The Official AVS Antenna and Related Hardware Topic! - Page 580 - AVS Forum | Home Theater Discussions And Reviews
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post #17371 of 17920 Old 08-21-2018, 07:00 AM
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Originally Posted by carillon View Post
Thanks for the reply. How do I physically do this ground? The electric panel is completely on the other side of the house and I assume that's where the grounding rod will be.
If the coax is connected to a piece of equipment that has a 3-wire cord that is connected to a properly wired 3-wire outlet, that should ground the coax shield.

If the coax is connected to AC operated equipment that only has a 2-wire cord, it will not be grounded. If you DO have an interference or overload problem, you can make a simple test by connecting the coax grounding block to the house electrical system ground with a spare 3-wire plug inserted in a properly wired 3-wire outlet. Just ONE wire for grounding in that spare plug, please.





Your FM signals:

http://www.fmfool.com/modeling/tmp/9...4/Radar-FM.png
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If you can not measure it, you can not improve it.
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Last edited by rabbit73; 08-21-2018 at 07:06 AM.
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post #17372 of 17920 Old 08-21-2018, 07:05 AM
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Quote:
Originally Posted by rabbit73 View Post
If the coax is connected to a piece of equipment that has a 3-wire cord that is connected to a properly wired 3-wire outlet, that should ground the coax shield.

If the coax is connected to AC operated equipment that only has a 2-wire cord, it will not be grounded. If you DO have an interference or overload problem, you can make a simple test by connecting the coax grounding block to the house electrical system ground with a spare 3-wire plug inserted in a properly wired 3-wire outlet.







Your FM signals:


http://www.fmfool.com/modeling/tmp/9...4/Radar-FM.png
Good to know. The coax will run to my tech closet and connect to a splitter/amp to feed 5 TVs. Not sure if the splitter/amp is available with a 3-prong plug.
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post #17373 of 17920 Old 08-23-2018, 11:06 AM
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Originally Posted by carillon View Post
Thanks for the reply. I think I'll wait and see how it works once we move in later this year.
There are convenient "TV" outlet surge protectors that also have 2 female passthru F connectors that Protect and ground the antenna coax to the ground lug of the AC socket, such as :

https://smile.amazon.com/gp/product/...?ie=UTF8&psc=1

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post #17374 of 17920 Old 08-26-2018, 10:14 AM
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Any recommendations for an outdoor antenna amplifier?

We want to cut the cord but I am having a hard time getting all the stations I want.

I do have an antenna, a Channel Master rated for I think 90 miles.

Thanks.
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post #17375 of 17920 Old 08-26-2018, 10:34 AM
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Quote:
Originally Posted by bladerunner6 View Post
Any recommendations for an outdoor antenna amplifier?

We want to cut the cord but I am having a hard time getting all the stations I want.

I do have an antenna, a Channel Master rated for I think 90 miles.

Thanks.
Hello, bladerunner6

We would need a lot more information to give you accurate advice about a preamp; at least a location and TVFool report as required in the sticky:
https://www.avsforum.com/forum/25-hd...-1st-post.html

Which stations that you want are hard to get?

What is the model number of the antenna?

Where is the antenna located?

How long is the coax from the antenna to the TV?

You can do a signal report here:
http://www.tvfool.com/index.php?opti...pper&Itemid=29

If you can not measure it, you can not improve it.
Lord Kelvin, 1883
www.megalithia.com/elect/aerialsite/dttpoorman.html

Last edited by rabbit73; 08-26-2018 at 10:38 AM.
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post #17376 of 17920 Old 09-09-2018, 05:17 AM
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Antenna analyzer - utility of SWR/impedance/return loss?

I borrowed an MFJ-226 antenna analyzer from a friend, and aside from using it to check my HF antenna used for transmitting on the amateur radio bands, I got to thinking about its possible utility for checking my TV antenna receiving performance. It will only scan up to 230 Mhz, so would cover to hi-VHF...but I'm just wondering if I take the preamp/dist. amp out of the line, would the analyzer measurements for SWR, impedance, return loss etc. be of any utility for assessing the antenna (using 30-2476 for hi-VHF) and/or feed line performance? Or is there minimal utility of these measurements for TV antenna receiving performance?

