Signal Splitters That Block TV Signals..
HTML-код
- Опубликовано: 10 сен 2024
- tvrepairinform...
When I first started doing TV antennas I didn't realize there was any difference between a signal splitter used for over the air Antenna TV signals, and a diplexer, which is used with satellite signals, and I quickly discovered the DC pass through side of the diplexers used for satellite TV prevented the TV antenna signals from passing through them. In this video I explain in more detail what I learned as a result. If you look at the specifications on the splitters you will often see the frequencies they are designed to pass.
==============================================================================
HERE ARE THE NAMES OF SOME SIGNAL SPLITTERS THAT WORKED WELL FOR TV SIGNALS.
Please take note of the frequencies they are designed to pass, to make sure they are okay for your area. Here in Grants Pass Oregon nothing is broad over 700 MHZ
Amphenol BDS1202H ---This one can only pass 5 to 1218 MHZ.
Antronix CMC2002U -----This one can only pass 5 to 1002 MHZ
Regal S2DGV6 --------------This one can only pass 5 to 600 MHZ
PPC PPC-GHS-2E ----------This one can only pass 5 to 1218 MHZ
Electracord -------------------This one can only pas 5 to 890 MHZ
===============================================================================
HERE ARE SOME SPLITTERS THAT HAVE A DC PASS THROUGH THAT (DOESN'T BLOCK OTA SIGNALS).
MSPLT2R1-02 and the MSPLIT4R1-02 This splitter has 4 outputs, and one of them has a DC pass through from 2 TO 2150 MHZ
================================================================================= HERE ARE THE NAMES DIPLEXER MODEL NUMBERS (((YOU SHOULD AVOID))) FOR OVER THE AIR TV SIGNALS, AS THEY ARE DESIGNED FOR SATELLITE TV SIGNALS ONLY!
Holland HCDA-PI
Holland DP02
Holland STVC
Radio Shack 15-1847
RCA D920
You just fixed an issue in 3 minutes that I've been dealing with for years. Thank you so much.
I'm glad you found this information helpful. Thanks for the reply.
A happy Christmas from here in the UK. Thank you for the time and effort you put into your videos, they are always a pleasure to watch.
Thanks for watching Matthew. Merry Christmas.
It's also important to look at what range of frequencies the splitter is designed for. Trying to use a splitter designed for satellite (Dish and DirecTV, etc.) for OTA will not work as they typically only pass frequencies above 900MHz. Most splitters for OTA use are rated for use from 5MHz to 90MHz, and they don't typically do any DC blocking.
Good point.
Thanks Dave, I have a small box with about 20-30 multiple "splitters" in it. I use one from time to time and I will have to look more closely now.
Nice to hear from you Steve. Merry Christmas.
Merry Christmas Dave!
Merry Christmas. ;-)
Thanks a lot once again for another instructional, easy to follow video. I am always looking forward for all your new videos on OTA TV. ¡Feliz Navidad!
Glad you like them!
Merry Christmas 🎄💫❤️ and happy new year 🗓🥂
Thanks and Same to you FulvioGa
Additionally, with DTV, don't you also need to be concerned with frequency range (Mhz) and signal loss over distance? What other concerns do you have?
For sure. The frequency range of the coax is critical, and so is the length, quality and type of the coax you use , I once had a 4 foot coax jumper cause me to lose a channel due to its attenuation at a particular frequency, and there are also multipath signals also known as signal reflections can arrive at the TV out of phase with the main signal from the tower
and weaken your reception.
Glad I found another classically trained tinkerer.
Merry Christmas all :)
Hi i have an antenna with 2 leads 1 for eah bay.. i am using a straight up 5-1000mhtz 2 way splitter but in the opposite direction ...do you know if splitters are directional ?????? Thanks in adv
BTW i love maximizing my ota system🍻🍻
I think this is the problem I have. In the lounge I have all the TV channels, in the bedroom I only have about half of them but in the music room I ony have 3 channels, (sometimes 4 but they are very pixelated). As there is nothing worth watching on TV anymore, (and the TV in the music room wont retune anymore, I just use it as a monitor for various computers), I'm not bothered. :)
When I learned of youtube I rarely watched TV from that point forward.
