Lafayette, LA / Beaumont, TX / Lake Charles, LA - HDTV - Page 151 - AVS Forum
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post #4501 of 9966 Old 04-13-2009, 09:40 AM
 
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Originally Posted by Ace Deprave View Post

Yes, that's it, WLBT, out of Jackson, MS. Supposedly, they would have gotten KPLC, but when Lafayette got their locals, KPLC's tower had been blown down.

Correction, KPLC's tower was NOT blown down..it was KNOCKED down due to the new tower being built next to it FAILING......THAT was due to someone not locking down the gin pole and its track....and high winds DID blow the gin pole loose...but it didnt cause the tower to directly fall..the gin pole slicing through the guy wires did it..and away they went....
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post #4502 of 9966 Old 04-13-2009, 10:04 AM
 
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Originally Posted by Dr Touchtone View Post

Correction, KPLC's tower was NOT blown down..it was KNOCKED down due to the new tower being built next to it FAILING......THAT was due to someone not locking down the gin pole and its track....and high winds DID blow the gin pole loose...but it didnt cause the tower to directly fall..the gin pole slicing through the guy wires did it..and away they went....

Oops.
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post #4503 of 9966 Old 04-13-2009, 10:08 AM
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Originally Posted by hearrean View Post

Ok, well, I'm still not getting it & should be; as I said it doesn't even show in the EPG. Just the SD version is all that's there.

Ken

I've seen several people posting they got this corrected by the online chat or calling them.
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post #4504 of 9966 Old 04-13-2009, 10:09 AM
 
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So now the question becomes why, if the BPT and LC and LFT DMAs are different, how can a satellite carrier bring in a NBC affiliate from Mississippi or even Lake Chares for Lafayette, but cannot bring in an ABC or CBS affiliate from BPT or LFT DMA for Lake Charles?
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post #4505 of 9966 Old 04-13-2009, 10:15 AM
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Originally Posted by cat lady View Post

After the end of analog broadcasting on June, 12, KLFY-DT will indeed flash cut to channel 10 with an effective radiated power (ERP) of 20.3 KW from a height of 529 meters above ground (AG) or 1735' 6".

Whereas KLFY-DT on channel 56 is broadcasting 1000KW from 508 meters (AG) or 1,666' 8".

Is 20.3KW somehow more powerful than 1000KW?
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post #4506 of 9966 Old 04-13-2009, 11:00 AM
 
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Originally Posted by toms111la View Post

Is 20.3KW somehow more powerful than 1000KW?

VHF and UHF are apples and oranges.

20.3 KW from that height is near, though not at, the max for a VHF-hi band transmitter. VHF is not near as fickle as UHF, so with the full power (near max) channel 10 DTV transmitter, the signal should be way more dependable than the full power (maxed) channel 56 transmitter.

By comparison, our local ABC affiliate (DTV channel 50) will revert to channel 12 post transition where they, also a VHF-hi band channel will have an ERP of 160 KW, but only broadcasting from 299 meters AG or 981' +/_. The higher stick of KLFY will play to your advantage, giving more coverage to a broader area.

Just make sure you have a good VHF antenna at your disposal, and the long nightmare should end at that time.

I wish all of y'all good luck.
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post #4507 of 9966 Old 04-13-2009, 11:17 AM
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Originally Posted by cat lady View Post

So now the question becomes why, if the BPT and LC and LFT DMAs are different, how can a satellite carrier bring in a NBC affiliate from Mississippi or even Lake Chares for Lafayette, but cannot bring in an ABC or CBS affiliate from BPT or LFT DMA for Lake Charles?

That is a very good question.
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post #4508 of 9966 Old 04-13-2009, 11:18 AM
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Originally Posted by cat lady View Post

So now the question becomes why, if the BPT and LC and LFT DMAs are different, how can a satellite carrier bring in a NBC affiliate from Mississippi or even Lake Chares for Lafayette, but cannot bring in an ABC or CBS affiliate from BPT or LFT DMA for Lake Charles?

