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stang
04-04-2014, 11:27 PM
I bit the bullet and ordered the Gainmaster tonight should be here by next friday. Is the LMR-400 coax worth the extra cost? Only want to be buying once. It's about twice the price and I wont be running a lot of power as the gainmaster has a 500w limit. Someday down the road after I can build a tower I might be able to run more power through a different antenna. (beams) Although I will probably leave this antenna up and have them switchable.

Had to order the gainmaster through amazon H&Y is out of stock and DNJ radio's site didn't want to accept my card or paypal.

How high up should I go with this antenna. We are down in a bottom our TV and cell antennas are both roughly 40 ft off the ground. When I do this I would like to put the cell antenna on the same mast 10-20 ft below the cb antenna. Will this cause any problems? It's a small directional antenna less than a foot triangle. The mast will of course have guy wires. And yes I am planning to use top rail for mast I am to old and weak to be using iron pipe anymore. Ideally I am thinking a 60 ft mast with the cell ant. at 50 ft.. Luck me I don't have any neighbors to cause problems.

Thanks

NY714
04-05-2014, 04:19 AM
As high as possible with antenna, and don't push 450-500 thru that antenna it won't handle it, friend of mine ran 500 watts and burnt out antenna in less than one week. Good for 300-400 watts. Definitely the LMR-400 will be the Best but don't get all the knock-off's, get the Times Microwave only LMR-400. The knock-off not nearly as good. MPD Digital is a company on web and Ebay that strickly sells only "Times Microwave" brand and it will work great.

stang
04-05-2014, 07:34 AM
How long can coax be before you start having big loss issues?

Thanks

wi544
04-05-2014, 08:23 AM
google wire gainmaster,, you can make one that will handle more power and be more efficient,, it uses rg-213 for the capacitor and rg-213 for the matching stub and a coax choke at the base just like the gainmaster. I made a few of them forless than $20 each and side by side with the original gainmaster work great could not tell the diff when on a coax switch,,, hang them in a tree or attach them to a fiberglass pole and mount like any antenna.

222DBFL
04-05-2014, 08:24 AM
If you are going to use times microwave lmr400uf, the loss is very minimal to 100ft. Here are some specs from times microwave:
TIMES MICROWAVE SYSTEMS
Electrical Specifications
Performance Property Units US (metric)
Velocity of Propagation % 85
Dielectric Constant NA 1.38
Time Delay nS/ft (nS/m) 1.20 (3.92)
Impedance ohms 50
Mechanical Specifications
Performance Property Units US (metric)
Bend Radius: installation in. (mm) 1.00 (25.4)
Bend Radius: repeated in. (mm) 4.0 (101.6)
Bending Moment ft-lb (N-m) 0.5 (0.68)
Weight lb/ft (kg/m) 0.068 (0.10)
Flexible Low Loss Communications Coax

Drop-in replacement for RG-8/9913 Air-Dielectric type Cable
Jumper Assemblies in Wireless Communications Systems
Short Antenna Feeder runs
Any application (e.g. WLL, GPS, LMR, WLAN, WISP, WiMax,

stang
04-05-2014, 08:34 AM
google wire gainmaster,, you can make one that will handle more power and be more efficient,, it uses rg-213 for the capacitor and rg-213 for the matching stub and a coax choke at the base just like the gainmaster. I made a few of them forless than $20 each and side by side with the original gainmaster work great could not tell the diff when on a coax switch,,, hang them in a tree or attach them to a fiberglass pole and mount like any antenna.

Wish you had told me that before I ordered the gainmaster. Thanks though. I will look it up and check it out.

Thanks

stang
04-05-2014, 08:37 AM
If you are going to use times microwave lmr400uf, the loss is very minimal to 100ft. Here are some specs from times microwave:
TIMES MICROWAVE SYSTEMS
Electrical Specifications
Performance Property Units US (metric)
Velocity of Propagation % 85
Dielectric Constant NA 1.38
Time Delay nS/ft (nS/m) 1.20 (3.92)
Impedance ohms 50
Mechanical Specifications
Performance Property Units US (metric)
Bend Radius: installation in. (mm) 1.00 (25.4)
Bend Radius: repeated in. (mm) 4.0 (101.6)
Bending Moment ft-lb (N-m) 0.5 (0.68)
Weight lb/ft (kg/m) 0.068 (0.10)
Flexible Low Loss Communications Coax

• Drop-in replacement for RG-8/9913 Air-Dielectric type Cable
• Jumper Assemblies in Wireless Communications Systems
• Short Antenna Feeder runs
• Any application (e.g. WLL, GPS, LMR, WLAN, WISP, WiMax,


Any others I should look at or is this about the best? Right now it seems to be a toss up between RG213 and LMR 400.

