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The Official AVS Antenna and Related Hardware Topic! - Page 471

post #14101 of 15454
The Comcast head end for the Norwich franchise is located on Plain Hill road, just south of Baltic Connecticut, also known as the town of Sprauge.

The tower was originally built back in the mid 1980's to pull in New York City stations WPIX VHF CH. 11 and WWOR VHF CH. 9 from Seacaucus N.J.

Both stations have since been removed when it was determined WWOR was getting co-channel interference from tropo and WPIX was eventually picked up off of a satellite feed, when WPIX became a super station, but brfore that WPIX was watchable about 70% of the time due to WBAL CH 11 from Baltimore MD causing tropo most of the time.

WPIX became an affiliate of WB and it was dropped because WCTX WB-59 was the local WB affiliate for our market area.

They also dropped WLVI 56 Boston because it was also an WB affiliate.

We also lost WSBK 38 Boston because it became an affiliate of UPN and so did WTXX (now called WCCT) Ch.20 from Hartford.

So as you can see, many channels were lost do to network affiliation.

I forget now how tall the head end tower is, they originally used telephone poles with various antennas perched on top until they get zoning permission to construct the tower they now use.

It took a lot of local meetings to get that tower put up to get those two stations from the New York city area added to our system.

I am guessing but it might be at least 300 foot maybe taller.

Now true we do get WCVB 5.1 Real 20.1, but they also black the station out occasionally with a computer generated memo stating the following, "Do to FCC regulations this station must be blacked out" this is because WTNH 8.1 real 10.1 from New Haven is our local television market ABC affiliate.

So what this means is WCVB Boston which is also ABC, is only carried (Not blacked out) when there are no scheduled network feeds from the ABC network.

Comcast in Norwich used to have 19 OTA stations in its line up.

Now it carries 12 OTA channels between channels 2 through 18 on their system as its basic package, now for each station that carries digital sub channels, Comcast has conveniently placed those channels up in the 700's requiring the rental of one of their SA digital converter boxes in order to view those sub channels.

In my opinion, if those channels are feed over the air for free, they should be included as part the bare basic channel package.

This would include channels such as This TV, US, Create and CPTV4u The last two channels are broad-casted on Norwich's WEDN 9.2 and 9.3.

WFSB and WVIT have subs carried up in the 700's as well, so you have to purchase the "digital preferred" package to get those subs that broadcast in 4.3 format!

By the way while on the subject of digital TV I am glad to see WJAR picked up MeTV and dropped RTV.

MeTv carries most of the same shows as RTV but, has a larger library than RTV in its broadcast schedule.

If you can get WJAR 51.2 from Providence check out their line-up.

Bruce.
post #14102 of 15454
Quote:
Originally Posted by kenglish View Post

Looks like the two stations are about 90-degrees from each other at Norwich. There are some pretty elaborate ways to do this, using yagi antennas and other, highly-directional antennas.
It's also possible to use shielding (buildings, etc), by carefully positioning the antennas...and, hoping nobody builds anything close by that would reflect an unwanted signal in to the antenna.

I removed all of your links to save space, but it would be quite interesting to make an attempt to duplicate and build a home made version of those antennas you linked me to.

I am sure those antennas are for commercial purchase only and are more than likely quite expensive to purchase.

Although I have seen one antenna on solidsignal's web site listed for $700.00 and it was a single channel VHF antenna. Imagine a home owner buying something that expensive to receive one channel.

This particular one here is an interesting mass of aluminum and would be quite a project to copy.
http://www.kathrein-scala.com/catalog/PR-TV.pdf I am curious where the feed line attachs on this one.

Although this one would be a bit of a challenge as well: http://www.lindsaybroadbandinc.com/P..._Parabolic.pdf

Just need a good supply house that sells materials suitable for making television antennas.

Bruce.
post #14103 of 15454
Quote:
Originally Posted by MrBruce View Post

This particular one here is an interesting mass of aluminum and would be quite a project to copy.
http://www.kathrein-scala.com/catalog/PR-TV.pdf I am curious where the feed line attachs on this one.

The feedline is attached on the back.
LL
post #14104 of 15454
And from the back, the signal would be applied to the (second from front)
Active Dipole in the 2-element Yagi (forward most is Yagi's reflector).
The 2-Element Yagi points toward the large reflector.
post #14105 of 15454
Quote:
Originally Posted by rabbit73 View Post

My post about Noise Margin had a LOT of words.