@@GrantsPassTVRepair Same, YT is far more entertaining and educational. Plus you get to choose what you want to watch and when.
if you aim the diplexers toward one another they will allow dc pass through and your signal to your second tv but you will need to have another two way splitter not diplexer to catch your third tv..... Or allow dc pass through from tv three to the other diplexer at tv one where they must be aimed toward one another to pass dc and signal simultaneously and then use a two way splitter to reach your second tv!! if you need more info please feel free to reach out i have about 20 plus years in satellite and cable work!!
That was very informative and thanks 👍👍 However, and not knowing where you are located, I am in Central Ontario Canada just west of Toronto and we don't seem to receive OTA signals anymore. I did a google search which didn't seem to help much of potential signals.
Any thoughts on this?
Some three-way splitters attenuate 5.5db per output while some are a two-way going into a second two-way and split the signal 4db, 7db, 7db.
The second one is only good where the first of the three lines going out is much longer than the other two.
Thank you for the tip on the splitters and db losses, but I can't quite follow what you're saying. Can you clarify?
@@GrantsPassTVRepair I'm using a similar 3 way splitter. Two ports are marked -7dB, one port is marked -3.5dB. So it's essentially a two way splitter with one of those out ports feeding another two way splitter. I use the -7dB ports to feed the main TV and a Tivo DVR in the same room. The -3.5dB port feeds an 80' run of coax that goes to a bedroom.
Hey Dave.
I didnt realize that. But i have a different question for you.
I am looking for an indoor FM antenna that will really pull the stations in. I live in town with neighbors houses very close by and lots of trees in the area to. I know an external is always the way to go but do you have a recommendation for a good indoor passive or powered unit?
Yes an outside antenna is the best, but I'd suggest you try an ordinary rabbit ears and see how it works. An indoor FM antenna can be made with a few feet of flat twin lead antenna wire, but the up side to rabbit ears is your ability to move it around if a particular station needs some fine adjusting.
This is good to know! I'm planning on putting up a dual antenna setup , so this will really help, thanks! Also, your video quality is GREAT! Holy cow! What camera are you using for the video?
In this video I used my google pixel 3 at 1080p resolution. It does an impressive job for an older phone.
What purpose does a DC pass-though serve in cabling?
If you need to use an amplifier that's mounted at the antenna, then you use the coax to pass the DC voltage up the coax itself so you don't need extra cables for the power.
The coax outer is used as ground/0V and the centre conductor carries the positive DC voltage.
Because it's possible to design splitters/combiners with capacitors inline with the signal path, which would stop the DC power on the centre conductor of tyhe coax in that leg/port, then you need to make sure you have DC passthrough and have it going on the right leg/port towards an amplifier.
Amplifiers mounted on the antenna mast close to the antenna are much more effective than amplifiers further down the coax or at the back or the TV set (or in the house). That''s because there's always some loss in the coax cable and this loss directly adds to the system noise factor, so by eliminating that avoidable loss (say, 8dB loss) with a masthead amplifier you amplify only the signal, not the signal PLUS 8dB of noise too.
Satellite systems also use this power method, the power for the LNB is passed up the centre of the coax for the same reasons. In the case of satellite LNBs they also downconvert the signal to a liower frequency range because otherwise normal coax wouldn't be able to deliver much signal (coax loss rises with frequency)
Oh forgot to add - the satellite DC pass diplexers use capacitors that are usually too low in value to pass TV signals especially into the low VHF region of the spectrum. The DC for these is added in near the LNB/antenna port. Terrestrial TV combiners/splitters usually use inductors and no capacitors on the DC pass side and they are designed for mainly 50-800Mhz kinda region of the spectrum.
