: Splitters, Attenuators, Filters, Diplexers, Other Signal Gear
2007-01-23, 01:33 PM
The only other option I can think of is to put multi-channel notch filters on both antenna downleads before they are joined. Tin Lee in Toronto has them, and I believe they make a unit that will notch-out 7 channels at a time. With these you could prevent one antenna's Channel X from touching the other antenna's Channel X signal, and so on. This would hopefully allow the single downlead solution and cure the recording problems too.
2007-01-23, 02:53 PM
One thing I have wondered is if the network of filters is set up so that all channels are provided by only one antenna, do you need to use signal combiner or can you just wire the two leads together in parallel? In my mind the filters should prevent any impedance reduction issues by having them in parallel, but I might be overlooking some other issues.
2007-01-23, 09:32 PM
Thanks for the ideas. I think I would try to avoid the fancy filter setup for now. First I will try adjusting the antenna's direction, lead lengths, and relative positions. If that doesn't work I will try fishing another feed from the attic.
I will let you know how things turn out, but it will probably be a while before I have time to try all these things.
2007-03-15, 12:07 PM
I have found in this thread ideas on how to split and combine Satellite and OTA signals into a single coax running 'thru the wall'. But I'd like to add a twist. Can I run mutliple satellite receivers doing the same thing? Would I be able to use two diplexers at the 'bottom' of the run, ensuring that the DC voltage that needs to be passed through from the receiver to the LNB gets through the diplexer from either receiver? What would happen if both receivers are powered up and sending the DC voltage up the coax? Would the voltage stay the same an amperage double, or would the voltage double and amperage stay the same? What effect would it have on the LNB? Or is it my only hope to connect a single receiver feed from the dish to an OTA feed using diplexers?
2007-03-15, 12:11 PM
Another question for the group.
I understand that a basic splitter will also work as a combiner if used backwards. Are there some kind of diodes or other electronics built into a splitter that when used backwards as a combiner the signal from output 1 will not go out through output 2 - ie. is there come kind of 'check valve' on each output to only allow one-way usage? I've got a splitter inside my wall (the reason I ask the question - I don't want to open up the wall to access the cable to upstairs) that takes the cable signal and splits it going upstairs and downstairs. But if I disconnect the cable outside and push some OTA RF into the 'downstairs' output of the splitter/combiner will it go through the 'upstairs' output 2 through its coax? Is it like a garden hose wye in that the water will flow through the path of least resistance if all 'holes' are open?
2007-03-15, 01:10 PM
Are there some kind of diodes or other electronics built into a splitter that when used backwards as a combiner the signal from output 1 will not go out through output 2
When using a splitter as a combiner (or any passive broadband combiner for that matter), about a quarter of the signal will be sent out the other input (and a quarter gets reflected back on the same input). That is why you will get less than half the power on the output. See Merging feedlines (http://www.hdtvprimer.com/ANTENNAS/merging.html) for a technical explanation of exactly what happens.
2007-05-02, 01:41 PM
I had experienced some serious (and inconvenient) reduction in signal strength across the entire UHF bandwidth the last several days (see post #207 in the DXing, Tropospheric Skip, Weird Weather, Abnormal Reception (http://www.digitalhome.ca/forum/showthread.php?t=26789&page=14) thread for more info).
The fact that it coincided with me unconnecting and reconnecting a couple of cables suggested it could be a connection issue and not just a weather issue, and that is where I started. As I went through my wiring last night, I was finding no strays at the F-connectors.
Then I decided to check the conductivity of a couple of adapters in the line. Of course a continous interupted feed is prefered, but in my case that was not possible - I'm reusing cable that was in place before the basement walls were closed up. Bypassing any connection adapters is easier that checking the conductivity of the connection adapter. Just touch the wire tips of the two F-connectors together while touching the outside grounds together (with your tuner & tv on with volume up), and if you get a signal you know instantly.
Well, what do you know. I had an older connection adapter at fault. Probably corroded on the inside??
I guess with me jiggling the cables, I had somehow affected the connection adapter's ability to pass a strong signal. Replaced the connection adapter with a new gold-clad one which for some reason I had lying around - it was still in the packaging. Almost perfect reception again - just MyTV (49.1) and SunTV (66.1) wouldn't lock-up
So, I guess I'll keep this old connection adapter around in case I ever need an emergency antennuator ;) !!!
I did some search to find notch filter:
Here's my finding:
5891 UHF Trap http://www.microwavefilter.com/pdffiles/pg33.pdf
Dual UHF (Tunable)
Winegard UT-2700 http://winegard.com/offair/traps.htm
VHF (Tunable)(Electronic Kit)
VHF and UHF (Tunable - for CATV/OTA professional head ends)
and of course Tin Lee
2007-06-26, 01:46 PM
This is my first post, please excuse my ignorance. I did read a lot of previous emails (thanks to all of you), but I still need some advice.