Bruce KX4AZ
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post #17377 of 17920 Old 09-09-2018, 07:08 AM
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Sure, you can measure it but I suspect the SWR will not be as good as you'd like to see. And there's nothing you can do about it. As long as the antennas work then it's okay.
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post #17378 of 17920 Old 09-11-2018, 04:43 PM
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Quote:
Originally Posted by rabbit73 View Post
Hello, bladerunner6

We would need a lot more information to give you accurate advice about a preamp; at least a location and TVFool report as required in the sticky:
https://www.avsforum.com/forum/25-hd...-1st-post.html

Which stations that you want are hard to get?

What is the model number of the antenna?

Where is the antenna located?

How long is the coax from the antenna to the TV?

You can do a signal report here:
http://www.tvfool.com/index.php?opti...pper&Itemid=29
Here is my TV Fool report

http://www.tvfool.com/?option=com_wr...9038d5c06a07b5

My difficult to get stations are WOOD-DT and WWMT- NBC and CBS affiliates

The antenna is located on our deck, although I might be able to mount to the side of the house- in on the south side.

The antenna is a Channel Master CM3018.

The length of coax is 50-60 feet.

I was thinking of this amplifier because I do lov Crutchfield.

https://www.crutchfield.com/p_659777...ster-7777.html

Thanks so much!

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post #17379 of 17920 Old 09-11-2018, 06:40 PM
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Quote:
Originally Posted by bladerunner6 View Post
Here is my TV Fool report

http://www.tvfool.com/?option=com_wr...9038d5c06a07b5

My difficult to get stations are WOOD-DT and WWMT- NBC and CBS affiliates

The antenna is located on our deck, although I might be able to mount to the side of the house- in on the south side.

The antenna is a Channel Master CM3018.
Thank you for the report and details. You will probably need a preamp, but a lot depends upon the actual location of the antenna.

Your report assumes that your antenna will be outside, in the clear, with no trees or buildings in the signal path.

If your antenna is in the clear, and you aimed it at 42 degrees, the 7777 would be overloaded, and so would your tuner. CM does have a caution about overload:
https://www.channelmaster.com/TV_Ant..._p/cm-7777.htm

The last 7777 that I ordered had a gain of only 24 dB instead of 30 dB. I suspect that they made a silent design change because they had received returns from customers that had used it in strong signal areas.

The best results for an antenna are when it is aimed directly at the transmitter, but if there are trees or buildings in the signal path from 109 degrees, you might not overload your 7777. If it doesn't work for you, then return it.

If you can not measure it, you can not improve it.
Lord Kelvin, 1883
www.megalithia.com/elect/aerialsite/dttpoorman.html

Last edited by rabbit73; 09-11-2018 at 06:48 PM.
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post #17380 of 17920 Old 09-12-2018, 03:01 AM
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Quote:
Originally Posted by rabbit73 View Post
Thank you for the report and details. You will probably need a preamp, but a lot depends upon the actual location of the antenna.

Your report assumes that your antenna will be outside, in the clear, with no trees or buildings in the signal path.

If your antenna is in the clear, and you aimed it at 42 degrees, the 7777 would be overloaded, and so would your tuner. CM does have a caution about overload:
https://www.channelmaster.com/TV_Ant..._p/cm-7777.htm

The last 7777 that I ordered had a gain of only 24 dB instead of 30 dB. I suspect that they made a silent design change because they had received returns from customers that had used it in strong signal areas.

The best results for an antenna are when it is aimed directly at the transmitter, but if there are trees or buildings in the signal path from 109 degrees, you might not overload your 7777. If it doesn't work for you, then return it.
I should add I do have trees in the way.

Also, I did try a cheap internal pre-amp and that didn’t help but someone suggested I try an external one that is closer to the antenna.

