RG-11 Cable Assemblies

[LIScanner101]

I’m looking for a source of pre-made RG-11 coax cables. Specifically:

N male to F male, anywhere between 10’ to 40’
N male to BNC male, RG-11, anywhere between 10’ and 20’.

Pasternack is the only place that I can find but they are PRICEY.

Thanks for any help!!

 

[prcguy]

Generally speaking, any N connector made for RG-11 will be 75 ohm and have a smaller diameter center pin that is not compatible with a 50 ohm type N connector.
prcguy

 

[mmckenna]

Save yourself a headache and just get some pre-made Times Microwave LMR400 instead. You'll have a much easier time finding custom/premade cables with the connectors you want.

 

[mpddigital]

We stock Times/Amphenol RG-11 that is good stuff. In the past we carried Times LMR-400-75 Ohm but the long term demand wasn't there.

While RG-11 is a solid alternative for scanner use and we make up many assemblies by the foot for this use, we normally do it with UHF connectors which are not impedance matched and work well or use 75 Ohm BNC connectors. We can obtain other connectors but in most cases it is not cost effective. If you can explain specific applications for the coax I might have other ideas. If cost is an issue there are less expensive (but not necessarily better) options to LMR-400 and I can suggest several depending on your length of run and frequencies.

 

[LIScanner101]

Thanks. I'm looking for some extension cables between antennas and scanners. The main concern I have is the flexibility-to-loss ratio:

RG-58/U - very flexible, very lossy
LMR-240 - thin, but heavy solid conductor AND lossier than thicker cables.
RG-6/U - thin, flexible, but lossier than RG-11
LMR-400 - VERY low loss but very thick and too rigid

RG-11 seems just about right - not too thick, lower loss than RG-6/U but much more flexible than LMR-400.

Aren't UHF connectors lossy above 500MHz?

 

[GTR8000]

RG-11 seems just about right - not too thick, lower loss than RG-6/U but much more flexible than LMR-400.

That's a bit of a stretch. While 50 ohm coax does have a thicker center conductor than 75 ohm coax (LMR-400 vs RG11), the diameter of the cable is roughly the same, and they are both pretty bulky and not particularly well suited to connect directly to a scanner (unless they are base/mobile units that are solidly mounted and there is strain relief on the coax so the BNC doesn't take the brunt of it).

Don't take offense to this, but it sounds like what you're looking to do is overkill. You're talking about fractions of percentages of dB loss here, especially for very short runs of coax. The adapters will kill you more than anything else.

Do yourself a favor and stick with 50 ohm LMR-400 with quality connectors. If you haven't yet purchased antennas, stick to ones that feature N connectors rather than UHF (PL259). UHF connectors were really never intended to handle frequencies above 300 MHz. If you are as concerned with preventing as much loss as you seem to be (referencing this thread and your "TNC vs BNC" thread), then you want to avoid UHF and stick with N. Most quality antennas either come standard with N, or offer it as an option.

As far as the jumpers, here's what you do: Purchase the LMR-400 with N-male connectors at both ends. Then, get a short (2 foot is fine) LMR-240 N-female to BNC-male jumper and put it between the LMR-400 and the scanner.

Problem solved.

 

[LIScanner101]

Chauffeur6,

Thank you for the good info. You had mentioned that one should try to stick with antennas that have N connectors which are almost universally 50 ohm. I have a case where I have a Scantenna and a vintage Monitenna. Both are dipoles, and both come with baluns with female F jack. They also come with RG-6/U with F connectors on both ends. RG-6/U is of course decent scanner coax, but not as good as RG-11. Either way, what should one do here? Put an F-to-BNC adapter at the scanner of the coax? What if you have a really long run? I would imagine RG-11 would be the better choice here, but even if you do you still have to connect the scanner to the antenna. F's on both ends and use the same adapter I mentioned? I think if you wanted to reduce coax loss even more you could go with LMR-400, but you still have the same connector issue. In this case, I guess you could get an F made for LMR-400 on the antenna end but those are expensive.