If I am reading you correctly I need to stay to 100 ft or less?

Thanks

222DBFL
04-05-2014, 08:59 AM
No you don't have to stay 100ft or less. The loss on lmr400 is like 1db over 100ft I want to say, not enough that anyone including you will ever notice. And yes get the times microwave lmr400. Get the UF make (UF=ultra flex) as it is easier to work with. Run it once and be done. This same coax is still in use on most E911 systems in almost every cell site around. It is top notch quality coax and will last a very long time. It is made to handle the elements and weather alike. All of this is JMO, but if you want do some research and I promise you will find that this coax pops to the top of the list for any install. Mobile or base. Like I said, I use the lmr240 that's made by them for my mobile coax and the lmr400 for my jumpers. Overkill, maybe, but I have been told too many times that my mobile sounds like a rolling base station. Like I said before, don't skimp out on anything antenna system related, that goes for connectors, coax, and antenna. Amphenol makes good pl259 connectors that will go onto the lmr 400 nicely. If you want to step it up google Andrew and have a look at their connectors. But for the power you are running, pl259's should work fine. Like I said, get good ones, not the truck stop brand. Take your time making all connections and you will be a happy camper.

stang
04-05-2014, 09:29 AM
Thank you so much this is about what I had concluded. I just want to be sure money is hard earned and spends fast. lol A big part of the reason I am setting this up now is am somewhat of a prepper and IMO things are headed down hill ever faster. Want to be sure we can communicate with others if it gets bad. Not to mention I have been having a lot of fun playing around with this stuff lately. :)

The reason I had asked about length is I have two options for putting this up if I could put the antenna 700 ft away it would be about 50 ft higher and in a much more cleared area. As it is cost wise I think I will have to mount it here at the house.

Thanks again for taking the time and helping out a fellow.

222DBFL
04-05-2014, 09:36 AM
Not worth the effort for 50ft of height, JMO if the run were to be that long I would use nothing less than ldf4-50a. That is a larger coax with a much larger center conductor. It is more for long runs like what you're speaking of. It's not cheap though. Mount a good antenna at the house is high as possible and you will be good. 30-40ft will work fine IMO. My mobile is only 14ft3in to the tip of my antenna and I can talk around the world. It's all about setting your system up right, spend a little extra time, do it right the first time and you will be happy.

NY714
04-05-2014, 10:17 AM
Any others I should look at or is this about the best? Right now it seems to be a toss up between RG213 and LMR 400.

If I am reading you correctly I need to stay to 100 ft or less?

Thanks

Huge difference between the RG213 and Times Microwave LMR-400, can do the 100' run with the LMR-400 no problem but the RG-213 is going to have much bigger losses. RG-217 is more comparable to the LMR-400. I still say the Times Microwave LMR-400 and can go 150' if have to with minimal losses. check the spec's. Or go with the RG-217 Military Spec Coax which is as expensive if not more than the real Times Microwave LMR-400. Good Luck

stang
04-05-2014, 08:32 PM
Well just ordered a 100 ft of the Times Microwave LMR-400 coax. Says allow two weeks for delivery hope it gets here sooner. lol The antenna should be here friday. Now I need to pick up the mast poles, big washers and some u-bolt clamps for the guy wires.

I want to thank you all for your input. I wasn't sure what to get thought this was the best but you all helped make up my mind.

222DBFL
04-06-2014, 04:38 AM
No worries stang, my pleasure to help. Hope you get it set up and I hear you soon on the air waves. 222DBFL, standing by. 73's and god bless.

stang
04-06-2014, 12:31 PM
Soon real soon I hope.

BOOTY MONSTER
04-06-2014, 11:28 PM
for a 100 ft run with just a few hundred watts i'd feel comfortable with good quality 8x with properly soldered connectors . for a 700 ft run using ladder line with 4to1 baluns will have much less loss than any coax.

stang
04-07-2014, 05:01 AM
for a 100 ft run with just a few hundred watts i'd feel comfortable with good quality 8x with properly soldered connectors . for a 700 ft run using ladder line with 4to1 baluns will have much less loss than any coax.

I have no idea what ladder line means or for that matter what a 4:1 baluns is. Can you please explain?

I see you are from my old home town. Somehow I have a feeling I may know you from back in the day.

222DBFL
04-07-2014, 08:31 AM
He asked about some good coax for a 100ft run vs a 700ft run, for 50 ft in height. IMO, that's a lot of money to spend to get 50ft higher. I recommended the times microwave lmr240uf and the lmr400uf. I know it's good coax. It may be overkill, but it's quality coax that will last a very long time and leaves some room for future upgrades.