This is something i don't understand either.. There are many markets out there in different parts of the country that share stations from different cities as far as 30 mile apart or more and are considered one market, so i get that..
Since Bmt, L.C. and LFT are all SMALL markets and have in the recent past all shared at least 1 station from the other market, you'd think could all be added to Directv at same time or at least those in lafayette would get KPLC, because that was in fact their designated NBC affiliate as was FOX 29 for beaumont until recently..

One of these days we'll be able to watch locals from wherever we want as long as we pay.. My proposal is that when technology/space allows that Directv allow you to buy 1 additional local network for everyone who have in your area, provided you do have all the local channels already.. I'd love to watch local news and the such from other places i've lived sometimes..
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post #4509 of 9966 Old 04-13-2009, 11:27 AM
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Originally Posted by GlenninCarlyss View Post

Thank you for the DMA info. I have a new Winegard 7084P antenna but I also have a LARGE live oak and a 69KV transmission line just to the west. Right now I am pointed east to get KPLC 7.1, Lafayette ABC 3.1, and LPB 18. I can get Fox 29.1 off the side. I can't seem to get Lafayette 10 CBS (56.1) at all so I was hoping to get the Beaumont stations off of my Direct TV. Maybe when Lafayette gets their locals on the satellite I can pick those up or maybe Lafayette 10 will boost their power in June. Any word about their financial problems effecting their power increase plans?

I live NE of lake charles about 10 miles outside city.. I'm still having trouble getting KLFY consistently on my hr20-700 receiver.. Everything else in lafayette is ok, but 15.1.. I have 29.1 coming in good so need to worry about 15.1...

Last night i reset my antenna zip to reflect L.C. as Primary and Alex as Secondary to see how that would come in and i was able to get a great pic for 5.1 (NBC) and 5.2 (CBS) as well as a couple of other channels 46.1?..

The only problem is when i do this, it eliminate's the Lafayette channels from my guide, so if i can see if a Zip in between L.C. and Alex pulls all in, i will use that.. Then put Laf back to secondary market or use a Zip in Jennings to as primary and Alex as secondary. Not sure if 29.1 will still work under this scenerio though..
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post #4510 of 9966 Old 04-13-2009, 12:26 PM
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Quote:
Originally Posted by cat lady View Post

VHF and UHF are apples and oranges.

20.3 KW from that height is near, though not at, the max for a VHF-hi band transmitter. VHF is not near as fickle as UHF, so with the full power (near max) channel 10 DTV transmitter, the signal should be way more dependable than the full power (maxed) channel 56 transmitter.

By comparison, our local ABC affiliate (DTV channel 50) will revert to channel 12 post transition where they, also a VHF-hi band channel will have an ERP of 160 KW, but only broadcasting from 299 meters AG or 981' +/_. The higher stick of KLFY will play to your advantage, giving more coverage to a broader area.

Just make sure you have a good VHF antenna at your disposal, and the long nightmare should end at that time.

I wish all of y'all good luck.

How long ago did KLFY move from 10 to 56? Has it always been this way for their digital signal? I'm asking because I have a CM 4228 as an antenna, which is a UHF antenna. I've had it in place since July 2007, and have always been able to pick up KLFY. With my D* receiver, I have no idea if it's always been on 56.1, though. I'm hoping I can still catch it after it moves to 10.1.
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post #4511 of 9966 Old 04-13-2009, 12:39 PM
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Originally Posted by Dr Touchtone View Post

Richard, the 1MW is ERP...iirc TPO will be about 110-140KW.....likely still have an IOT in the cabinets but isnt there solid state transmitters now for that (or is it just VHF Im think of?? and no SS UHFs yet at that level?)....BUt either way, its just an amplifier cabinet and the current exciter would drive it....