 

[GTR8000]

If both of your existing antennas have F-female jacks, then yes, RG11 would be the better choice.

I would probably go with RG11 with F-male connectors at both ends (use only high quality Thomas & Betts Snap-n-Seal compression connectors), then a short pigtail of RG6 with an F-male and BNC-male. You'll have to use a good quality F-female to F-female barrel connector to mate the two cables (they are rated up to 3 GHz these days).

https://www.tessco.com/products/displayProductInfo.do?sku=468462

https://www.tessco.com/products/displayProductInfo.do?sku=387002

https://www.tessco.com/products/displayProductInfo.do?sku=78990

https://www.tessco.com/products/displayProductInfo.do?sku=42214

You're really limited to what you can do because of those F jacks on the antennas. The good thing is that RG11 and RG6 and F connectors are cheap as hell compared to 50 ohm stuff, and the loss is comparable.

 

[LIScanner101]

Thanks again Chauffer6. Is there any reason why it wouldn't be better to terminate the main cable with an F female (crimp or compression) instead of using a male and then having to add another adapter (i.e., the F female-female)?

And can you tell me a little about these compression connectors? All my life I've always crimped. Are compression connectors "better" in some way?

 

[GTR8000]

I seriously doubt you're going to find F-female connectors for RG11 or RG6. Even if you did, it would be no different than using an F-female to F-female adapter. Either way the center conductor of each cable is going into a sleeve to mate the two cables together.

Compression F connectors provide a better environmental seal than crimp connectors, and are just as strong, maybe even moreso. They're built better than crimp connectors, you can tell just by looking at them and feeling the weight of them, very solid construction. They're also really easy to put on, requiring a 1/4 strip of the outer jacket with braiding folded back, and a 1/4 strip of the dielectric to expose the center conductor. You will need the right compression tool to install them, though. I believe you can get a tool that will do both RG11 and RG6.

 

[LIScanner101]

I seriously doubt you're going to find F-female connectors for RG11 or RG6. Even if you did, it would be no different than using an F-female to F-female adapter. Either way the center conductor of each cable is going into a sleeve to mate the two cables together.

I actually browsed around and found an F female with a crimp/solder-on pin. This means that the center conductor of at least one side of the cable will not just be inserted into another female pin and just rely on spring-loaded contact, but will be a much stronger/solid connection. Now, whether or not they make these for RG-11 is another story but you got me thinking...!

http://www.pasternack.com/images/ProductPDF/PE44324.pdf

Compression F connectors provide a better environmental seal than crimp connectors, and are just as strong, maybe even moreso. They're built better than crimp connectors, you can tell just by looking at them and feeling the weight of them, very solid construction. They're also really easy to put on, requiring a 1/4 strip of the outer jacket with braiding folded back, and a 1/4 strip of the dielectric to expose the center conductor. You will need the right compression tool to install them, though. I believe you can get a tool that will do both RG11 and RG6.

I'll have to look into these, sounds good. In my case the antennas are most likely going to be attic-mounted so environmental concerns are mitigated but it sounds like there are numerous other advantages.

Thanks again for all the excellent info.

 

[mmckenna]

Some very good advice there.

Here is what I'd add, though:

Antennas do not last forever. Neither does coaxial cable. Since your antennas are old, I wouldn't design your new cable plant around old antennas. Look to the future and the idea that some day you'll likely want to replace those antennas. You'll be wanting N connectors, but you'll be stuck with using adapters on F connectors.

Instead of doing that, go with the LMR-400 and use adapters to connect to your old antennas. That way when the time comes to upgrade your antennas, just pull the adapters off and connect.

Meantime, you could look at your current antennas and see if you can replace the existing antenna connectors with "N" connectors. Likely the old connectors are getting weathered pretty bad.

 

[GTR8000]

I completely agree with mmckenna.

My post assumes you are set on keeping those two old antennas with no plans to replace either of them. If that is true, then you may as well stick with 75 ohm and F connectors the whole way through, rather than degrade your signal even further by using adapters. Let's be honest, the very fact that those antennas have baluns and F connectors is probably the weakest link in the chain at this point.

