best cable for the job

[johnny1225]

i am putting in a analog mototrbo repeater uhf 450-470 mhz. My question is that this is a construction company that has a 5 year project at a large train station. They are working in the basement so it is all concrete and only one level. We are looking about 1500 ft of cable to do this job and i was wondering if anybody had some good ideas for cable, 1/2 foam heliax or 7/8 foam heliax or something different. antenna suggestions would be helpful too...... i was think 1/4 wave salt and pepper shakers? Any suggestions would be helpful....


thanks in advance

john

[Jim202]

Sounds like your way over your head by asking for help on this. It's going to take much more detailed info before you can plan anything from what you have
supplied us with here. You haven't even spelled out what is trying to be covered.

Jim

i am putting in a analog mototrbo repeater uhf 450-470 mhz. My question is that this is a construction company that has a 5 year project at a large train station. They are working in the basement so it is all concrete and only one level. We are looking about 1500 ft of cable to do this job and i was wondering if anybody had some good ideas for cable, 1/2 foam heliax or 7/8 foam heliax or something different. antenna suggestions would be helpful too...... i was think 1/4 wave salt and pepper shakers? Any suggestions would be helpful....


thanks in advance

john

[escomm]

At 450MHz, LDF5 (7/8" Heliax) loses .808dB per 100 feet. That means you will be losing 12dB from your coax alone.

[Jonathan KC8RYW]

What if the feedline becomes the antenna? Andrew Radiax.

[johnny1225]

it is a basement all concrete that is basically a city block, the only thing they want covered is the basement and that is it, one level not going up or down, it basically goes 900 ft one way and then branches 300 ft one way and 300 ft the other way almost like a T, but where the repeater has to go is at the beginning of the 900 ft run, it can go in the middle of the basement because of the lack of electrical outlets and because of the contruction zone there........

[Bill_G]

Sounds interesting Johnny. I guess it depends on how much the customer is willing to budget for the project. Done right, it can stay behind and be used by the tenant after the contractor leaves. It will probably have to be plenum rated. It will probably have to be surface mounted up out of the way of other trades, and protected where it transits the remodel area. LDF4-50A will give you acceptable performance at 450 but might not be suitable for a cellular BDA afterwards. LDF5RN-50A would be preferred but the installed price could easily exceed $15/ft. If the property owner looks at it as an investment, it will serve them for the life of the building, and cover all bands presently available. Sounds like a sit down meeting to me.