The situation is actually somewhat worse then that because you need to factor in receiver Noise Figure (NF). During testing the FCC put that at about 7 dB. So receive signal must be that much stronger to be decoded.
post #14106 of 15454
Quote:


And from the back, the signal would be applied to the (second from front)
Active Dipole in the 2-element Yagi (forward most is Yagi's reflector).
The 2-Element Yagi points toward the large reflector.

Yep.

The gain claim of 15.5 dBd at 470 mhz seems bogus to me. Its a 68" X 36" X 18" partial parabola. The 84" full parabola CM-4251 doesnt have gain that high on the lower uhf channels. (and from my CM-4251 modeling, CM's dBd is only a bit higher than dBi, but back then they were using advantageous test beds, heh)

Edit: Never mind, now I see its a SINGLE channel antenna that uses the same reflector for all uhf channels, and the driven element is customized for that one channel.
The upward scaling gain curve would lead one to believe its a broadband antenna, heh.
post #14107 of 15454
Quote:
Originally Posted by Tschmidt View Post

The situation is actually somewhat worse then that because you need to factor in receiver Noise Figure (NF). During testing the FCC put that at about 7 dB. So receive signal must be that much stronger to be decoded.

Yes, that is especially true if you don't use a preamp.

However, if you do use a preamp at the antenna, the overall system NF is much better, because of the lower NF of the preamp. See the Cascaded Noise Figure discussion here:

Signal Amplifiers (Amps, Preamps, Distro Amps) - See Chart in Post #1
www.digitalhome.ca/forum/showthread.php?t=42426

and this post by majortom for 4 different scenarios:
www.digitalhome.ca/forum/showpost.php?p=1218150&postcount=2446

A preamp makes a big difference with my 50 ft coax downlead.
post #14108 of 15454
Quote:
Originally Posted by rabbit73 View Post

However, if you do use a preamp at the antenna, the overall system NF is much better, because of the lower NF of the preamp.

Absolutely agree, a good low noise preamp dramatically reduces effective noise figure. Has the same effect as getting an antenna with more gain.

Just to be clear we are not talking about preamp gain. NF is the amount of noise added to the signal. The more noise the greater the receive signal strength needs to be to overcome it.
post #14109 of 15454
Quote:


Has the same effect as getting an antenna with more gain.

I think a more apt way of putting it would be
"Has the same effect as getting an tuner with better sensitivity and less noise".
post #14110 of 15454
Quote:
Originally Posted by 300ohm View Post

I think a more apt way of putting it would be
"Has the same effect as getting an tuner with better sensitivity and less noise".

I think the antenna analogy is more accurate IF, as should > be, the low noise preamp is at the antenna before the 300ohm cable ... or 75ohm coax. There is a reason the LNA is at the antenna on dishes ...
post #14111 of 15454
Both a better antenna and a preamp can give more gain, but the antenna also improves the SNR (because of its directivity), while the preamp makes the SNR (at the preamp output) worse because its own noise (NF) is added.

The preamp makes up for its added noise because it improves the overall system NF because it is at the head-end (before downlead and splitter losses) which takes precedence in the total system NF calculation.

Or, as some people say it, the preamp NF (hopefully lower than the tuner NF), not the tuner NF, determines the total system NF.

Take another look at majortom's 4 examples at Google Docs where he gives the system NFs:
docs.google.com/spreadsheet/ccc?authkey=CPbi9aYO&key=0Alk4YjsB3lG6dEVOT0d5eFZlZnVrN2poRTVIalpwT3c&hl=en&authkey=CPbi9aYO#
post #14112 of 15454
CM4221HD (New) 4-Bay Bowtie with Balun Hack Modification:

I posted 4nec2 simulation results at fol. webpage (incl. 4nec2 source file):
http://imageevent.com/holl_ands/mult...uhfnewcm4221hd
Measurements were from information posted by and Balun Hack details
derived from a photo posted by (see results webpage for thread references).

UHF Raw Gain=12.2-15.3 dBi. UHF SWR(300) under 2.1.
UHF F/B Ratio=19-33 dB and UHF F/R Ratio=15-18 dB.

