whats the difference??

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hawkeye32

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just wondering what the big or if any difference between LDF1-50 Heliax and LMR-400 coax?? Also whats your opion on both of these?? Ijust purchased 75 feet of the LDF1 and it will be connecting to a scantenna,and into BC898t, mostly going to be monitroing Mil/Air and trunk system any thoughts or suggestions would be cool...Thanks
 

VA3QRM

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coax comparison / try this

http://www.timesmicrowave.com/cgi-bin/calculate.pl
mil air 200 mhz (?)
trunked 860 mhz
Both look good re:attenuation compared to say RG-58, get the proper connectors, no adapters and you'll be in business.
Thinking of upgrading my coax as well for my ham / scanner antenna.
Best of luck with that.
 
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prcguy

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They both have nearly the same loss and the tiny heliax is probably easier to work with. PL-259s will fit the LDF1-50 but any other connector is going to get expensive. Connectors for LMR400 are cheap.
prcguy
 

hawkeye32

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ok its just a plain pl-259 and a bnc connector for the scanner but it is suppose to come with both of those either already on or i have to put all in all i think it was 110 or 105 for 75 feet from a guy on this site
 

hawkeye32

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also just another quick question am i going to be needing a amp with 75 feet worth or should i be fine??
 

VA3QRM

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hawkeye32 said:
also just another quick question am i going to be needing a amp with 75 feet worth or should i be fine??
I am sure with the good coax and getting that antenna up as high as you can; above the roof and trees if possible, you'll be fine.
 

af5rn

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hawkeye32 said:
also just another quick question am i going to be needing a amp with 75 feet worth or should i be fine??
How are we supposed to answer this, not having the slightest clue how far you are from the systems you are monitoring? Very, very few applications actually end up requiring a pre-amp. Unless you are trying to listen to VERY distant 800 systems, it's just extremely rare that they are needed. Usually, anything far enough away to require that is something you're not interested in hearing anyhow. You'd be better off just adding height to your antenna. Preamps do NOT make up for inadequate antenna height.
 

VA3QRM

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what trunked system do you want to listen to?

hawkeye32 said:
just wondering what the big or if any difference between LDF1-50 Heliax and LMR-400 coax?? Also whats your opion on both of these?? Ijust purchased 75 feet of the LDF1 and it will be connecting to a scantenna,and into BC898t, mostly going to be monitroing Mil/Air and trunk system any thoughts or suggestions would be cool...Thanks
Just curious. I am in Windsor as well and think with better coax and some height you should be able to hear the Michigan system and most southeastern Michigan 800 mhz stuff no problem. Maybe the Ohio MARCS and Lucas County on a good day. As AF5RN says be careful with pre amps, when you the local stuff comes up you can "roast" ( de-sensitize ) the receive on your scanner if the pre-amp is on.
 

prcguy

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Is that $110 or $105 that you paid for 75ft? Since the loss specs for LDF1-50 and LMR400 are about the same and LMR400 is well under 50c/ft, what are you getting for the extra money? Heliax has its benefits but for the type of service you are using it for I think LMR400 is a better choice. I also have a few 75ft runs of LDF1-50 on my tower but it was surplus and almost free.
prcguy
hawkeye32 said:
ok its just a plain pl-259 and a bnc connector for the scanner but it is suppose to come with both of those either already on or i have to put all in all i think it was 110 or 105 for 75 feet from a guy on this site
 

Lowa2

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I do not want to start a pissing match here..but here is my reason to use LDF.

In Air Navigation system installations, we use LMR400 to interconncect transmitter racks, monitor racks, power dividers ect....on the INSIDE of buildings. As soon as we cross over to outside applications, heliax is the cable of choice.

I know the guy isn't providing accurate info to aircraft, but for mechanical strength, ease of installing connectors, and smaller OD cable, durability, I'd rather use heliax. But thats just me. We just have more problems with LMR than LDF (Birds eating the cable, LMR seems "tastier" than heliax LOL)

For backup VHF and UHF systems, we use LMR400FR, but for all main VHF and UHF comm systems, we use LDF4-50A up the tower with LMR400 on the inside of the buildings between the radio and the heliax.