On most UHF installations of 1000KW ERP the TPO is from 25-45KW depending on antenna gain and transmission line loss. The upper limit on solid state UHF is about 2KW TPO. Anything above that requires an IOT Klystron power amp.
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post #4512 of 9966 Old 04-13-2009, 01:14 PM
 
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Originally Posted by Ace Deprave View Post

How long ago did KLFY move from 10 to 56? Has it always been this way for their digital signal? I'm asking because I have a CM 4228 as an antenna, which is a UHF antenna. I've had it in place since July 2007, and have always been able to pick up KLFY. With my D* receiver, I have no idea if it's always been on 56.1, though. I'm hoping I can still catch it after it moves to 10.1.

Channel 56 was the temporary allotment that was given KLFY for the their digital broadcasts until KLFY-DT can move back to channel 10 post transition. KLFY-DT got their license to cover at 1,000 KW on May 1, 2002. So they have been there since the get-go for digital. Coming up on 7 years now.
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post #4513 of 9966 Old 04-13-2009, 01:19 PM
 
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Originally Posted by FOX44CE View Post

On most UHF installations of 1000KW ERP the TPO is from 25-45KW depending on antenna gain and transmission line loss. The upper limit on solid state UHF is about 2KW TPO. Anything above that requires an IOT Klystron power amp.

Thnak you for the transmitter class. Uh... there's not going to be a test on this is there???

Just kidding. I am glad to have access to that kind of info. I am always in search of tidbits like that, so thank you again.
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post #4514 of 9966 Old 04-13-2009, 01:46 PM
 
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Originally Posted by Retro3 View Post

I live NE of lake charles about 10 miles outside city.. I'm still having trouble getting KLFY consistently on my hr20-700 receiver.. Everything else in lafayette is ok, but 15.1.. I have 29.1 coming in good so need to worry about 15.1...

Last night i reset my antenna zip to reflect L.C. as Primary and Alex as Secondary to see how that would come in and i was able to get a great pic for 5.1 (NBC) and 5.2 (CBS) as well as a couple of other channels 46.1?..

The only problem is when i do this, it eliminate's the Lafayette channels from my guide, so if i can see if a Zip in between L.C. and Alex pulls all in, i will use that.. Then put Laf back to secondary market or use a Zip in Jennings to as primary and Alex as secondary. Not sure if 29.1 will still work under this scenerio though..

I'm not sure what you got on 46.1. there are only 3 stations licensed in Louisiana for channel 46. A class A analog in Baton Rouge and WAFB-DT in Baton Rouge. What's up with that???

And a low power in Lafayette on channel 46.
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post #4515 of 9966 Old 04-13-2009, 02:08 PM
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Originally Posted by cat lady View Post

Channel 56 was the temporary allotment that was given KLFY for the their digital broadcasts until KLFY-DT can move back to channel 10 post transition. KLFY-DT got their license to cover at 1,000 KW on May 1, 2002. So they have been there since the get-go for digital. Coming up on 7 years now.

Thanks!
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post #4516 of 9966 Old 04-13-2009, 03:08 PM
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Originally Posted by cat lady View Post

I'm not sure what you got on 46.1. there are only 3 stations licensed in Louisiana for channel 46. A class A analog in Baton Rouge and WAFB-DT in Baton Rouge. What's up with that???

And a low power in Lafayette on channel 46.

I was going off top of my head as i'm not home now to check the channel, but i know it was something in the high 40's.. I believe i picked up 49.1, natchez mississippi Fox as it comes up under alexandria during channel search.. Is that possible. It was foggy last night, would that help the signals travel distance?

When i get home later, i'll check the channel info to see what i can determine and if it is still got a good signal.
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post #4517 of 9966 Old 04-13-2009, 03:35 PM
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Originally Posted by Retro3 View Post

I live NE of lake charles about 10 miles outside city.. I'm still having trouble getting KLFY consistently on my hr20-700 receiver.. Everything else in lafayette is ok, but 15.1.. I have 29.1 coming in good so need to worry about 15.1...

