solar power gmrs repeater

[James_Bond_007]

well a tower site does not appear to be forthcoming in the foreseeable future so i am going the direction of a self contained solar power repeater. i'm thinking of asking the landlord if i can locate it to the back of the property here. i live in scottsbluff, ne in the panhandle to give you an idea of the weather i will be dealing with.

my available hardware is a 10-50w (set for 10-15W) Vertex VXR-7000u-2 (450-470), cellwave 6 cavity bpbr duplexer, 8 bay PD type single inline folded dipole, 40ft push up mast, 1/2 inch 50 ohm hardline with n connectors.

what recommendations would you give me to make this a complete self contained solar power repeater site with emphasis on small land footprint and working within a reasonable budget. see attached pics to give you an idea of what i want to do.

i need a some suggestions of solar panel size and battery capacity as well as low consumption climate control. I'm thinking a compact self contained RV HVAC system that runs on 12/24vDC.

model numbers prices and links would be great so i can formulate a budget for this setup and a design to present to the property owner. i am not against buying or trading for used gear where possible.

from what i can tell i still need a nema enclosure, HVAC system, solar panels, batteries, charge controller, possibly cattle fencing to go around repeater.

 

[mmckenna]

I've got a network of 3 UHF LMR repeaters like this at one of our sites.
10 watts UHF, fully solar.

12 volt air conditioners are expensive, and they'll eat through your power. You'll need a very large/expensive solar panel system to support that.
The sites I have are in white painted boxes, which helps reflect some solar radiation, and all have a small 12 volt thermostat controlled fan in them. Never had a problem with overheating. But, I'm not in Nebraska, so your milage may vary.

Solar panel and battery size will depend entirely on how much the repeater gets used. For light use, something like a 100-200 watt panel might work just fine most of the year. In the winter with shorter days and possible snow cover on the panel, you'll need to adjust sizing. Adding a wind generator may help, but that adds cost.

The three repeaters I have are using these solar systems: SunWize Power & Battery | Remote Power Systems for Industrial
They have a calculator on that site that can help you figure out your panel/battery size.

Not cheap by any means, but they make good stuff. You could design your own system, but unless you have access to cabinets, panels, batteries and the fabrication skills to put it all together, you might do better with a pre-built unit. You will need to be careful with the solar charge controllers, as some of them can be quite RF noisy.

One option to look at for an enclosure is the large "Job boxes" you'll see contractors use. They are heavy gauge steel and pretty durable. I've seen a number of WISP installs use these at some locations. Not glamorous, but they work well enough.

 

[prcguy]

The repeater antenna, feedine and duplexer sounds reasonable to me. You might start by looking up the power consumption for the repeater and I suspect it will use between .5A and 1A on receive and a good 5A on transmit at the power levels you mention. At 1A receive you've used up 24AH per day without even transmitting. If the repeater is keyed 4 hours a day your now at 40AH of battery power used up in 24hrs.

You want to upsize the batteries and solar considerably and you can look up charts on line for your region and how much solar is available during the year. At full sunlight in the CA desert a 200 watt panel produces about 10-11 amps of current using a non buck/boost type controller. An MPPT or other buck/boost converter will make better use of the power and may get you up to 15 amps of charge current in full sun. If you have good sun for 6hrs out of the day that's maybe 90AH of charge you can put back into the batteries and you need to put more in that you take out so 90AH of charging during the day may offset about 60AH of depletion. These are just rough numbers but I would say a 200w panel would be on the very low end for use at my location in So Cal where we have year long sunshine and no snow.

For batteries I would consider at least four 100AH class batteries or 400AH as a minimum. You don't want to use a 100AH battery if the system is going to consume 60AH or more power, you want a lot of overhead so the batteries don't dip below a critical level and you have to plan for running the equipment through cloudy days, snow, etc. I'm no expert in solar charging but have run repeaters and much of my ham station off batteries and solar for 35+ years and have learned from some of my failures.

You might consult with a local solar company to see if they can calculate the needed panel and battery size and there are other things to know like the correct way to parallel batteries so they live the longest life, turning off features on the repeater to conserve power, etc.