So should I go for the Channelmaster pre-amp or a lower gain model.

Thanks so much, you have been helpful.
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post #17381 of 17920 Old 09-12-2018, 02:10 PM
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Quote:
Originally Posted by tustinfarm View Post
I borrowed an MFJ-226 antenna analyzer from a friend, and aside from using it to check my HF antenna used for transmitting on the amateur radio bands, I got to thinking about its possible utility for checking my TV antenna receiving performance. It will only scan up to 230 Mhz, so would cover to hi-VHF...but I'm just wondering if I take the preamp/dist. amp out of the line, would the analyzer measurements for SWR, impedance, return loss etc. be of any utility for assessing the antenna (using 30-2476 for hi-VHF) and/or feed line performance? Or is there minimal utility of these measurements for TV antenna receiving performance?

Bruce KX4AZ
I analyzed "similar" Stellar Labs Hi-VHF 9-El Yagi (30-2475), which exhibited EXCELLENT SWR:
https://imageevent.com/holl_ands/yag...agistellarlabs

IF you (or anyone else) could provide detailed Measurements and PHOTOS (with Ruler also shown), then I would gladly do the same for the 12-El 30-2476. But since 9-El was Excellent, I would expect 12-El would NOT have any SWR Issues.

===============================================
EXCESSIVE SWR can result in Small-Moderate amounts of Miss-Match Loss at integers of 1/2-Wavelength along the line(I try to keep SWR under 2.7, corresponding to Miss-Match Loss under 1.0 dB)....which would ONLY be an issue for those Channels in which the Null Occurs on the END of the Coax...which would be fairly RARE. However, Dr. Odev Bendov (former Dielectric TX Antenna Engineer), Dr. Yiwan Wu (Head of CRC's DTV Division), et.al. determined that EXCESSIVE SWR caused an ADDITIONAL Loss of Sensitivity in DIGITAL Signals (they miss-labeled it as an Increase in Noise Figure), which is readily measured in his TX (and RX) Antennas using an EVM (Error Vector Magnitude) Digital Waveform Meter [EVM is also related to MER (Modulation Error Ratio) measurement]:
https://www.electronicdesign.com/eng...ctor-magnitude [EVM Explained, 8VSB is Amplitude ONLY]
http://avateq.com/dat/content/image/...SC_v2_main.jpg [EVM meaures 8VSB "EYE" Opening]

https://www.researchgate.net/profile...ce-indices.pdf
https://www.researchgate.net/publica...rmance_indices

Fortunately, EVM degradation is very minimal when using a Mast-Mounted Preamp, since signal reflections up and down the very short Coax do NOT result in significant delay times.

===============================================
In the HF (and other Bands), an ANTENNA TUNER is typically used to improve SWR mis-match to the Antenna...it consists of various L-C Networks in different configurations. If you KNOW the measurements of an Antenna, then a 4nec2 Model can be constructed to display Gain, SWR, etc vs Frequency.....the 4nec2 program also includes a "L/Pi/T Network" Calculator which can be used to calculate Performance for various Networks [I would need to walk someone thru the procedure]. You can also include "Loading" Cards in the 4nec2 File to TRY different Networks...the simplest of which would be a SMALL amount of Capacitance across the Antenna Leads [NOT obvious cuz Card is for ADMITTANCE and NOT Capacitance or Inductance].

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post #17382 of 17920 Old 09-12-2018, 04:08 PM
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Quote:
Originally Posted by bladerunner6 View Post
I should add I do have trees in the way.
Trees block TV signals, especially when they are wet.
Quote:
Also, I did try a cheap internal pre-amp and that didn’t help but someone suggested I try an external one that is closer to the antenna.
What someone told you is true; a preamp is usually (but not always, if you need the attenuation of the coax*) more effective when it is mounted close to the antenna.
Quote:
The antenna is located on our deck, although I might be able to mount to the side of the house- in on the south side.
Which side of the house is the deck on, the rear? Which direction does it face, south? Is it a 2nd floor deck?
Quote:
So should I go for the Channelmaster pre-amp or a lower gain model.
I wish I could give you a precise answer, but I don't have enough information about your location. If I were there, I could make some measurements with my signal level meter and see if the signal paths were clear of obstructions. If you could show us some photos of the antenna location and what the signal path looks like from 109, that might help. Ideally, I would like to look at a satellite view of your location to see the green signal lines, but you would need to give me the coordinates of your antenna on the deck in a PM.

