Any "modern" TV techs here? Please look inside. (Page 1/2)
Raydar NOV 09, 06:48 PM
Is there any way to read RSSI on an older Samsung LCD TV? I already found the service menu access, but I don't want to brick anything. It's not intuitive at all.
(Trying to get my non-rotating directional antenna dialed in. It's right on the ragged edge, on just one station. Others are quite good.)
theogre NOV 09, 08:47 PM
Do Not mess w/ the TV. Wrong target for the problem.

Exact antenna used?

Most TV stations "numbers" are meaningless now because of FCC.
Look up the real RF channels for your area at https://www.antennaweb.org/

Why?
Stations still use same bands, VHF Low (2-6), VHF Hi (7-13), and UHF, but many moved and still moving to new channels.
Worse, Many "digital" TV Antennas only pick up UHF. Some may pick up VHF Hi too if very local.

VHF Low nearly always going to need a big to biggest antenna. And more so now because Digital TV drops signal way easier and FCC drops power output for most broadcasters.

See https://www.youtube.com/c/AntennaMan

Then on top of that....
Many coax cables or most come w/ whatever junk antennas are crap too loosing signal, allowing noise, etc.
Even w/ good cables, can't just Finger Tighten the ends to get good signal.
If Hex "nuts" use a small 7/16" wrench to tighten that last fraction of a turn.

------------------
Dr. Ian Malcolm: Yeah, but your scientists were so preoccupied with whether or not they could, they didn't stop to think if they should.
(Jurassic Park)

The Ogre's Fiero Cave

[This message has been edited by theogre (edited 11-09-2021).]

Raydar NOV 09, 09:37 PM
I get it. I've been doing telecom for 40+ years, including public safety radio and microwave. I'm not exactly green at this.
The only channel I'm having issues with is channel 5. (Which happens to fall on RF channel 27, here.) I'm ~50 miles southwest of Atlanta. All the stations I'm interested in are essentially in the same direction, give or take a very few degrees. It's *very* close. But I figure that if I have an RSSI reading, I can get it as good as it can get, without raising the antenna or buying a larger one. (Not off the table.)
The antenna I'm using is a fairly basic rooftop antenna. But a nearly identical antenna worked just fine at my old house. I was only ~2/3 the distance but the signal path was much worse than the present. I was down in a hole with no line of sight at all. (The technical term for the path was, IIRC, "two edges".)
BUT... I found some Atlanta FM stations that are like 1/2 mile from the TV transmitter in question. I might be able to use the signal strength meter on my stereo receiver, and accomplish what I need.
But thanks for your input. You were most helpful.

[This message has been edited by Raydar (edited 11-09-2021).]

theogre NOV 10, 11:26 AM
Getting signal "meter" in a TV is ok. Many will mess w/ the TV itself and make a problem far worse.

Lower FM radio is in upper end of VHF Low so might help. FM didn't get power limit dropped like many TV stations did.
(Is why many FM had minor mods or made from factory to pick up analog VHF audio.)

Even when have same distance and direction to whatever station...
FCC dropped many station output limits and what was good for a station to covering X miles now can't because of new power limits.

FCC sold Digital TV as "Best for You" is 100% BS for many markets.
FCC want to shrink more and more even now because They want to shrink TV spectrum to resell to others.
Then add many Stations has compressed most or all sub channels often including x.1 to the max so many look bad on big screens even if you get a good signal.
Because Many Sub channels are Money Generators for the stations because is paid content by others.
ray b NOV 10, 09:39 PM
I am a bit far south of the stations here

and find a small but good quality ant amp can really help weak stations

note I am sure you two know but for others reading this
you do not need a digital amp ant or any other bits [other then a tuner] for OTA digital tv
or HD tv the old stuff works fine
theogre NOV 11, 10:46 AM

quote
Originally posted by ray b:
I am a bit far south of the stations here

and find a small but good quality ant amp can really help weak stations

note I am sure you two know but for others reading this
you do not need a digital amp ant or any other bits [other then a tuner] for OTA digital tv
or HD tv the old stuff works fine

Yes, I do know...

Nearly All Antennas w/ "Digital" label is a scam and most made Very cheap too.