Hi-VHF Raw Gain=3-6.6 dBi (FORWARD), but HIGHER Hi-VHF Raw Gain=7.7-5.0 dBi
(TOWARDS REAR!). Hi-VHF SWR(300)=EXCESSIVE, esp. on lower Hi-VHF channels.

UHF Raw Gain:
http://photos.imageevent.com/holl_an...Raw%20Gain.jpg

UHF SWR (300-ohms):
http://photos.imageevent.com/holl_an...nder%202.1.jpg

Hi-VHF Raw Gain - Higher towards the REAR (Azi. = 270-deg):
http://photos.imageevent.com/holl_an...0to%20REAR.jpg

Hi-VHF SWR (300-ohms) - EXCESSIVE, esp. on lower channels:
http://photos.imageevent.com/holl_an...0EXCESSIVE.jpg

Although NEW, CM4221HD is still optimized for OLD UHF Band (up thru Ch69),
wasting Max Gain peak on channels that are no longer available for DTV.
UHF Raw Gain is about same as older CM4221 with improved UHF SWR on
lower channels....and Hi-VHF Raw Gain & SWR, such as it is, has been degraded....

Super-Sized-4-Bays have better Gain on New UHF Band (up thru Ch51) and
don't have a Hi-VHF Gain Reversal problem.

BTW: I don't think the NEC2 Engine has sufficient accuracy to model the
capacitive coupling problem caused by the Balun Feedlines being too close to
the vertical support beam in the "as-shipped" CM4221HD configuration.
post #14113 of 15454
holl_ands:

Thanks for doing the modeling on the new CM4221HD.

I turned the strips between the two inner bays over to make my measurements so that I could put them back the original way if needed for more measurements. The balun sticks out too far, especially with the added spacers. If I have more time, I will replace the bowed out strips with straight strips for the balun and repeat my measurements. I will, however, still raise the balun above the strips with spacers to maintain the balun feed at the midpoint where it should be. After the balun mods and removing the caps, the new 4221 beats the orig 4221. I don't think it is a good idea to modify the reflector, unless you are in a strong-signal market that requires a wider azimuth coverage so that you don't have to use a rotator.



More details about my tests of the CM4221HD here:
www.digitalhome.ca/forum/showpost.php?p=1167870&postcount=221

I still haven't figured out why removing the black plastic caps that cover the connections where the whiskers connect to the feedlines makes such a big difference, but my measurements say that it does. The only thing I can think of is that they contain a metallic compound for UV protection that acts like an electrostatic shield without having any electrical conductivity.

I noticed a similar property in metallic paints (that have suspended metallic particles) used on vehicles that have HF mobile antennas. It makes a big difference in the measured ground path loss, which is a series resistance in the antenna system from the vertical vehicle antenna > thru the air > thru the metallic paint > to the metal car body.

Yes, the CM design wastes a lot of potential gain at the low end. Is there a world market for an antenna used above CH 51 (698 MHz) or don't they know any better? Maybe they think that 2 or 3 dB at the low end doesn't matter, or maybe they didn't want to make a bigger antenna that would require a bigger box!
post #14114 of 15454
Quote:


Is there a world market for an antenna used above CH 51 (698 MHz)

Yep, there still is until about 2020 ? El Salvador may not be switching until 2019, heh.

http://en.wikipedia.org/wiki/Digital...ion_transition
post #14115 of 15454
Europe, Australia and many other countries have, until just recently, used UHF frequencies
up to 860 MHz, much higher than our old max of Ch69 (806 MHz). [Our new max is 698 MHz.]

In Europe, the 790-854 MHz band is being cleared of TV signals, making it available
for other purposes. They are also proceeding to allow White Space Devices to operate
in and amongst the remaining TV channels (sound familiar????):
http://www.inets.rwth-aachen.de/file...ite-Spaces.pdf

See fol. Wiki article, although I can't vouch for whether it's up to date or not:
http://en.wikipedia.org/wiki/Televis...el_frequencies
Note that many times the CENTER frequency is listed...and sometimes NOT.

FYI: Europe frequently uses "Band IV" and "Band V" to describe UHF Antennas,
but the definition of which frequencies lies in each band can vary quite a bit:
http://en.wikipedia.org/wiki/Band_IV
http://en.wikipedia.org/wiki/Band_V

Ireland is no longer using Band I (Lo-VHF) and I suspect many others are
vacating this problematic band (unconfirmed). Band II is FM, which is planned to
be replaced by DAB (or equivalent) digital voice/music, now in Band III (Hi-VHF)
or in a much higher group in the L-Band (depending on the country).....or maybe
within the DVB-H (Handheld) digital streams.....I haven't kept track of all of the
zigs and zags in the various country discussions.....