Last night i reset my antenna zip to reflect L.C. as Primary and Alex as Secondary to see how that would come in and i was able to get a great pic for 5.1 (NBC) and 5.2 (CBS) as well as a couple of other channels 46.1?..

The only problem is when i do this, it eliminate's the Lafayette channels from my guide, so if i can see if a Zip in between L.C. and Alex pulls all in, i will use that.. Then put Laf back to secondary market or use a Zip in Jennings to as primary and Alex as secondary. Not sure if 29.1 will still work under this scenerio though..

And that's the stupid idiotic way of the DirecTV receivers. You can't scan in all the channels you can receive. You are screwed if you live in areas where you can pick up 3 DMA's.
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post #4518 of 9966 Old 04-13-2009, 03:39 PM
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Originally Posted by cat lady View Post

I'm not sure what you got on 46.1. there are only 3 stations licensed in Louisiana for channel 46. A class A analog in Baton Rouge and WAFB-DT in Baton Rouge. What's up with that???

And a low power in Lafayette on channel 46.

WAFB and WBXH are sister stations. I think WBXH is on 39 or something right now and on a digital subchannel of WAFB. It's a MyTV channel.

I've picked up WAFB in Lake Charles with a CM4228 a few times. Not sure how as they are on a short tower of only 46kw on RF 46. Seems like you'd pick up the smoking signal of WGMB's 1000kw rig just down the road from that tower if you can get WAFB. But...RF is always a funny beast when it comes to "shooting skip"

EDIT: And last time I checked the WAFB PSIP was correct and should scan in as 9.x...I think 9.1, 9.2, and 9.4. 9.3 used to be an old TheTube slate.
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post #4519 of 9966 Old 04-13-2009, 04:00 PM
 
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Originally Posted by cat lady View Post

So now the question becomes why, if the BPT and LC and LFT DMAs are different, how can a satellite carrier bring in a NBC affiliate from Mississippi or even Lake Chares for Lafayette, but cannot bring in an ABC or CBS affiliate from BPT or LFT DMA for Lake Charles?

Well, they cant bring in Lake Charles....IIRC when Congress (you know that wonderful bunch of politicians who really run the country), or the FCC, came out with the rules, I THINK it states that any "local" affiliate, if not available, can be filled by a second adj DMA or further....it cannot be from the adj DMA to the one in question....SO BTR is out of the question for LFT and so is LCH for LFT.....There are no locals for LCH (yet) but when they do happen, they wont be able to carry BPT OR LFT (which is STUPID because you can pick UP LFT in LCH and viceversa OTA!)...but thats our smart government (and FCC) for ya!
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post #4520 of 9966 Old 04-13-2009, 04:11 PM
 
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Originally Posted by Retro3 View Post

This is something i don't understand either.. There are many markets out there in different parts of the country that share stations from different cities as far as 30 mile apart or more and are considered one market, so i get that..
Since Bmt, L.C. and LFT are all SMALL markets and have in the recent past all shared at least 1 station from the other market, you'd think could all be added to Directv at same time or at least those in lafayette would get KPLC, because that was in fact their designated NBC affiliate as was FOX 29 for beaumont until recently..

One of these days we'll be able to watch locals from wherever we want as long as we pay.. My proposal is that when technology/space allows that Directv allow you to buy 1 additional local network for everyone who have in your area, provided you do have all the local channels already.. I'd love to watch local news and the such from other places i've lived sometimes..

Used to be you COULD watch any distant "Local" you wanted to; a friend of mine south of Huntsville was an early PRIMEStar customer (now Dish) and he had DOZENs of distant OTA affils on the bird....when I 1st got Dish and moved from DFW back to Houston, I still had all the DFW stations...and then most went away.....except for FOX4...then it went when they put it on the N TX Spot Beam...with SpotBeams being used more and more, you will see LESS offerings of distant locals...of course CATV went the same way....When it first came up in Beaumont in the 70s, 8, 11, 13 and I THINK 26 out of Houston were all on the Cable....then eventually all went away except 8 (I grew up watching MARVIN ZINDLER EYEWITNESS NEWS and his famous roach reports on Fridays....along with Dave Ward and the rest of the crew on 13...and MOST are still there....why screw with success????)