The problem with the 7777 is that if it is even partially overloaded by the strong signals, it becomes more difficult to receive the weaker signals. Channel Master also makes the 7778 which is a medium gain preamp, and they make the 7777HD which has high and low gain settings. I don't like the way the 7777HD mounts because it looks less protected from the weather than the 7777 and the 7778 which have the coax connections on the bottom. I have used the 7777HD with an indoor antenna and it works well. Channel Master has a new 7778HD, but I haven't tested it yet.

You must be prepared to make some more experiments to see what works well for your location.

I don't have your exact location, but an FM Fool report indicates that your local FM transmitters might interfere with the reception of WOOD-DT and WWMT.
http://www.fmfool.com/modeling/tmp/1...8/Radar-FM.png

Some preamps have an FM filter, but it might not have enough attenuation for strong FM signals; an external FM filter can be added between the antenna and the input of the preamp.

*I recall an interesting case on the Canadian forum. The poster was getting good results with his preamp mounted at the lower end of his 50 ft coax. He moved his preamp up near the antenna, and it didn't work as well there. He was upset set because he thought it SHOULD be near the antenna. We told him to put it back down below where it worked better. It turns out that it worked better below because the attenuation of the coax between the antenna and the input of the preamp was just right to optimize his antenna gain and preamp for the signals at his location. To put in technical terms, his preamp SFDR (Spurious-Free Dynamic Range) matched his Signal Dynamic Range plus 15 dB for the minimum required SNR for his Weakest Desired Signal.

If you can not measure it, you can not improve it.
Lord Kelvin, 1883
www.megalithia.com/elect/aerialsite/dttpoorman.html

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post #17383 of 17920 Old 09-12-2018, 05:43 PM
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To bladerunner6 near Holland MI

Quote:
Originally Posted by rabbit73 View Post
Trees block TV signals, especially when they are wet.
What someone told you is true; a preamp is usually (but not always, if you need the attenuation of the coax) more effective when it is mounted close to the antenna.
Which side of the house is the deck on, the rear? Which direction does it face, south? Is it a 2nd floor deck?
I wish I could give you a precise answer, but I don't have enough information about your location. If I were there, I could make some measurements with my signal level meter and see if the signal paths were clear of obstructions. If you could show us some photos of the antenna location and what the signal path looks like from 109, that might help. Ideally, I would like to look at a satellite view of your location to see the green signal lines, but you would need to give me the coordinates of your antenna on the deck in a PM.

The problem with the 7777 is that if it is even partially overloaded by the strong signals, it becomes more difficult to receive the weaker signals. Channel Master also makes the 7778 which is a medium gain preamp, and they make the 7777HD which has high and low gain settings. I don't like the way it mounts because it looks less protected from the weather than the 7777 and the 7778 which have the coax connections on the bottom. I have used the 7777HD with an indoor antenna and it works well. Channel Master has a new 7778HD, but I haven't tested it yet.

You must be prepared to make some more experiments to see what works well for your location.

I don't have your exact location, but an FM Fool report indicates that your local FM transmitters might interfere with the reception of WOOD-DT and WWMT.
http://www.fmfool.com/modeling/tmp/1...8/Radar-FM.png
Hello fellow West Michigander bladerunner6!

rabbit73 provides all of us sage wisdom on this and other sites. Plus he's prompt with his thoughts.

He mentions FM interference--that came to mind for me, too.