So far, DAB broadcasts haven't been given sufficient capacity, so they are
overcompressed, sounding WORSE than FM Stereo:
http://www.digitalradiotech.co.uk/da...b-h_vs_dmb.htm

So current "state-of-the-art" suffers from the same complaints I have wrt
Internet Music and HD-Radio. I'll REALLY be disappointed when "they" phase
out (hard to get) SACD/DVD-A....and (not too long from now)....CD's....
post #14116 of 15454
Quote:
Originally Posted by holl_ands View Post

..I haven't kept track of all of the
zigs and zags in the various country discussions.....

So far, DAB broadcasts haven't been given sufficient capacity, so they are
overcompressed, sounding WORSE than FM Stereo

So current "state-of-the-art" suffers from the same complaints I have wrt
Internet Music and HD-Radio. I'll REALLY be disappointed when "they" phase
out (hard to get) SACD/DVD-A....and (not too long from now)....CD's....

Zigs and Zags - That's for sure, even here in the US we can't seem toget spectrum management right. Reference the Light Squared trying to share frequencies with GPS fiasco. Sheesh - who came up with that idea and why is the Government even letting that be discussed. Someone powerful must have skin in that game based on the testimony I've heard before Congress lately. I work with guys doing GPS-OCX development, and the concerns coming from that community ... Wow, glad I work on a weather satellite program.

Gosh, I didn't even know SACD was still around - it seemed like the perfect media for classical music - my fav, maybe its more common in Europe? I love good audio and video. With my 42 in Panny plasma, there are times when I can tell the difference between something on Blu-Ray and "HD" broadcast OTA and/or the cable. Full bandwidth video is pretty amazing to see - especially nature videos.

Wouldn't it be nice to have an antenna test range with appropriate, calibrated test equipment? Then we could put these antennas through their paces and verify manufacturer claims. I can get my hands on a spectrum analyzer from work, but alas no signal generator. *sigh*.

Oh well.
post #14117 of 15454
I'm trying to decide the best way to improve reception and would appreciate your suggestions. I have a small (but pretty good) antenna (picture below) in my attic with a passive 2-way splitter to TVs in the living room and bedroom. I receive 10 local stations (total 26 sub-channels) with distance to the towers ranging from 15 to 37 miles. And, I prefer to keep the antenna in the attic, rather than on the roof.

Only one station is indicating 100% signal strength on my CM-7000PAL. Four are 85-91% and five are 78-82%. Those five are normally solid but can be marginal, with occasional momentary pixelation during certain weather conditions.

If I remove the splitter the signal strength to the living room goes up another 4% to 5%.

Would I be better off by installing a larger antenna, a pre-amp for the existing antenna, or adding a second small antenna to avoid using a splitter (each TV would then have its own antenna)?

AJ
LL
post #14118 of 15454
Quote:
Originally Posted by A J View Post

Would I be better off by installing a larger antenna, a pre-amp for the existing antenna, or adding a second small antenna to avoid using a splitter (each TV would then have its own antenna)?

AJ

It depends on the mix of VHF & UHF, the relative strength of the stations, plus the azimuth variation between them.

Because you already have the splitter in the attic a second antenna is easy.

To use a preamp get a one port power passing splitter instead of the one that you have now. That allows the power inserter to be behind one TV set.
post #14119 of 15454
Some comparisons...clearly a Preamp is better than Two Antennas...or even a Better Antenna(s):

1) Current Configuration Assumptions: System Noise Figure = 15.4 dB.
System NF = Simple Sum of Losses: Balun=1.5 dB, Balun-Splitter Coax=0.5 dB (10-ft RG-6),
Splitter=3.5 dB, Splitter-TV=2.7 dB (50-ft RG-6) & Tuner NF=7.2 dB ("typical CECB").

2) Two Separate Antennas: System Noise Figure = 11.9 dB.
System NF = Same as #1 except without Splitter Loss.