On a positive note for the LMR, we use on almost all our radar work cables, and LF/MF applications, and it seems to work out pretty good. I especially like LMR200, WAY WAY better than RG58 or RG223.

Both cables are great choices, and I know everyone on here loves LMR400, but everyone has their "preference" i guess. The only real "annyoance" i found with LMR is that the center pin on the "N" connectors is very thin metal, and breaks easily. But other than that, great stuff.
 

n8emr

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And for the average Joe wanting to listen to local systems, RG6 would be more than enough coax.
 

prcguy

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I use lots of LDF1-50 at work in the 12 to 14GHz range where LMR400 and its connectors are not usable but at retail prices or even surplus prices, LDF1-50 has nothing to offer the ham or scanner user for the extra $$ spent. If you have money to blow then move up to LDF4-50 where you get down to 2dB loss/100ft at 800MHz.
prcguy
Lowa2 said:
I do not want to start a pissing match here..but here is my reason to use LDF.

In Air Navigation system installations, we use LMR400 to interconncect transmitter racks, monitor racks, power dividers ect....on the INSIDE of buildings. As soon as we cross over to outside applications, heliax is the cable of choice.

I know the guy isn't providing accurate info to aircraft, but for mechanical strength, ease of installing connectors, and smaller OD cable, durability, I'd rather use heliax. But thats just me. We just have more problems with LMR than LDF (Birds eating the cable, LMR seems "tastier" than heliax LOL)

For backup VHF and UHF systems, we use LMR400FR, but for all main VHF and UHF comm systems, we use LDF4-50A up the tower with LMR400 on the inside of the buildings between the radio and the heliax.

On a positive note for the LMR, we use on almost all our radar work cables, and LF/MF applications, and it seems to work out pretty good. I especially like LMR200, WAY WAY better than RG58 or RG223.

Both cables are great choices, and I know everyone on here loves LMR400, but everyone has their "preference" i guess. The only real "annyoance" i found with LMR is that the center pin on the "N" connectors is very thin metal, and breaks easily. But other than that, great stuff.
 

Lowa2

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prcguy said:
I use lots of LDF1-50 at work in the 12 to 14GHz range where LMR400 and its connectors are not usable but at retail prices or even surplus prices, LDF1-50 has nothing to offer the ham or scanner user for the extra $$ spent. If you have money to blow then move up to LDF4-50 where you get down to 2dB loss/100ft at 800MHz.
prcguy

Like I said...not like he's dealing with super high frequency stuff...but nonetheless, LDF and LMR serve their purposes.

If he has the money to use, why not get the better stuff...
 

prcguy

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The thing that bothers me is LDF1-50 is around $1.30/ft retail and it looks like the original poster bought surplus cable for basically retail price. That stuff goes for maybe .25c to .50c/ft surplus.
prcguy
Lowa2 said:
Like I said...not like he's dealing with super high frequency stuff...but nonetheless, LDF and LMR serve their purposes.

If he has the money to use, why not get the better stuff...
 

Lowa2

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If i'm not mistaken, the stuff he is buying is brand spankin new, with connectors installed :)
 

hawkeye32

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yes i can have my choice of connectors this is also with shipping included and as for aircraft bands that i want to pick up is selfridge AFB which is about 40 miles from me, also normal avaition 110-138 mhz , trunking 800mhz As for the terrain not alot in my way no hills tall buildings etc... i am about 4 blocks from the water...but another thing i am disappointed at is i got my ST2 today and it has a normal cable lead in on it, no PL-259 connector on it, but i do have a pl-259 froma old dipole i have here but can't seem to find way to attach it to the ST2..Only thing i can try and find not sure if it is possible but a adapter with a PL-259 ,beings the adapter that is on it now is screwed on by wing nuts, (kinda like the good ol days of rabbit ears hooking up to a tv) same concept, or before our tv's had cable lead ins on it you had to screw this adapter (sorry for not know ing the term) then plug ur coax into it, thats what is on my ST2 , so not sure what to do now, thou i have posted here in the forum requesting ideas about that..But thanks for the responses here
 
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