Further, since your TVFool brought light that you were in the West Michigan market, I recommend we continue your topic there. I've typed up a rather lengthy (but hopefully insightful) reply:

https://www.avsforum.com/forum/45-lo...l#post56800092

Thanks again for everything rabbit73!

Cheers,
Statmanmi
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post #17384 of 17920 Old 09-15-2018, 03:50 PM
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Could somebody please give me some advice on the type of antenna I should get, whether to get an amp/preamp, and the OTA DVR that would best suit me? This is my first time setting up an outdoor antenna and I'd like to make sure I get all the right equipment.

I live in Florida, so it rains quite a bit down here, and I will be mounting the antenna to my house's fascia. I have 3 TVs and would like to have them hooked into a whole house DVR (I've got a NAS for storing the recordings). The stations I'm targeting are all UHF, are around 20 miles away, and between 108-115° ESE of me. I attached my results from TV Fool.
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post #17385 of 17920 Old 09-15-2018, 05:26 PM
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Quote:
Originally Posted by MagicKnights View Post
Could somebody please give me some advice on the type of antenna I should get, whether to get an amp/preamp, and the OTA DVR that would best suit me? This is my first time setting up an outdoor antenna and I'd like to make sure I get all the right equipment. The stations I'm targeting are all UHF, are around 20 miles away, and between 108-115° ESE of me. I attached my results from TV Fool.
Hello, MagicKnights

Thank you for the report image, but the sticky requires a link to a TVFool report and your location.
https://www.avsforum.com/forum/25-hd...-1st-post.html

I estimate your location to be in Longwood, north of Orlando.

There is no UHF NBC channel at the ESE. There are 3 WESH transmitters.
https://www.rabbitears.info/market.p...&callsign=WESH

The UHF WESH is to the north, but your antenna will be aimed ESE. You will need a UHF/VHF-High combo antenna for NBC on real channel 11. I suggest the Antennas Direct C2VJ. It is being replaced by the C2MAX, which doesn't come with a reflector; I prefer the older C2VJ for your location, but it is hard to find.
https://www.amazon.com/dp/B007RH5GZI..._t1_B01LXGC87U


If there are any trees in the signal path, they will interfere with reception.

If the antenna is outside, the coax shield should be grounded with a grounding block that is connected to the house electrical system ground with 10 gauge copper wire for electrical safety and to reject interference. For further compliance with the electrical code (NEC), the mast should also be grounded in a similar manner to drain any buildup of static charge which will tend to discourage a strike, but the system will not survive a direct strike.



Because of UHF Repack by the FCC, there will be channel changes in your area:
https://www.rabbitears.info/repackch...h=&lss=&status=

Don't be surprised if your question gets moved by the moderator to the local reception thread.


I will leave the DVR advice to others who know more about it than I do.

If you can not measure it, you can not improve it.
Lord Kelvin, 1883
www.megalithia.com/elect/aerialsite/dttpoorman.html

Last edited by rabbit73; 09-15-2018 at 08:40 PM.
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post #17386 of 17920 Old 09-16-2018, 01:05 AM
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Quote:
Originally Posted by MagicKnights View Post
Could somebody please give me some advice on the type of antenna I should get, whether to get an amp/preamp, and the OTA DVR that would best suit me? This is my first time setting up an outdoor antenna and I'd like to make sure I get all the right equipment.

I live in Florida, so it rains quite a bit down here, and I will be mounting the antenna to my house's fascia. I have 3 TVs and would like to have them hooked into a whole house DVR (I've got a NAS for storing the recordings). The stations I'm targeting are all UHF, are around 20 miles away, and between 108-115° ESE of me. I attached my results from TV Fool.
I recently helped a friend with an antenna in Melbourne Fla back in June. All the Orlando UHF stations were very easy to receive with an indoor antenna, except WESH Channel 2 on VHF channel 11 was impossible to decode inside the house. I placed a Marathon Antenna I had ordered on his outside patio and it pulled in the problem WESH signal very strong with a full 10 bars on the Samsung signal meter. So a good VHF antenna outside with an amp may be the best hope for pulling in WESH, as digital VHF can be problematic.