3) If Add a Preamp:
CM-7777 (28 dB Gain): System Noise Figure = 4.4 dB.
W-G AP-4700 (19 dB Gain): System Noise Figure = 5.0 dB
W-G HDP-269 (12 dB Gain): System Noise Figure = 6.8 dB

See "COMPARE System Noise Figure" & "DTV Preamp Signal Overload Calculator":
http://imageevent.com/holl_ands/files/ota

Which Preamp is appropriate for you can be determined using my OVERLOAD
Calculator Spread Sheet (see signature), presuming a guesstimate for
how much signal loss is due to attic location (I estimate 13 dB +/- 7 dB..or more).
"Satellite" RF Splitters are nearly always DC PASS on one or both ports.

High Gain CM-7777 is only suitable for RURAL locations...but attic loss might be enough...
W-G AP-4700 has lower Gain and NO Gain for VHF (VHF Gain is rarely needed).
W-G HDP-269 has the least Gain...and least likely to "overload".
"Overload" is actually desensitization on certain channels due to Intermodulation Noise...

As always, it helps if we could see your TVFool Results....
post #14120 of 15454
Quote:
Originally Posted by holl_ands View Post

As always, it helps if we could see your TVFool Results....

Here's the TVFool. My antenna is about 12 ft AGL and aimed to 330 deg (after quite a bit of shifting position in the attic to find the sweet spot). I don't receive WNSC but, no big loss there since I get two other PBS stations. My antenna is high-vhf/uhf since WTVI is VHF. That station is also my TVGOS source.

AJ
LL
post #14121 of 15454
Quote:


..clearly a Preamp is better than Two Antennas...

AJ, that should be rephrased as a QUALITY preamp is better than two antennas.

Some of the preamps/distribution amps commonly available locally at RS, Lowes, Home Depot, Walmart etc are noise making overload champs, causing more problems than they solve, heh.

The HDP-269 holl_ands mentioned above should be your least cost safest bet. The only thing bad Ive seen about it in the reviews is that the wall wart power supply may die too early.
post #14122 of 15454
Quote:
Originally Posted by 300ohm View Post

AJ, that should be rephrased as a QUALITY preamp is better than two antennas.

Sounds like a preamp is the way to go, and fairly painless at less than forty bucks with free shipping from amazon for a couple of the model preamps mentioned.

My simple 2-way splitter will have to be replaced with one designed to pass through power to the preamp. Any suggestion for a brand or specific model (hopefully also carried by Amazon to simplify things).

AJ
post #14123 of 15454
Quote:
Originally Posted by A J View Post

Sounds like a preamp is the way to go, and fairly painless at less than forty bucks with free shipping from amazon for a couple of the model preamps mentioned.

My simple 2-way splitter will have to be replaced with one designed to pass through power to the preamp. Any suggestion for a brand or specific model (hopefully also carried by Amazon to simplify things).

AJ

Since you only have ONE strong signal, W-G AP-4700 would probably provide slightly better,
performance....unfortunately, Amazon only stocks "similar" AP-8700 with 17 dB VHF Gain.
It's the same price and the extra VHF Gain should help rather than hurt Ch11 reception.

Although antennahacks did some comparison tests on 2-Way Combiners for Antennas,
I have not seen any tests for SAT 2-Way RF Splitters (typ. 2+ MHz).

Sat RF Splitters on Amazon:
Audiovox DH24SPR (aka RCA DH24SP, DC PASS Both Ports)
"2 GHZ" from (overpriced) Monster Cable (specs???)

Following high quality, affordable SAT RF Splitters are usually stocked by various
Home Supply stores:
RCA DH24SP (DC PASS on Both Ports) [maybe Amazon or Sears: photo is wrong]
GE 87623 (DC PASS on Both Ports) (Home Depot)

Searching will also reveal sources for fol. quality parts:
Steren 201-242 (DC PASS on Both Ports) (e.g. Summit Source, Sears)
post #14124 of 15454
Quote:


GE 87623 (DC PASS on Both Ports) (Home Depot)

Yeah, I saw that at Home Depot. It really wasnt much more than their non pass thru splitters.
post #14125 of 15454
I have been reading the posts about the definition of Noise Margin and I don't see any mention about the TV receiver bandwidth which would affect the SNR. Is it assumed that the TV receiver is using a matched filter when you do a noise margin calculation? I would assume a practical bandpass filter along with the mixers image rejection capability would slightly degrade the SNR.
post #14126 of 15454
Yes, you are correct in assuming that the receiver bandwidth affects the SNR. It needs to be wide enough for proper reception of the selected channel, but no wider.