NY714
04-09-2014, 06:21 AM
Price getting better:

http://www.ebay.com/itm/LMR-400-50-Ohm-Coax-Cable-100-ft-PL-259-CB-Ham-Radio-Antenna-Wire-UHF-VHF-PL-259-/230748923550?pt=US_Radio_Comm_Coaxial_Cables_Connectors&hash=item35b9b5269e

stang
04-09-2014, 06:33 AM
Price getting better:

http://www.ebay.com/itm/LMR-400-50-Ohm-Coax-Cable-100-ft-PL-259-CB-Ham-Radio-Antenna-Wire-UHF-VHF-PL-259-/230748923550?pt=US_Radio_Comm_Coaxial_Cables_Connectors&hash=item35b9b5269e

I bought it off amazon for a bit less. IIRC $118 after shipping for 100 ft. I just looked for it but the listing is gone now. They do have it for $120 though.

stang
04-10-2014, 06:15 PM
Coax came in today says times microwave right on the side of it. Got 7 pieces of top rail for the mast pole and the clamps etc. for the guy wires yesterday. Now just have to wait for the antenna to get here. Funny first piece I ordered is the only one not here yet.
Hope it's long enough should have gotten more than a hundred feet.

stang
04-11-2014, 06:15 PM
Questions Please Help. I have never setup a base station before and need a little help please.

First when I get my new antenna I can set the SWR with the antenna lower down than it will be mounted? Second Will it have to be readjusted when I change radios? Third Both radios I have now have a 1 watt dead key and swing to around 18, do I set the SWR with just a dead key or modulating? Fourth is battery voltage going to be enough to get max power out of the radio? I ask because I have noticed in the Jeep that when the engine is off the signal during modulation is less than when the engine is running. Fifth do any jumpers need to be the exactly the same as the coax? I didn't think to order any LMR-400 jumpers.

I think that's it for now, but there will probably be more questions. Please feel free to mention anything else relevant and thank you very much for any help you can give.

222DBFL
04-11-2014, 07:40 PM
You probably need a higher dead key for a proper swr reading, more around 3-4 watts, no modulation, if there is a mic gain on the radio, turn it all the way down. No you can use rg8x for jumpers. If you have any spare coax left from what you ordered, you can make jumpers from it as well. Remember unless you need every bit of the 100ft, you can cut some back and the swr reading will not change. Length is whatever reaches from point a to point b. Also if you are running directly off of a battery your wattage will be lower most likely as your car voltage normally is around 13.8-14.2v, a fully charged battery might read above 13 volts, but once under load the voltage will drop unlike in the car where the alternator supplies a constant voltage. And as for the antenna, I am unsure as I mounted mine above the roof next to my chimney low and tuned it. Then added more pipe sections. Swr didn't change. I am not a base station expert but I believe as long as you have it up somewhat and able to reach and have an open area you can tune the antenna. More people will chime in I am sure.

stang
04-11-2014, 08:51 PM
Thanks 222 I am a mechanic so pretty familiar with alternator charging. Plus that's how we recharged our battery bank before we got solar. Still do when it stays cloudy for to long. I was afraid of that with almost no dead key wattage. Need to see if I can get one of these radios back up on dead key. The guy who worked on the uniden is going to just love that. Oh well. Will a higher than 4w dead key carrier hurt? Was thinking I could run it out in the yard beside the house and get it on a single section of pipe (10 ft) to set. Think I should find a higher voltage power source. It does seem to make a difference. I just hate the thought of converting 12V to 120 v back down to 13.8 - 14.5 it's such a waste of power. Need to do some research and see if there isn't some kind of multiplier for DC to take my 12 V to 14 V . just what I need more research.

stang
04-12-2014, 08:36 PM
already ordered mine paying much more but here is a gainmaster on ebay for 138
http://www.ebay.com/itm/Sirio-Gain-Master-Hi-Tech-Fiberglass-10m-CB-Base-Antenna-/310927088798?pt=US_CB_Radios&hash=item4864b2dc9e

stang
04-14-2014, 06:43 PM
Well good things do come fedex. lol My new antenna finally got here today.

stang
04-19-2014, 06:58 PM
Finally got it part of the way up. 30 foot so far still a ways to go. Already working pretty well to. Talked to several people in the last hour. Now I need to see if I can get my laptop to work out there where the radio is.

stang
04-20-2014, 07:25 PM
Forgot to mention the SWR 's were 1.3:1 on 1,20, and 40 running the gainmaster strait out of the box and using 100 ft. of LMR-400

hotrod
07-22-2014, 01:42 PM
sounds like its working well