well. And the Nautel takes up far less space. 🙂
Yes, but many broadcasters still have those DX-50s around. And as I see many times, the older engineer crowd still fawn over the old tube transmitters forgetting about how much work they were to upkeep... :)
@@TheBroadcastEngineer True 🙂
Mod monitor looks a little wimpy...70% modulation???
It's not a quiet signal, that's for sure. Might just have been the programming at the moment when the camera was on it.
Really fascinating. I wonder if the technician is also a ham radio operator?
I believe he is!
5:34.... like isolinear chips!!! hahahaha
HAHAHAHA! Don't let Mr. Shimoda near it unless Data is around. He's the only one who can put them back in time to avert disaster.
@@TheBroadcastEngineer That made laugh loud enough to disturb the dog. Way to go man. Good times
@@TheBroadcastEngineer He was sooo happy too in his pile of chips
@@TheBroadcastEngineer 🤣Not many people would have got the jest of the above. LMAO i LOVED that segment as Data put the chips back in light speed order. And not to confuse a isocouplers with isolinear chips. There not interchangeable 😂.
The fence is modulatin' the RF? That's wild!
The little arcs that happen from the oxidation. It’s pretty cool. It’s even cooler when it’s talk programming and you can make out what they’re saying.
4:45 he states that environmental conditions can change the pattern. How do they know what the pattern is at any given moment?
Those would be gross environmental conditions. Such as flooding or over saturated ground. That Potomac antenna monitor (beige box with red numerical display) has analog outputs on the back that can be interfaced to a remote control. At my previous job, when they had a directional AM station in Bakersfield, I did that exact thing. Usually, you won’t be making pattern changes unless the antenna monitor shows that it’s really out of whack for a while.
The FCC used to require periodic “proofs of performance” for directional stations. For the night-time and then day-time antenna patterns the received field strength of the on-air signal would be measured at specific locations (referred to as “monitor points”). If the signal strength at each monitor point did not exceed what was predicted in the antenna pattern design, the station (and the FCC) was assured the multi-tower array was in correct adjustment. The monitor point readings were almost always made at night. Monitor points were purposefully located where there was only a small chance that future development would render them inaccessible. They were usually in graveyards… I spent many late nights sitting with a field strength meter in one hand and a two-way radio in the other, giving the director of engineering back at the transmitter site new readings each time he adjusted the antenna tower phasing-all while comfortably supporting my back by leaning on a grave stone.
@@georgeetherege8347 When WEAM-1390 was at its original site, one of the monitoring points was by what would become the main gate of CIA HQ in Langley, VA. That one was always fun...
Beautiful facility!
Why isn't the tuning shed elevated also?
Because government regulations don’t make sense. 👍
And the backup generator
2:05. So with no audio sideband power, the power meter reads higher?
Correct. MDCL suppresses the carrier when there is programming, and when there is silence, it allows the carrier to come up to full power. Saves a lot in electricity bills.
@@TheBroadcastEngineer Interesting. So what is the peak envelope power at full modulation?
At full, or nearly full, modulation levels, the transmitter acts like any conventional AM transmitter. During pauses, when the modulation level is (very briefly) essentially zero, the only purpose served by a full power carrier is to keep the automatic volume control (AVC) in the listener’s receiver from bringing up the background noise level. But the”time constant” of a typical AVC will cause a delayed change in level close to the duration of the pause. In that short time, the transmitter can “duck” the carrier power to almost zero with no perceptible change as far as the listener is concerned. Pauses in musical and speech programming are surprisingly frequent so “turning off” the 50 KW carrier in each one results in measurable savings when AC power costs $0.15 to $0.35 per kilowatt-hour.
@@TheBroadcastEngineer Thank you. I learned something today... and that's always a good thing.
The two AM stations that iHear runs in my area (620 and 1190 kHz) are using some form of controlled-carrier modulation. I discovered this when I attempted to measure the carrier levels from them using an RF selective level meter, which has a bandwidth setting of 25 Hz (so no sidebands get through). The signal strength needle bobs up and down on these two stations, while others have constant carrier levels.
I will have to double-check on the behavior of the carrier on these two stations. I had mistakenly assumed that the carrier level is reduced during pauses in audio, and I wondered, why doesn't the interference level come up when there is silence?
What is the output power level after sunset ????
According to their license on the FCC’s website, it says 20kW night.
@@TheBroadcastEngineer Oh that’s pretty high because normally it should be 5K or below
@telepolo Not necessarily. There are plenty of stations with night power levels that high. Night time is directional, so the nighttime pattern may provide sufficient protection for a co-channel station that the power can still be pretty high.
@@TheBroadcastEngineer Ok thanks for your clarification 👍🏼
This is not a healthy job!
In what way is this an unhealthy job?
@@TheBroadcastEngineer That high amount of radiation
@MrVinamp You mean non-ionizing radiation? Light is more dangerous than any radiation you’re getting from a radio tower. You still use lights.
@@TheBroadcastEngineer But 50 KW of rf radiation isn't exactly the same as a light bulb 😏
@MrVinamp At 830 kHz it’s not an issue. The dangers you have with RF is heating. The wavelength of 830 kHz is so large that the body is invisible to it. Start getting up to the 900 MHz and higher you then have body parts like eyeballs that are resonant and start to heat up like in the microwave. In fact that is how a microwave works. The FCC’s RF exposure chart is a good view of how frequency is more important than raw power. And keep in mind that this is non-ionizing radiation. X-Rays and the such are a different type of radiation.
I occasionally enjoy your content, but I do not enjoy you being featured so prominently in the video. I'm choosing to unfollow channels that seem to feature the author as the subject matter in favor of channels that focus more on the content I'm interested in. I have no desire to learn anything more about you personally.
Um, ok. Seeing that I’ve been in this video for a very short amount of time and really didn’t talk about anything personal… but you do you. Thanks for watching what you have watched.
Umm did you watch this video? He was hardly in it.
@christopherjohn1467 It’s ok. 2 seconds of searching him online shows that’s the type of comments he posts on everyone’s videos. Nothing more than your run of the mill UFO and dog loving troll.
But it is worth a chuckle.
@@TheBroadcastEngineer Just another malignant narcissist jealous it's not him.
14:00 is when I started to get a headache lol