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Loss in splitters

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normally, 6 to 12 dB, depending on quality of design and materails used. A connector itself (like a Female to Female coupler) adds 6 dB loss.
 
I was able to split the signal from their dipole (Antennacraft FMSS clone) three ways before the signal became noisy. Then I added a nice, quiet amp and all was well.

Of course, the signal strength that reaches your antenna might be different. YMMV
 
Manitoulin said:
normally, 6 to 12 dB, depending on quality of design and materails used. A connector itself (like a Female to Female coupler) adds 6 dB loss.
Click to expand...
:yikes: Are you kidding me?? If that's the case, then I'm down like a minimum of 36dB from antenna to input!
Tom
 
3.5 db at every output of a splitter. ie: 2 way splitter = 3.5 + 3.5 = 7 db, etc. Connections usually add approx 1.5 db loss.
 
I'm trying to pick up some fringe stations I am now getting well in mono, but stereo is noisy. Present antenna is a Godar FM1A in the attic going to my main tuner (Onkyo T-4500 w/ filter mods). Since I am mounting an outdoor antenna on the same end of the house as my bedroom, in fact, just above the window behind my bedroom receiver, I thought, why not just put a splitter and drop a line to that receiver, too?

If too much signal loss, I'll just splice in an amp before the splitter.
 
This sounds about right.

JimmyNeutron said:
3.5 db at every output of a splitter. ie: 2 way splitter = 3.5 + 3.5 = 7 db, etc. Connections usually add approx 1.5 db loss.
Click to expand...
Although I think the 1.5 db insertion loss of a coupler is a bit high.

Doing the math, assuming a two way splitter with a 100% efficiency (which isn't possible), the power would be divided equally between each leg, or a 3 db loss on each leg. Adding about .5 db for insertion loss seems more like it.

Again, I was able to do three sets of a small omnidirectional antenna before signal loss became an issue.
 
Mark you are correct about the 1.5 to .5 db. I mistyped the .5 to 1.5. Each connection (coupler, connector, etc) adds .5 db loss. A splitter is not 100% efficient, thus you lose 3 db at every tap, then add the .5 db loss for the connection and you have your 3.5 db loss at every tap. Keep in mind that the DB loss is not linear. It will vary depending on frequency and resistance. Use good cable, good connectors, and the fewest splices and you will be fine for FM. Add an amp if needed.

Jimmy
 
OK this is an off the wall idea and maybe not for everyone BUT a very nice 1/2 copper water pipe J pole antenna can be made for well under $20.00 I think I had like $12.00 total in mine including some new nuts and bolts for mounting it. If you have two recievers or tuner why not let each have their own antenna.

I have two systems operating th SHRINE in the living room operates off a 99Mhz tuned J pole antenna mounted at the high point of my roof approx 18 feet off the ground at the base of the antenna. The other system is in my office it is running off an indoor antenna I made called a Modified Cubic Quad that sits on my desk. Both systems use a Pioneer TX-9100 tuner and both will pull in all the stations I normally listen to (the J pole will pull in stuff much further out or weeker then the indoor.

I am planning on building two more J Poles that will be roof mounted one to feed my Tube system tuner which will also be in the living room. The other will be a new source for my Office tuner. This will free up the indoor Cubic Quad to be used as a test antenna. Or for the tube sytem I want to add to my office.

I also have some soft 1/4" aluminum tubing I have been thinging about making some J pole antennas out of for indoor use just sticking them in a room corner out of the way.
 
Well, I have borrowed a really tall extension ladder... the antenna goes up tomorrow. If you don't hear from me for a while, I fell off.
 
Manitoulin said:
normally, 6 to 12 dB, depending on quality of design and materails used. A connector itself (like a Female to Female coupler) adds 6 dB loss.
Click to expand...
Hmmmm......where did you get these numbers?

Normally, a splitter does just what it says. If it is a 2-way, it splits the signal by 2, or 3db per side (half of the signal goes to each of the outputs). If a 3-way, then splits it by 3, and so on. As for couplers, if it is simply a female-to-female coupler and is dropping more than about 0.3db then there is something wrong with it.

Personally, to avoid these loses, I used an F-switch. Even the cheapy ones only have about a 0.5db loss. You just have to remember to switch it between tuners, which is a simple push of the button. PE sells several different models for $10, or so.

JimmyNeutron said:
Add an amp if needed. Jimmy
Click to expand...
Keep in mind that adding a signal amp will amplify the noise as well as the wanted signal. Should only be used as a last resort. YMMV
 
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No ladders or children were harmed in the installation of this antenna! :no:

I installed the Radio Shack $25 FM antenna (really an Antennacraft FM6).

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Used the eaves mounts. My big kid (6-foot +) held the extension ladder while I drilled holes and bolted on the brackets. My very slim daughter got up on the roof and held the antenna while I tightened the brackets. Only minor eye rolling on her part.

And I didn't fall off the ladder. :D

Note that I actually remembered to buy a ground rod. I have the ground wire attached, but not yet anchored to the side of the house.

