Haha, I had no clue what you were asking about the radio. LOL! As I recall, it's another serial radio like the one you see in the photo. I haven't looked into that cabinet in a long time.
We are currently linking this tower and several other towers and booster pump stations across the city to the main plant which is approx 12.5 miles away from this tower.
I really wanted to use unlicensed bands (900MHz, 2.4GHz, etc) but preliminary path studies show that we would require huge antenna masts to achieve line-of-sight.
They upgraded a couple pump stations and towers to cellular a few years ago, and so far this has worked out ok.
I'm not 100% sold on cellular because 1) I hate the monthly bills and data caps, and 2) as you say, we're depending on a third party to keep their infrastructure functional.
However, a huge benefit of cellular in my mind is the ability to connect remotely to any point (providing the cellular network is working!) and modify code, troubleshoot, etc. I'm the sole in-house tech for this setup (and several other telemetry systems) so reducing travel is a big plus.
Verizon is the best carrier in our area, and they provide some reasonable deals to the local government agencies, as well as excellent speeds and coverage. Their bandwidth should allow me to incorporate security cameras too.
Thanks for sharing your setup. I really appreciate your input!
I meant what sort of hardware is at the other end of the other radio(s)? Since it is licensed VHF, my favorite solution may not work. We use Phoenix Contact TWE (unlicensed spread spectrum 900MHz) radios with slaves that support I/O and can be addressed with Modbus. I actually have one of them being monitored and controlled by a Click up in the panhandle.
It monitors one water tower and controls five water wells and the slaves simply have one combo module hanging off the radio. All the logic is in the Click and the HMI is a Red Lion G306. The combo modules give us 2 digital inputs and 2 digital outputs plus one analog in and one analog out at each slave. The analog signals are 16 bit. This lets me use 100 psi sensor in a lot of cases where I may need to measure towers of various heights with one sensor and plenty of sensitivity.
You really need line of sight or short distances to use 900 Mhz radios. We have some that talk through metal buildings with a "pencil" antenna to a master omni within 100 yards, but more than a 1/2 mile or so and line of sight is pretty important. I think the longest distance I have linked so far is about 9 miles. Our system in the panhandle uses the repeater feature of the radios to allow us multiple path options for one well that we can't quite get line of sight to the master. This is much easier than a 60' tall mast and has been solid so far.
I would be cautious about going purely cellular for control purposes. cellular depends not only on the local providers tower(s) but somebody else's servers and/or communication hardware.
I haven't quoted any fully cellular systems for control yet...monitoring only is not such a big deal, but we get some wicked storms here and I need to be prepared to deal with cell phone outage that could last days...
I recently worked on a VHF system for the first time but all we did was upgrade the control panel and relocate the customer GE MDS radio to the new panel. The customer is very happy with the performance of his radios. It is a small city with antennas like 8 feet high and they all seem to link up through and around buildings and among all the RF that comes with city-slickers.