The Marathon Antenna is a good UHF flat panel with an added dipole for VHF. It also has a built in preamp which gives it stronger gain than the nearly identical Antop 400BV which uses an external inline amp instead. If necessary you can add a Channel Master distribution amp down the line to split the signal, but the Marathon amp may be strong enough for a regular splitter. The Marathon antenna worked very well at his location in Melbourne and it is a good, discreet, compact antenna. Sold on Amazon.

But there may be other choices such as Winegard 7694 or Clearstream 2MAX but depends on location and preference. And with those antennas you may need to add an amp.
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post #17387 of 17920 Old 09-16-2018, 06:14 AM
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Quote:
Originally Posted by MagicKnights View Post
Could somebody please give me some advice on the type of antenna I should get, whether to get an amp/preamp,
Use a preamp with caution. Your signals are strong enough to overload a preamp with an outdoor antenna. Try it without first.

If you can not measure it, you can not improve it.
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post #17388 of 17920 Old 09-16-2018, 08:56 AM
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Quote:
Originally Posted by rabbit73 View Post
Trees block TV signals, especially when they are wet.
What someone told you is true; a preamp is usually (but not always, if you need the attenuation of the coax*) more effective when it is mounted close to the antenna.
Which side of the house is the deck on, the rear? Which direction does it face, south? Is it a 2nd floor deck?
I wish I could give you a precise answer, but I don't have enough information about your location. If I were there, I could make some measurements with my signal level meter and see if the signal paths were clear of obstructions. If you could show us some photos of the antenna location and what the signal path looks like from 109, that might help. Ideally, I would like to look at a satellite view of your location to see the green signal lines, but you would need to give me the coordinates of your antenna on the deck in a PM.

The problem with the 7777 is that if it is even partially overloaded by the strong signals, it becomes more difficult to receive the weaker signals. Channel Master also makes the 7778 which is a medium gain preamp, and they make the 7777HD which has high and low gain settings. I don't like the way the 7777HD mounts because it looks less protected from the weather than the 7777 and the 7778 which have the coax connections on the bottom. I have used the 7777HD with an indoor antenna and it works well. Channel Master has a new 7778HD, but I haven't tested it yet.

You must be prepared to make some more experiments to see what works well for your location.

I don't have your exact location, but an FM Fool report indicates that your local FM transmitters might interfere with the reception of WOOD-DT and WWMT.
http://www.fmfool.com/modeling/tmp/1...8/Radar-FM.png

Some preamps have an FM filter, but it might not have enough attenuation for strong FM signals; an external FM filter can be added between the antenna and the input of the preamp.

*I recall an interesting case on the Canadian forum. The poster was getting good results with his preamp mounted at the lower end of his 50 ft coax. He moved his preamp up near the antenna, and it didn't work as well there. He was upset set because he thought it SHOULD be near the antenna. We told him to put it back down below where it worked better. It turns out that it worked better below because the attenuation of the coax between the antenna and the input of the preamp was just right to optimize his antenna gain and preamp for the signals at his location. To put in technical terms, his preamp SFDR (Spurious-Free Dynamic Range) matched his Signal Dynamic Range plus 15 dB for the minimum required SNR for his Weakest Desired Signal.
what does one do when their expensive antenna system gets knocked down by a hurricane?
tjv
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post #17389 of 17920 Old 09-16-2018, 10:16 AM
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Originally Posted by rviele View Post
what does one do when their expensive antenna system gets knocked down by a hurricane?
tjv
Is that a hypothetical question, or did it happen to you in Havre de Grace, MD?

I would get very upset, clean up the mess, start thinking about a temporary antenna so I could get at least something on the TV, and then get an estimate for a replacement system.