BTW 64 WAS the official Beaumont FOX affiliate until Jan 1, 2009...29? legally it serves the Lake Charles market, NOT Beaumont...
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post #4521 of 9966 Old 04-13-2009, 04:20 PM
 
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Originally Posted by toms111la View Post

Is 20.3KW somehow more powerful than 1000KW?

Given RF56 vs RF 10, almost!!! Also you need to factor in signal loss, obstructions, foilage atternuation, etc....plus the 56 antenna is sidemounted...10 is topmounted...

Look at the coverage (service contour) maps at:
http://www.fcc.gov/fcc-bin/tvq?list=0&facid=35059

Look at KLFY TV on 10 (analog) vs KLFY DT 56 and KLFY DT 10.
Latest is under the modification of their Construction Permit...
(the 56 is not 100% accurate since they are sidemounted and that is causing pattern distortion) These maps are probably a little over the limit so dont count the circle as definite......its 50/50 by the time you get to the circle.
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post #4522 of 9966 Old 04-13-2009, 04:23 PM
 
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Originally Posted by FOX44CE View Post

On most UHF installations of 1000KW ERP the TPO is from 25-45KW depending on antenna gain and transmission line loss. The upper limit on solid state UHF is about 2KW TPO. Anything above that requires an IOT Klystron power amp.

DAMN there I go thinking of 5 MW ERP analogs again! I stand corrected.....
thanks!
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post #4523 of 9966 Old 04-13-2009, 04:28 PM
 
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Originally Posted by digiblur View Post

And that's the stupid idiotic way of the DirecTV receivers. You can't scan in all the channels you can receive. You are screwed if you live in areas where you can pick up 3 DMA's.


And to think I thought the DISH 722 was stupid since it would not read the OTA EPG!!!
but it does allow me to add anything it can scan (or add manually)..
I have all the Houston DTs as well as BPT and LCH and some LFTs in the list...BUT when I go to KVHP, it only says "Digital Service" ARRRGG I have to go down to 26-0 off the bird and see what FOX has on later that night via KRIV in Houston. Was looking at maybe switching to Direct...but now I think I'll stay with DISH (Direct has very low prices and is including locals for free now.....guess DISH has gotten to them after all the tropical storms, etc we have had.
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post #4524 of 9966 Old 04-13-2009, 05:06 PM
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Originally Posted by FOX44CE View Post

In digital UHF transmitters the final power amplifier is a quasi-linear IOT Klystron tube. Radar systems use a small klystron tube as an oscillator but there have been many types of Klystrons developed over the years as power amplifiers.

Magnetrons are high power pulsed oscillators used only in Radar systems.

Four and five cavity high power non-linear Klystron amplifiers (up to 60KW) have been used in UHF analog television transmitters for over 25 years.

Because digital television requires an almost perfectly linear power amplifier, the IOT Klystron was developed to provide both linearity and high efficiency.

Thanks, I stand corrected, as well.

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post #4525 of 9966 Old 04-13-2009, 05:36 PM
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Originally Posted by FOX44CE View Post
On most UHF installations of 1000KW ERP the TPO is from 25-45KW depending on antenna gain and transmission line loss. The upper limit on solid state UHF is about 2KW TPO. Anything above that requires an IOT Klystron power amp.
According to their engineering exhibit, KBTV-DT's Transmiter output will be 42.8 KW. Here's the straight poop.

 

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post #4526 of 9966 Old 04-13-2009, 05:36 PM
 
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Originally Posted by Retro3 View Post

I was going off top of my head as i'm not home now to check the channel, but i know it was something in the high 40's.. I believe i picked up 49.1, natchez mississippi Fox as it comes up under alexandria during channel search.. Is that possible. It was foggy last night, would that help the signals travel distance?