I presently have two RG6 cables connecting the two BEV LNB outputs to two outlets in the house. I plan to install a Multistar elliptical dish (30"x33") for true FTA with 2-3 satellites, as well as a CM4228 antenna. I plan to conect FTA, BEV and antenna signals to separate TV inputs.
1) My first question is how to send all three signals to both outlets using only the two RG6 cables already installed (minimum effort). I know how to combine/extract one satellite signal and one antenna signal using a diplexer. The FTA receiver can choose the LNB via DiseqC, but I would prefer not to split one sattelite signal between the FTA and BEV receivers. Any recommendations are welcome.
2) I also would like to know if a cheap 33" dish would do just as good as the Multistar elliptical dish (30"x33") for sattelites Galaxy 25 – 97 W, AMC 4 – 101 W and Galaxy 10R (KU) at 123w. I'm located in Whitby, Ontario (40 km East of Toronto).
2007-06-27, 09:36 AM
cbanica if I understand you first a single round 33" dish would only get one satellite.
That elliptical dish 33x30" would be able to provide up to 4 satellite feeds from 91 to 123'. You would need to connect all the satellites to the DisEqc switch then take the output from the DisEqc(rec) to the input of the diplexer sat input and the antenna to the antenna input.
Then connect another at the end where your sat and astc tv tuner is.
This will work fine have doen thgis before if this is what you are asking. :)
2007-06-27, 11:41 AM
This will work fine with one FTA receiver. My question was how to separate satellite signals for both the BEV and the FTA receivers.
2007-06-27, 09:47 PM
My question was how to separate satellite signals for both the BEV and the FTA receiversI dont quite understand what you are asking but if you are asking can you separate the bell signal from the fta line that is a no.
To run two sat receiver fta or regular you should be using dual output lnbs. One side can be for fta and the other side regular receiver.
Then just connect the antenna side how I described before.
Hope this is what you are asking.
2007-06-28, 08:49 AM
Yaamon, thanks again.
Yes, the two outputs from the LNBs feed two different coax lines. The problem is that the BEV receiver cannot drive the DiseqC switch (I'll use 3 or 4 different dual LNBs, including BEV for 91W).
I guess I have to use the FTA receiver for switching between satellites and make the BEV receiver its slave somehow.
2007-06-28, 09:30 AM
That is right the bev receivers are not compatible with the DisEqc switches and you have to use a SW21 switch or a Dish/Bell type powered switches.
You can use a SW21 to connect any two of the same format satellite with the Bev receiver from the second ports of the lnbs.
My wires is getting messy again but here is what I have in my garage.
The track from my garage door is blocking the Sw and DiSEqc switches
2007-07-18, 12:58 AM
I've got an FTA system, rogers cable and a CM4228 for OTA. Is there any way I can bring all 3 cables to a central location in my basement, use some sort of multi switch so the signals can be sent to every TV in the house able to receive the signals.
The TV in my bedroom has an ATSC tuner as well as the main TV in the Family room. I don't care for satellite in the bedroom as I don't have a second receiver. All I care for is Rogers cable in all rooms, OTA on the bedroom TV and everything on the main TV in the family room.
I have RG6 running to all the rooms.
2007-07-18, 10:07 AM
mrmetro with a pair of diplexers you can combine cable or ota with satellite.
So basically for your bedroom one cable cannot carry cable and ota. The reason is that they use the same frequency.
Cable and ota basically uses 50-852mhz and satellite uses 950-2150mhz. Diplexers split the frequency band.
So Iam afraid for your bedroom you would need to run another cbale up there.
2007-08-15, 09:30 AM
And you have raised an interesting point: tweaking is good! Nevertheless, I think what you're seeing is that a balun represents one of those things you'd do to get all the signal that you can after you've done all the big stuff. Don't be discouraged or dissappointed if we aren't giving you the response you expected. Let us know how your work progresses. :)
I'm interested in this too: what is the "best balun" ?
2007-09-14, 10:54 PM
Maybe someone can help. I am attempting to combine a Channelmaster 4221 and 4228. Also would like to use a diplexer to send a signal to my bedroom with out having to run a new wire. Also, have a channel master preamp but unsure where to add it inline. Any help would be appreciated.
2007-09-15, 02:12 AM
maddawg, as far as joining 2 antennas, you might be in for some real aiming quirks. I have a CM4228 and an old Delhi 4-bay bowtie reflector up on my roof facing almost 180 degrees apart, and I run identical lengths of coax from their baluns to a simple low-loss splitter that I hooked up in reverse so that the downlead actually emerges from the coupling labeled "input". I have tweaked and tweaked those antennas just to see what would happen and finally arrived at a suitable combination of aiming points. Other posters in the OTA Forum have similar tales of dual antennas interacting weirdly with eachother.would like to use a diplexer to send a signal to my bedroom with out having to run a new wire. Also, have a channel master preamp but unsure where to add it inline.For my diplexer/preamp recommendation, with diagram, see Posts #72 through 80 in this thread.
2007-09-16, 03:25 PM
So had it installed and this is the result: http://www.digitalhome.ca/forum/showpost.php?p=602850&postcount=219