If you can not measure it, you can not improve it.
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post #17390 of 17920 Old 09-16-2018, 11:27 AM
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Originally Posted by rviele View Post
what does one do when their expensive antenna system gets knocked down by a hurricane?
tjv
Either file a claim against your homeowner's insurance (if loss exceeds your deductible) or else suck it up and fix it out of pocket. Same for any other covered (or not covered) loss due to a storm. It's all part of recovering from a storm event.
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post #17391 of 17920 Old 09-18-2018, 06:25 AM
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Quote:
Originally Posted by rabbit73 View Post
Is that a hypothetical question, or did it happen to you in Havre de Grace, MD?

I would get very upset, clean up the mess, start thinking about a temporary antenna so I could get at least something on the TV, and then get an estimate for a replacement system.
actually it did happen to me. twice.
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post #17392 of 17920 Old 09-18-2018, 12:04 PM
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What would cause two TVs, one 10 years old and one brand new, to have different levels of success receiving channels with the same external indoor antenna in the same location? My brand new TV can't pick up the channels my ten-year-old TV can, with the same external indoor antenna in the same location. How can I ensure I buy a TV that can receive these channels with my antenna?
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post #17393 of 17920 Old 09-18-2018, 01:35 PM
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The sensitivity of TV tuners can vary a lot. Unfortunately, there are no published tuner sensitivity test results to guide you.

The ATSC has published tuner sensitivity guidelines, but they are not mandatory.

ATSC Recommended Practice:
Receiver Performance Guidelines
Document A/74:2010, 7 April 2010

RECEIVER PERFORMANCE GUIDELINES

Quote:
5.1 Sensitivity
Quote:
A DTV receiver should achieve a bit error rate in the transport stream of no worse than 3x10E-6 (i.e., the FCC Advisory Committee on Advanced Television Service, ACATS, Threshold of Visibility, TOV) for input RF signal levels directly to the tuner from –83 dBm to –5 dBm for both the VHF and UHF bands.
When the digital to analog converter boxes (CECBs) came out 10 years ago, they had to meet government specs to qualify for the coupon program, so they had the best tuners for OTA. Slowly, the TV tuners became just as sensitive.

Now, the pendulum is swinging in the other direction. The TV manufacturers aren't concerned about OTA tuner sensitivity because most users have their TV connected to a cable box with an HDMI cable. Even worse, some "TVs" don't even have a tuner. They are called displays; we used to call them monitors.

The only way to be sure is to test a TV before buying.

The way I test tuner sensitivity is to set up two TVs with a splitter and a variable attenuator. I increase the attenuation to make the signal weaker to the point of signal dropout. The TV that drops out last is the winner.

My Sony TVs have good tuner sensitivity with my indoor antenna. What brands are you using?

A better antenna, a better antenna location, or a preamp might help with your problem channels. Another alternative is to buy an external tuner, like the Channel Master 7004, for your new TV.
https://www.avsforum.com/forum/186-c...erter-box.html

If you can not measure it, you can not improve it.
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www.megalithia.com/elect/aerialsite/dttpoorman.html

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post #17394 of 17920 Old 09-18-2018, 03:35 PM
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Originally Posted by wiivile View Post
What would cause two TVs, one 10 years old and one brand new, to have different levels of success receiving channels with the same external indoor antenna in the same location? My brand new TV can't pick up the channels my ten-year-old TV can, with the same external indoor antenna in the same location. How can I ensure I buy a TV that can receive these channels with my antenna?

Are you simply manually unscrewing the antenna connection off the back of one tv set, and screwing it on to the other tv set and then running a scan? Or are you using some sort of antenna splitter device, and two coaxes, one running to each tv set at the same time?


It makes a difference in what exactly you are doing for this scenario.


Please elaborate a little more.
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post #17395 of 17920 Old 09-18-2018, 03:41 PM
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Originally Posted by Primestar31 View Post
Are you simply manually unscrewing the antenna connection off the back of one tv set, and screwing it on to the other tv set and then running a scan? Or are you using some sort of antenna splitter device, and two coaxes, one running to each tv set at the same time?


