Repeater Installation Help

[njt462]

Hello I hope I am posting this in the right section. I am new to this so please bare with me as I try to explain the set up I have going here. I have three locations all within 3 miles of each other by road. They are listed A B C on map. A and B are built like brick **** houses LOL so the handhelds can not hit each other and C there is no hope of any talk around. The handhelds are 5 watts. We do have two 25 watt mobile radios and can reach from inside building A to almost Bs parking lot. C has a lot of issues even with 25 watts.

Long story short any ideas on the map where I should try and pay rent to install a repeater and how many watts it would need to be to get inside A, B, and C?

I know it all testing and results, but just wondering if anyone would have a ballpark idea. Oh and yes we are on UHF band. The issue with repeater is with the tight zoning laws I have we can only really put a regular tv antenna type height on roof of a location, so sadly building a tower somewhere is not a choice.

If you need more information to try and help me with this project I am trying to complete please feel free to ask. I will be monitoring this thread.

Thank you all in advanced.

 

[K4EET]

njt462, as an ex-Motorola engineer who used to do coverage surveys, I'll say that you may or may not get any "ballpark guesses" but it would be just that, a guess. In reality, if you had a 1,000 watt transmitter, you may not be able to penetrate that building the way you want to. The only way to determine that is with a field survey. I have seen buildings that tend to be "Faraday Cages" that really inhibit radio signals. You may be up against that. If this is a Part 90 business band (or some other business entity that has a budget) question, why not have a study done so that you know exactly what you need? That way you won't go overboard and by the same token, you will also know that the SYSTEM will work end to end.

 

[mmckenna]

You need to provide more information.

No one on the internet can guess what would work without a lot more information. "Built like a brick —— house" leaves too many questions.
One central repeater may or may not work, and the limitations on what you can install further limits this.

An ideal solution would be to either switch to a WiFi based radio and just install enough WiFi access points at each site and all on the same network.
Or, use a small low power UHF repeater at each site that was linked together via a network connection. However, you'll need to make sure your FCC license gives you that option (FB2 + MO) or you'll need to work with a frequency coordinator to get a frequency pair for your repeaters.

Attempting to design a repeater system utilizing opinions from a scanner hobbyist website is not going to result in a cost effective or reliable outcome. You need to contact a reputable two way radio shop to handle the design and proper licensing of such a system.

 

[njt462]

Thank you for your help. One last question is there a general rule of thumb of course subject to all kinds of what if but in general is there is rule of thumb like if outdoor for every 10 feet in air handhelds within 5 miles should be able to get into it? Thus 30 open miles would be 60 feet tall?

I have a frequency coordinator and access to buy equipment, however the science and testing blow our budget. We are trying to do it ourselves, and be like let's do this, then pray.

 

[mmckenna]

is there is rule of thumb like if outdoor for every 10 feet in air handhelds within 5 miles should be able to get into it? Thus 30 open miles would be 60 feet tall?

No, absolutely not. I'm working with a consultant right now on designing a new 3 channel radio system for our PD. I'm spending $140,000 on just the consultant and his design work. He's using some very high end coverage modeling tools with precise 1 meter accuracy ground clutter data to figure out what we need. If it was easy as "10 feet = 10 miles", I would have saved a lot of money.

I have a frequency coordinator and access to buy equipment, however the science and testing blow our budget. We are trying to do it ourselves, and be like let's do this, then pray.

Before you buy anything, make sure your frequency coordination is done and your FCC paperwork is done. Then work with a shop. Buying duplexers online and expecting them to work properly is a well established way to lose hair and sprout headaches.

 

[K4EET]

<snip> We are trying to do it ourselves, and be like let's do this, then pray.

Please take mmckenna's words of wisdom to heart. You are walking down a very steep incline with a lot of very loose, sharp edged gravel. And I'm sure that you fully understand where I'm going with this...

 

[N4GIX]

You haven't told us what service you wish to use? What kind of HTs and mobile radios do you have? Is all this on GMRS frequencies?

Alternatively, is this for a business?

 

[njt462]

We are using baofeng radios as they operate the same as kenwood at under 50% the cost. Most people in the radio room scream when they hear the B word, but we have had good success and the wattage test match box.

We are testing on GMRS for now to see where we need repeater and how much power.

The frequency coordinator said our business should fall into public safety given our line of work so he is gonna try and get a 150mhz and 450mhz license so we have vhf and uhf channel.

 

[K4EET]

njt462, I have to be honest with you, Baofeng radios do not belong in a Public Safety application. If you have liability involved and something really bad happens because of any failure mode of one or more Baofeng radios, the lawyers are going to have a heyday if they find out somebody potentially valued a single human life on a radio that was somewhat less than 50% the cost of a "real" radio that is accepted by your Public Safety officials. Just think how it will sound when the lawyer to the jury when the lawyer drives home the point the cost differential of that radio that failed versus one that was many times more reliable. Even the cost savings of your entire lot of portables may look bad when compared to a human life. May I ask how many portable are we talking about? Is it 25, 50, 100, 250, 500... ?