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And a "drip dip" in the cable so that water will not run along it and drip into the attic, but rather off the bottom of the dip.

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About the ground wire. If anyone really thinks that in case of a lightning strike, that the lightning bolt will follow that wire, and carry 8 gazillion megawatts, you need to study up on lightning. But what the wire will do is lessen the chance of a strike. That is the way lightning rods work. They drain off the charge in the earth into the air, lowering the potential. This is what happens when you see "St. Elmo's Fire" or a glow around ships masts or the ends of antennas during a storm.

Oh well, that's all that can really be done. If we get a hit I'll just buy new gear.

No report on performance yet. By the time we got it up it was too hot in the attic to make the connection.

Right now I have the antenna aimed halfway between two distant cities that are about 40 degrees apart. The antenna should pick up both pretty well. :scratch2:

My plan is to set the tuner to a station in one of those distant cities, use my cell phone to talk to my son, aim the antenna for best signal. Then have him switch to another station in the other city, find the best direction for that station, then aim halfway between and see if both come in with acceptable levels. If so, then I won't need a rotor. :thmbsp:

Tomorrow, very early, skinny daughter goes up in the attic to disconnect the Godar and connect the outdoor antenna.

Then :banana:
 

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c''mon, Jim. We all know how this story is gonna end, don't we?

I'll give ya a hint. It starts with "R" and ends with "otater".

You're no treally gonna be totally happy without it and you know it. :yes:

Heck, with a yagi and stations all ove the map, I sure as heck wouldn't be.

That's why I bit the bullet and went with an onmi in the first place. The temptation is much, much less.

Good luck, and you owe your daughter big time.
 
Good luck, and you owe your daughter big time.

Funny you should mention this... she keeps reminding me.

As far as a rotator, I live on the coast, and everything I want to listen to is in the same general direction. So, I might get by without it.

But there is still that nice jazz station I used to pick up 200 miles to the west with a Channelmaster TV antenna...

UPDATE!!!

Daughter got up in the attic this morning and disconnected the Godar and connected to the new outdoor antenna.

I am getting about 3x more stations, and what were marginal stations (50%, good mono) before are now 70%-80% signal strength clean stereo. There are many stations pegging the meter now.

:banana:

I have the antenna aimed, as above, about halfway between two distant (60-65 miles) major cities about 40 degrees apart, and I am getting all of the stations I wanted from both, nice and clean. And more!

c''mon, Jim. We all know how this story is gonna end, don't we?

I'll give ya a hint. It starts with "R" and ends with "otater".

NOPE! No rotator needed at all!

Dang! I just realized, I have to rework all of my memory settings. I don't think 40 presets will be enough! :scratch2:

Well, I won't worry about putting a splitter in the line now. :D

UPDATE #2

I ran out of presets. :D
 
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please post a list of all stuff needed

Paul,

I am convinced to go pick up the FM6 antenna, but I need to know what else I need that isn't included in the box. My receiver has a coax connection for the FM antenna. Can you give me the ultimate soup to nuts list so I don't have to make multiple trips to the store to pick up that extra doomahickie I didn't think about until I was in the attic. By the way, somewhat related question, do you have any other contact information for the AM loop guy?

Jeff
 
So I am assuming you tried your TV cable and Cox did not have FM in your area? If your TV cable is near your receiver that would have been the easiest thing to do, a splitter and another cable coming to your receiver or tuner.

Only the antenna is in the box. 15-2163 "High-gain directional FM-stereo antenna" It does have a U-bolt and nuts to attach to a mast (pole). BTW, it is 70" long and 66" wide.

RS has a rafter mount to hang it in the attic. 15-882 "Universal mast attic mount" This is discontinued I think, but the store may still have one in stock. If not, get bracket 15-888 and 5 ft mast 15-862. You may have to shorten the mast with a hacksaw. If they don't have 15-888, you might be able to use 15-883 screwed to your rafters and ceiling joists, one on top, one on bottom of the 5' mast with the antenna in the middle.

You will need some 300 ohm twinlead. That'll work fine for you. That's all you will need. Since you are using this for indoors only you can get the cheap stuff. 40 ft roll 15-0004. You can use the same for your AM antenna.

That's everything you need.
 
OK back to the question of a splitter.

Instead of a splitter why not use a switch? I see really nice looking Heathkit Coax switches on ebay all the time used by HAM's I assume to change antennas.

I have been thinking about getting one. But I'm still planning on a small J Pole forest on my roof. Right now up to needing a total of 4. I like the omidirectional nature of a J Pole not to mention the minimalistic cosmetics.

I have a section of facia board that is almost at the peak of my 2 story house but is completely blocked from view of the street or anywhere on my lot. Sure the neighbors can see it from their deck but hey they sit on the deck and drink beer so what will they care if I run up 3 more nice looking J Poles. Think I will!
 
You can purchase F-connector switches for less than $10 from PE. Just click on their logo below and do a search. I've had good succes using them for the past few years.
 
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