It makes a difference in what exactly you are doing for this scenario.


Please elaborate a little more.

Simply manually screwing and unscrewing and running a scan each time it is screwed/unscrewed.
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post #17396 of 17920 Old 09-18-2018, 03:57 PM
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Simply manually screwing and unscrewing and running a scan each time it is screwed/unscrewed.

Ok, then Rabbit is 100% correct with his info.
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post #17397 of 17920 Old 09-18-2018, 04:06 PM
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Quote:
Originally Posted by rabbit73 View Post
The sensitivity of TV tuners can vary a lot. Unfortunately, there are no published tuner sensitivity test results to guide you.

The ATSC has published tuner sensitivity guidelines, but they are not mandatory.

ATSC Recommended Practice:
Receiver Performance Guidelines
Document A/74:2010, 7 April 2010

RECEIVER PERFORMANCE GUIDELINES



When the digital to analog converter boxes (CECBs) came out 10 years ago, they had to meet government specs to qualify for the coupon program, so they had the best tuners for OTA. Slowly, the TV tuners became just as sensitive.

Now, the pendulum is swinging in the other direction. The TV manufacturers aren't concerned about OTA tuner sensitivity because most users have their TV connected to a cable box with an HDMI cable. Even worse, some "TVs" don't even have a tuner. They are called displays; we used to call them monitors.

The only way to be sure is to test a TV before buying.

The way I test tuner sensitivity is to set up two TVs with a splitter and a variable attenuator. I increase the attenuation to make the signal weaker to the point of signal dropout. The TV that drops out last is the winner.

My Sony TVs have good tuner sensitivity with my indoor antenna. What brands are you using?

A better antenna, a better antenna location, or a preamp might help with your problem channels. Another alternative is to buy an external tuner, like the Channel Master 7004, for your new TV.
https://www.avsforum.com/forum/186-c...erter-box.html

Thanks. Old TV is a Panasonic TC-32LX34. New TV is a TCL 55R617.


I'm surprised that - given how thorough TV review are these days on sites like Rtings - no attention is given to TV tuners. With cordcutting being in vogue, I thought the number of people relying on OTA signals + Netflix would be increasing.


I've already returned the TCL tv for its tuner performance and unrelated LCD-related quality issues, but I'm scared to buy something else knowing that tuner performance can vary so much. I didn't know an external tuner was an option though, thanks. Less than ideal but it may save an otherwise great TV from a poor tuner?
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post #17398 of 17920 Old 09-18-2018, 05:52 PM
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Others might (hope) they chime in but I would recommend either an LG or Samsung. Their tuners are known to be very good.

Nick

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days I've stayed alive. - George Carlin - 1996
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post #17399 of 17920 Old 09-19-2018, 01:46 AM
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Sorry if this has been posted already...

Does anyone have any experience/ tech info on the new Kitz Tech UHF antenna(s) and how they compare to the DB8-E and alike?


http://www.kitztech.com/products.html
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post #17400 of 17920 Old 09-19-2018, 05:01 AM
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Quote:
Originally Posted by onwisconsin View Post
Sorry if this has been posted already...

Does anyone have any experience/ tech info on the new Kitz Tech UHF antenna(s) and how they compare to the DB8-E and alike?


http://www.kitztech.com/products.html
I'd suspect it's impossible to do a direct comparison based on the very sketchy "specs" provided. A "total" of 34 dB of gain might be from a 36 dB amplifier and a -2 dB antenna (extreme example). Since he used the same photo for all three variants and the physical dimensions are listed as being the same at about 21" tall, 26" wide, and 5"deep, I'd place the antenna portion itself as roughly equivalent to an Antennas Direct C2V (or newer C2 Max) without the reflectors. His VHF elements might perform a bit as reflectors for the UHF loops so there might be a slight F/R ratio.

No comparison to an 8-bay, a 4-bay, or any conventional stick antenna that is over 3' in length.

Last edited by ProjectSHO89; 09-19-2018 at 06:46 AM.
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