If you mean the channel bandwidth inherent in the tuner design, that must meet certain specifications for desired to undesired signals as in this document:
NTIA Coupon-Eligible Converter Box (CECB) Required Minimum Performance Specifications and Features
edocket.access.gpo.gov/cfr_2010/octqtr/47cfr301App1.htm

Scroll down to sections 10 thru 12.

See also ATSC Recommended Practice:
Receiver Performance Guidelines

www.atsc.org/cms/index.php/standards/recommended-practices/180-a74-receiver-performance-guidelines
which gives a link for this:
www.atsc.org/cms/standards/a_74-2010.pdf

If mean an external bandpass filter, then it would not affect the SNR in the 6 MHz channel, but it would improve the overall SNR if the noise floor was high (an in VHF-lo) to cause an increase in noise adjacent to the received signal.
post #14127 of 15454
Quote:


I have been reading the posts about the definition of Noise Margin and I don't see any mention about the TV receiver bandwidth which would affect the SNR.

If youre talking about TVFools NM, then no, it doesnt take into account defective or out of spec tuners.
post #14128 of 15454
Quote:
Originally Posted by 300ohm View Post

If youre talking about TVFools NM, then no, it doesnt take into account defective or out of spec tuners.

I used to be a radar systems engineer and there were 4 terms in the radar range equation (K, T, B, and NF) that set the noise floor that limited how far away you could detect a target. I was just wondering how B, the noise bandwidth, affected the performance of the ATSC receiver.
post #14129 of 15454
Quote:
Originally Posted by retiredengineer View Post

I used to be a radar systems engineer and there were 4 terms in the radar range equation (K, T, B, and NF) that set the noise floor that limited how far away you could detect a target. I was just wondering how B, the noise bandwidth, affected the performance of the ATSC receiver.

There are (at least) three Bandwidths of interest wrt Receiver Sensitivity.

1) Transmitted Signal Bandwidth: It is just over 5.38 MHz wide with a relatively FLAT
frequency response, except unmodulated Pilot Tone, with a higher spectral level:
http://www.axcera.com/downloads/tech...technote_9.pdf
www2.rohde-schwarz.com/file_12015/7BM102_0E.pdf
Note that "Nyquist" 5.38 MHz Bandwidth is TWICE the symbol rate frequency.

This barely fits within the 6 MHz allotted channel bandwidth with room for
frequency roll-off to the adjacent channel in the Transmit Mask Filter as well
as the Receive IF Filter. Of course, 6 MHz was chosen to maintain compatibility
with concurrent old Analog channel assignments. In former PAL/SECAM countries
they use 7 and 8 MHz channel bandwidths...and hence can use higher DTV data rates.

The fol. paper analyzes the many factors that can DEGRADE the Transmitted
(and Received) SNR:
http://www.broadcastpapers.com/white...in%208-VSB.pdf

2) RF Front End Bandwidth: Typically 3 dB down by 20-30 MHz from Center Freq,
with a mild slope across many adjacent channels....many tuners showed
susceptibility 14-15 channels away due to insufficient image rejection.
A strong signal on nearby channels will desensitize the desired channel
due to the Automatic Gain Control (AGC) reducing RF (and IF) Gain to prevent
the nearby signal from overloading the tuner....

Double Conversion Tuners "typically" do not use Tuned RF Amplifier stages,
relying completely on the bandwidth rejection in the First & Second IF Stages.

3) "Detection" Bandwidth: This is what is usually used to determine the output SNR.
In a DTV Receiver this is usually the Bandwidth of the IF Amplifier, although some
ATSC Decoder Chips are designed for use in a Direct Downconversion to Baseband
type Receiver, where the final, even narrower band Digital Filter is within the
Chip....in which case it will be closer to 5.38 MHz.

I haven't yet found the right document re how to "correctly" measure SNR,
but I THINK that they ignore the 0.3 dB of (average) power in the Pilot Tone,
so the averaged spectral level of the signal can be compared to the averaged
spectral level of the Noise Generator when setting SNR for a test run.
post #14130 of 15454
@holl_ands, thank you for your detailed response. I have placed a copy of it in my ATSC folder.
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