 

[R8000]

We are using baofeng radios as they operate the same as kenwood at under 50% the cost. Most people in the radio room scream when they hear the B word, but we have had good success and the wattage test match box.

We are testing on GMRS for now to see where we need repeater and how much power.

The frequency coordinator said our business should fall into public safety given our line of work so he is gonna try and get a 150mhz and 450mhz license so we have vhf and uhf channel.

"our business should fall into public safety"
"wattage test match box"

Ok, it's very clear now you are in way way way over your head. You need the help of a local, reputable 2 way radio vendor. Contact one of them for a quote on a system, build up a good working relationship with them and they will be there if there are problems.

 

[TampaTyron]

As a field technician for a large radio manufacturer (specializing in problem systems), a few things come to mind:

You could rent the proposed system type and place the equipment in the proposed location. It should be fairly straightforward to drop a repeater on a rooftop temporarily. This could get you fairly close relative to RF coverage prediction software output (real world vs. human guessing vs software guessing). Alternatively, I have had good luck putting radios in simplex and placing one person near the proposed repeater antenna location (rooftop, man lift, bucket truck, ladder truck, tower climber, etc). If you can talk simplex from each area back to the repeater antenna location with the proposed subscribers, then there is a very high likelihood the repeater location will work.

Dont know the type of use case, but everyone has a mission and a budget. So, make the best use of yours, but keep in mind the B radios have poor performance relative to a name brand radio. This poor performance often requires more system dollars to be spent in order to make up for poor subscriber tx and rx capability.

At the end of day, "One good measurement is better than 1000 educated guesses"!

TT

 

[chief21]

We are using baofeng radios as they operate the same as kenwood at under 50% the cost. Most people in the radio room scream when they hear the B word, but we have had good success and the wattage test match box.

Baofeng radios are a bad idea for any kind of serious application... and that goes about ten times for public safety. And it's not all about "the wattage test"; a quality receiver with industry standard filtering will allow for much better range and intelligibility.

(Same as Kenwood??? Really???)

 

[njt462]

Tampa thank you for the advice we were going to go that route Monday. To the others just because per fcc standards our line of work falls under public safety spectrum applications does not mean we are saving lives or where the radio can be a split second life or death situation. We would never put our employees or company in that situation.

There are numerous online test that kenwood is Japan made and b is China made same underhood just copied.

This thread was just as a science and trial and error of ideas and thoughts from others. It boils down to budget of company. Believe me if we had it the 20k check would be cut to a st louis company to get name brand radios and a repeater system set up, but sadly at this time it is a budget issue.

The company did say 800 up and going drop ship repeater and fcc license if you can find a spot and wattage needed.

800 we can live with 20k sadly no. I do appreciate all the advice you all have given me. We are going to go location site to see where we can get into all three buildings with 8 watts.

If our thinking is correct if we can find a place to get into all 3 buildings with 8 watts if we rent from that place a repeater with 25 watts due to antenna in the air should be golden i would think.

 

[buddrousa]

And the Kenwood's pass real FCC testing. When you go to the FCC site and look up a Kenwood tag you see that radio pictures when you look at Baofang tags you see one radio tested but they sale have several models with the same tag.

 

[R8000]

I just found these locations on Google Maps.

Things aren't adding up here, too many red flags.

I'm out. 73's.

 

[njt462]

Thank you to those who gave help. Your ideas are going to be used. To the ones who are just throwing stones. Its 2020 do you really think those dots are exact locations. Those dots are within 1/2 miles to 3/4 miles. If a few of you must know items off topic it's towing service.

 

[ScubaJungle]

I just found these locations on Google Maps.

Things aren't adding up here, too many red flags.

I'm out. 73's.

@R8000
He literally screenshotted Google Maps in the OP, so what do you mean you "found these locations on Google Maps"... Am I missing something?
Also, why would a location not be on Google Maps?

 

[njt462]

@ScubaJungle

The screen shot was exported to paint and the docts manually painted in which is obvious. You never disclose your exact location online. Which most people never do.

 

[ScubaJungle]

@ScubaJungle

The screen shot was exported to paint and the docts manually painted in which is obvious. You never disclose your exact location online. Which most people never do.

Yes, I understand - I dont understand what he thinks isnt adding up? What are the red flags of using google maps?

Edit: also, the location is clearly exposed by the map, but thats not what Im confused about

 

[TampaTyron]

I would also like to add that instead of purchasing a particular brand, instead purchase the system that a local shop would support. Best case would be to get several quotes from Moto, Kenwood, Etc dealers and select which one is the most trustworthy or competent. An improperly configured or installed system from one manufacturer will always underperform a system that is well designed and installed from another, regardless of who makes the equipment. TT