If you think you'll replace those antennas at any point, then mmckenna is spot on. Go back to my original LMR-400/LMR-240 suggestion and keep it 50 ohm with standard RF connectors, using an adapter to get from N to F at the antenna end of things.

I actually browsed around and found an F female with a crimp/solder-on pin. This means that the center conductor of at least one side of the cable will not just be inserted into another female pin and just rely on spring-loaded contact, but will be a much stronger/solid connection. Now, whether or not they make these for RG-11 is another story but you got me thinking...!

Again, not to be a jerk about it, but you're really nitpicking here. If we were talking about high quality components throughout, I would be inclined to agree with you. The fact is, you're talking about old antennas with baluns and F connectors (as I already pointed out, the weakest link in the chain and the most lossy part of the entire system), going into 75 ohm coax with F connectors, to a consumer grade scanner. You are not going to notice one bit of difference between an F-female connector versus an F-female to F-female adapter.

If you're truly serious about designing an antenna system that will minimize as much loss as possible, you should start with antennas that have N connectors, and get them out of the attic. You've got more loss from those two factors than you would overcome with the best coax and connectors.

 

[LIScanner101]

Sorry guys. I tend to go WAAAY overboard on some things. I do realize that my attic mount method is bound to set me back loss-wise but I try to control what I can control. For example, I can't control the fact that I most likely will be unable to install an exterior antenna, but I have control over my choice of connectors and coax. That's all I am trying to do. As far as the antennas go I don't plan on replacing these antennas because the Monitenna is an amazing antenna and the Scantenna is almost as good. Maybe someday I shoukd get a 50 ohm antenna, but not until my current ones are long buried. Thanks agsin for all the advice.

 

[mpddigital]

If you decide to go with Tessco or Talley for jumpers and they are asking list price give Kim a call or shoot an email. She gets a pretty good discount off list prices and will pass it on.

 

[LIScanner101]

If you decide to go with Tessco or Talley for jumpers and they are asking list price give Kim a call or shoot an email. She gets a pretty good discount off list prices and will pass it on.

Thanks for the tip!

 

[rylvir]

I recently purchased some LMR-400 with BNC-male and N-male Connectors,an N to F adapter (50ohm/waterproof) along with a new balun to try with my ST-2 Scantenna. Honestly, I will not be surprised if there is no noticeable difference. I have read enough posts here on the forums and reviewed the times microwave calculator to see what kind of loss I might gain back. So if that doesn't work out so well, at least I have proper LMR400 to feed a Yagi antenna or whatever else - I'll let you know the results -

 

[LIScanner101]

I recently purchased some LMR-400 with BNC-male and N-male Connectors,an N to F adapter (50ohm/waterproof) along with a new balun to try with my ST-2 Scantenna. Honestly I won't be surprised if there is no noticeable difference, I've read enough posts here on the forums and reviewed the times microwave calculator. So if that doesn't work out so well, at least I have proper LMR400 to feed a Yagi antenna or whatever else - I'll let you know how it works out.

Interesting, why are you changing your day balun? I have no idea of what the quality level is of the baluns that originally came with my Scantenna and Monitenna. Are there "professional" 300 ohm to 75 ohm baluns out there?

 

[rylvir]

I just wanted to start with everything brand new, and improve the waterproofing. Other than a recomendation found on the forums here I didn't find much information on quality baluns- I went with a Channel Master 94444, but the ones I received have insulated eyelit connectors instead of the pigtails shown on this post and the web.

http://forums.radioreference.com/sc...nacraft-st2-cable-connection.html#post1826445

 

[LIScanner101]

I just wanted to start with everything brand new, and improve the waterproofing. Other than a recomendation found on the forums here I didn't find much information on quality baluns- I went with a Channel Master 94444, but the ones I received have insulated eyelit connectors instead of the pigtails shown on this post and the web.

http://forums.radioreference.com/sc...nacraft-st2-cable-connection.html#post1826445

Gotcha, thanks. I am going to pick up a couple of those CM 94444's myself, can't hurt.