Even w/o "Digital" label Most small ones are description as above...

Side Note: Digital TV Switch wasn't first time FCC shrunk TV bands but has a bigger effects.
In 1983 FCC eliminated 70 to 83 UHF channels that forcing Stations and/or the Repeaters/"Satellite" they use to change channels or eliminate Repeaters
after Digital switch FCC got Many Billions of $ to resell TV spectrum to Cell Phone Carriers...
2009 eliminate 52 to 69
2011 eliminate 51
2019 eliminate 38 to 50
(From https://en.wikipedia.org/wi...evision_broadcasting )

FCC wants all Broadcast TV die for Cable Operators. Many wants AM radio to die too. Example: FCC’s plan to go digital will kill AM radio
And Digital "HD AM" isn't first failure to "update" AM... AM Stereo failed in the 1980's and 90's w/ many early stereo stations giving away radios for whatever format they used. No car markers install any AM Stereo radios that I know of. Near No-one bought them either because of high cost and multiple incompatible formats.
Raydar NOV 16, 08:37 PM
Heh... Found something that is even better than the RSSI reading.
It's a tiny spectrum analyzer that covers 10KHz to 900+ MHz.

https://www.tinysa.org/wiki/

On the display, a digital TV signal looks like an 8MHz wide "plateau". The first thing I noticed is that the low end of the channel in question had more amplitude. As I turned the antenna, the plateau balanced out, and the signal strength also seemed to increase just a tiny bit. (Not sure of the "nuts and bolts" of this, since my methods are very primitive, but it did work.)

You have to be careful to not use it near any transmitters, lest you overload it or burn out the receiver front end, but otherwise it does exactly what I needed.
Essentially, what it told me is that my antenna was off axis, to receive the one major station that I wanted, but by zeroing that one in for the best signal, I lost several others. (This is puzzling, because there are only like 3 degrees between any of the Atlanta stations, and the antenna is not that selective. Can you say "ragged edge"?)
So it looks like I need to add another ten feet of pipe (easy), or maybe buy an antenna with more gain. (Right now, at ~50 miles from the station, the antenna just peeks over the ridge of my roof. The signal I zeroed in on is at -80 to -85 dB. I can do better than that.)

Some people may suggest using a preamp. And that's also a possibility. But the use of a preamp pre-supposes that you actually have enough signal to work with, in the first place. If not, you'll be boosting what little signal there is, but you'll also be boosting any competing interference or other background noise. Again... "ragged edge". Going to raise the antenna.

[This message has been edited by Raydar (edited 11-16-2021).]

maryjane NOV 16, 09:01 PM

quote
(Right now, at ~50 miles from the station, the antenna just peeks over the ridge of my roof.



How high is the ridge of your roof?
Raydar NOV 17, 06:47 AM

quote
Originally posted by maryjane:

How high is the ridge of your roof?



Only about 20'. But the same height, with a similar antenna, was plenty at 30-35 miles. ("Ragged edge". )

FWIW, this is one of the tools I used to locate where to point the antenna.
https://www.rabbitears.info/searchmap.php

I usually enter LAT/LON info (I'm told that address search does not work - YMMV - but a Google Map search of your address will allow you to pinpoint that.
The suggested search distance is 100 miles.
The default antenna height is 30', but it can be changed, too.

[This message has been edited by Raydar (edited 11-17-2021).]

Raydar NOV 17, 07:36 PM
Annnd an update...
Stuck another ten feet of pipe to the antenna mast.
It actually became too unwieldy to handle (I'm using chain link top rail) so it ended up being only six or seven feet of additional height.
But that made all the difference. I found all of the major market stations, and a bunch of secondary stations. Even the ones that I lost by aligning to my spectrum analyzer, yesterday.
So yeah... I'm quite happy. I'm going to let this run for a couple of days and make sure I don't lose anything I'm especially interested in, and then hook it up to the rest of the TVs in the house.
If it still continues to work out, I'll tel DirecTV to stuff it.
This is only a stop-gap, until our fiber is installed and I can stream other stuff, but this will do nicely in the interim.

If anyone has any questions, I'll be happy to share what I can.