When i get home later, i'll check the channel info to see what i can determine and if it is still got a good signal.


Yeah, 49.1 would be it if that is what WNTZ is mapped to. And yes, fog will sometimes duct RF into your antenna. I believe that it is a FOX affiliate. It is licensed to Natchez, Mississippi.

As a side note, WNTZ was one of, if indeed not the first, "W" station that I ever received when I started DXing back in the early 80's.. WXXV out of Biloxi was another early log that I captured along with the some of the "Ws" out of Baton Rouge and "Nawlins".
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post #4527 of 9966 Old 04-13-2009, 06:13 PM
 
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With KBMT remaining the only VHF Station - Post Transition. Does that give them any coverage advantage? I'm just trying to figure out the logic in staying VHF. Could economics be playing a major role in that decision?
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post #4528 of 9966 Old 04-13-2009, 06:16 PM
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Originally Posted by Dr Touchtone View Post

Richard, the 1MW is ERP...iirc TPO will be about 110-140KW.....likely still have an IOT in the cabinets but isnt there solid state transmitters now for that (or is it just VHF Im think of?? and no SS UHFs yet at that level?)....BUt either way, its just an amplifier cabinet and the current exciter would drive it....

In theory, I could indeed add enough amplifier cabinets to my current solid state transmitter and achieve 1 Megawatt. However, the power bill would be at least 3 times the cost of the same transmitter using an IOT tube.

The efficiency of a UHF tube transmitter is MUCH higher than that of a solid state UHF transmitter. My single transmitter cabinet is capable of 7 KW (average) power. If I had enough room for the 20 cabinets that 140K Xmit power would require, the RF plumbing between them would be a nightmare. For that reason alone, I would go buy an IOT transmitter.

I doubt that any VHF transmitter for use in the USA is designed to be capable of 140Kw although you could just add cabinets to get there, I suppose. The FCC would never license it with that much transmitter power unless the antenna gain was in the negative range.

Both of my Harris digital exciters must be modified for use with an IOT transmitter. I can't just swap the exciter between a Solid State and tube transmitter. The pre-correction circuits (among other things) have to be changed to compensate for the different operating characteristics of Solid State and tube final amplifiers. At least that's what the Harris engineer told me back in 2002 when we installed the transmitter.


Richard
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post #4529 of 9966 Old 04-13-2009, 06:50 PM
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Quote:
Originally Posted by defdog View Post

With KBMT remaining the only VHF Station - Post Transition. Does that give them any coverage advantage? I'm just trying to figure out the logic in staying VHF. Could economics be playing a major role in that decision?

It's supposed to have an coverage advantage, but that is seconday to the power savings when operating a VHF transmitter instead of a UHF transmitter. If it were not for the almost constant electrical interference we experience on channel 6 analog in our area, I would have gone back to channel 6 for digital.

In the analog world, UHF has to put out 1 to 5 megawatts (depending on channel) to equal the coverage area of a low VHF running 100 Kw (such as channel 6). Channel 12 (KBMT) requires about 350 KW to achieve the same coverage area as KFDM in the analog domain. Analog channel 4 (KBTV) with 100Kw should have a slightly larger coverage area than my analog channel 6.

The use of digital or analog modulation does not change basic physics. The higher the frequency, the higher the power needed to achieve the same coverage area.

But you must remember that analog is measured in "peak power" while digital power is measured in "average power". Another set of apples and oranges. 50Kw in digital is more power than 50 Kw in analog.

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post #4530 of 9966 Old 04-13-2009, 06:56 PM
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I found one incorrect setting on my audio processor and changed it. Let me know if all my work was rewarded with 1/10 of an additional audio channel.

I am about "That close" to purchasing the 5.1 SS speaker system for monitoring purposes in master control. Time is all I need now.


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