The satellite ones are mainly desuigned for 500-2500 region of the spectrum, so need to use different techniques (striplines and small capacitors are common in these, with seperate DC bypass)
@@gordslater Ahh, of course, I forgot about dishes I've never been a sat enthusiast myself. I keep on telling myself to experiment with PoE (power over ethernet) one of these days. Cheers.
The DC pass through is needed where you are passing a voltage through the coax along with the TV signal for your antenna preamp or your LNB on a satellite. Conventional splitters often have voltage isolation between their inputs and outputs.
@@GrantsPassTVRepair I suppose it's basically exactly the same as being able to send your network/internet around the home through the power cables using powerline adapters. I'm not technical enough to get my head around how power and data signals can co-exist and what that involves with noise etc etc, I'll just file it under magic until I am.
I tend to stay away from splitters altogether. I have 2 tv's and 2 antennas.
Sometimes it makes more sense to use two antennas, and I've done the same, but when the signals are strong, I've rarely have problems using one antenna and a quality splitter.
from my own experience i have learned that using too many splitters, cause attenuation in every split so the last TV would get an signal of perhaps less of 20% and the tuner error correction getting overloaded
I've noticed the same problem. Sometimes I'm forced to use distribution amplifiers.
So, I have a house with existing cable (originally wired for satellite dish running through the walls ... So I re-purposed this existing cable for OTA antenna reception...
On the outside, I connect my antenna , and inside the house , connect that TV RG6 cable to my TV.. works fine... but then I add external TV amplifier unit near the antenna, and hook up the power injector near the TV and lost most of my channels.. could this be due to a diplexer inline somewhere in the walls? Or would a regular splitter also cause this problem?
You may have a bad amp. Did you unscrew the RG6 from you antenna preamp next to your TV antenna, and maks sure there was voltage at this point?
@@GrantsPassTVRepair No, I didn't check voltage yet at the pre-amp next to antenna... what should its DC voltage be there for a typical pre-amp?
could this coax/dc system with dc pass -thru splitters be used as alternative wiring to operate a home cctv camera?
or are the signals from an antenna and a camera completely different and not compatible to travel back thru the dc splitter?
Cameras are not my field or expertise, but I can't see there being any problem passing a camera signal through the DC Pass side of a splitter or diplexer. The splitters have a specific range of frequencies they are ideal for passing, but since you are talking about a closed circuit camera rather than wireless camera that use high frequency radio waves there should not be a problem that I'm aware of.
@@GrantsPassTVRepair thanks,, maybe i will try a test. all the wires on my system have gotten old and lost signal,, plus, a person could mount a camera in a location with no ac power available for the power supply , like up in a tree , or in a mail box.
Dave, you doing much work in winter? Roofs can be slippery.
Yes thanks for the warning. I'm still doing TV antennas, and I have an antenna job lined up for today, but if the roof is frozen I plan on holding off until it warms.
@@GrantsPassTVRepair ...Dave, you should really consider investing in a fall harness with a roof anchor point bracket. Roof pitches can be deceptive.
@@mwngw Na, I just keep off the roof if it's covered with frost.
This might be a dumb question, but what is the diplexer used for? Like what situation would someone use a diplexer, over a typical splitter?
From what I understand, the diplexer is designed to allow two signals to be broadcast through one coax line, with out interfering with each other, and the DC pass through side of the diplexer allows voltage to from the satellite receiver to be sent to the LNB on the satellite dish,
Ooh excellent question. I have a rig with separate 2m and 70cm band outputs both fed into a duplexer. That allows bidirectional signal flow from each transceiver to a dual band antenna while separating each radio from the other.
A diplexer is used unidirectionally (in receiving) to combine each receiver in the feedhorn to a common down wire. I’m guessing they downconvert both received polarizations to two separate lower bands then combine them, and the receiver sorts it out at the TV.
So the diplexer carries power up, and uses a high pass or passband filter to block interference from strong local signals. Hey, it got me thinking :)