Antennacraft ST2 cable connection

[cmartellw]

Ok guys. I just spent over three hours reading past posts trying to find this answer without no success. So therefore I have no other option other than ask it. I am sorry if this has been discussed prior, but I don`t have days to keep reading posts.
I have a Antennacraft ST2. Instead of using the supplied 75 ohm cable that came with the antenna, could it be set up using LMR400 50 ohm cable instead? I have a 50` run extra from a misorder on Amazon. I`m pretty sure that I can. The only question that really needs answering is how do I, or can it be possible to connect a PL259 adaptor or a N adaptor to the twin lead wingnuts on the antenna? Can I still use the 300 to 75 Ohm Balun that came with it(are there different types?)and use an UHF-Female to SMA-Male Adapter? How does the 50 and 75 ohms convert correctly for the new 50 ohm cable? Am I thinking more into this than needs to be? I only ask because once this antenna is mounted, I don`t want to bring it down again for any reason.

 

[wmbio]

That is exactly the set up I have, the impedance on receive is minimal using LMR 400 cable, I had to use an N female to F male adapter at the matching transformer and an N female to BNC male at the scanner. Use the matching transformer as designed, weatherproof the adapter connector at the base of the matching transformer and you should be good to go with what ever adapters you need to use with your cable

Very happy with the results!

Enjoy
Wmbio

 

[n5ims]

You'll still need the balun to at least convert from the 300 ohm balanced antenna connector to your lower impedence unbalanced coax (balun stands for balanced to unbalanced converter). The 50 or 75 ohm impedence mismatch will be minimal while using an unbalanced feedline connecting to a balanced antenna can cause the feedline to pick up all kinds of noise.

What connector is currently on the LMR-400 since you're pretty much stuck with using an F connector on the antenna end either directly or through adapter(s). They do make UHF to F adapters so if you have a PL-259 you can get a UHF Female to F Male and be good on that end. Be sure and secure the coax well at the antenna end or the weight will rip the balun off the antenna after a while.

On the scanner end it sounds like you need an SMA connector. That's pretty tough when using LMR-400 since the connector is rather easy to overstress and the coax is stiff and can easily cause stress on the connectors. You probably should use a short jumper type adapter on that end to allow the jumper to absorb all of the stress instead of your scanner's connector. This jumpter can either be premade (it's pretty easy to find an N to SMA jumper, just make sure that the ends match what you need since they come in both male or female on either side) or many providers can make them up for a few dollars.

The 50 ohm vs 75 ohm impedence issue for scanners is generally not much of an issue. In your case the issue will be will this be at the scanner end or the antenna end and the result is the same either way. For attaching a wide frequency range antenna to a wide frequency range scanner the 50 vs 75 ohm difference isn't something I'd worry about at all.

 

[cmartellw]

It sounds like there would be hardly a notice of signal loss if I were to use the PL259 to a SMA adaptor at the antenna side. I just wanted to be sure. The LMR400 has a PL259 on one end and an N connection on the other. My plans were to cut the N end off and solder on another Pl259 adaptor connected to a PL239 BNC right angle to the scanner. There are so many 300 to 75 Ohm Baluns out there. Is there a superior on to use for the 50ohm cable? What should I look for? Thanks...

 

[Techy]

Hi cmart, I used the cheapie baluns in the past on my scanner antenna and found them to be junk. Some were waterlogged, and the spade lugs rusted. I now use and found it to be the best balun, is the "Channel Master 94444" model. Very solid balun. The lead wires are pigtails and have no spade lugs to rust out. Low loss with this one over the cheapies. They are found for sale on the bay site and at channel masters web site.

 

[Quickcall]

Sounds like the setup I have. I have an F to PL259 connector from radio shack hooked up from the blaun to LMR400. Works great.

 

[cmartellw]

Thank you so much. Have an eye on two at ebay, though they go off in five days. Not many places to get them is there. They are fairly cheap at Channel Master, but they gouge you with shipping. Three dollar item and fourteen dollars for shipping. Think I might bite the bullet and buy from a Canadian store for a total of ten dollars. Thanks again.

 

[smittyj77]

I have the ST-2 Antenna, Just purchased from Radio Shack on Ebay, ran exisiting coax I had run off my TV tower that was for one of my sateliite dishes, signal is awesome and crystal clear - works great for me.

I am running a home patrol on it now, and just purchased a 396T that I want to run off the same antenna.

What is the best way to split the signal from the coax to my Home Patrol and my 396T ?

Thanks


Sent from my BlackBerry 9900 using Tapatalk

 

[n5ims]

What is the best way to split the signal from the coax to my Home Patrol and my 396T ?

Start with reading the sticky on this very topic. It has several good tips and comments on why some options are much better than others.

http://forums.radioreference.com/passive-devices/105054-using-one-antenna-multiple-scanners.html

 

[smittyj77]

Another question I hope that someone can help me with. I have a Uniden Homepatrol and a Uniden 396T i am going to run both from my ST2 Antenna. Im going to run the ST2 into a Electroline EDA2400 Four Port. Does anyone make a right angle sma to coax or a sma right angle with a coax pig tail? I would like a right angle sma to coax for the 396T and just a straight sma to coax for the home patrol

 

[K7CAR]

Why are you switching to LMR-400? I'd be very surprised if it makes any difference in receive over the stock cable you have on it and a good chance it will decrease your reception. When you get done with the add on adapters to make the 400 work you will have lost any added benefit of the better coax. Hook it up with the stock cable and see if that works for you. Money is better spent on height rather than coax when it comes to the best bang for your buck. If you don't have marginal reception stations as your goal the ST-2 will work well without a lot of $$$.

 

[cmartellw]

Why are you switching to LMR-400? I'd be very surprised if it makes any difference in receive over the stock cable you have on it and a good chance it will decrease your reception. When you get done with the add on adapters to make the 400 work you will have lost any added benefit of the better coax. Hook it up with the stock cable and see if that works for you. Money is better spent on height rather than coax when it comes to the best bang for your buck. If you don't have marginal reception stations as your goal the ST-2 will work well without a lot of $$$.

The original just worked fine with the Scantenna. Wind storm brought down both antennas and the discone cable which was Belden 9913 was nicked right in the center of the line so it had to be replaced. Put both back up using LMR for a slight upgrade in cable. As I stated in the original post I had a 50` run of LMR that was misordered so I wanted to use it because I had it, I didn`t spend any extra for it. Anyway, for those who are wandering how I accomplished my original posted question. I found an "N to a F UHFmale" adapter for the Scantenna UHFwhich I used a "Channel Master 94444" balun and a BNC right angle to the scanner for both feeds. Thanks for the input guys.

 

[ScanMaine]

Instead of using the rg6 50 ft. Can I attach 100 feet and put a bnc on it? I have my antenna up over 40 and its anohter 75 to 90 feet to my radios