What sort of topography? line of sight? What sort of laws apply in your country? How much data? How fast do you need to poll?
I have become a fan of the
Phoenix TWE for unlicensed FHSS 900 Mhz. We use them with add on I/O modules where the processing logic can be remote (simple water well controls and tank monitoring).
We have a customer using the Freewave and they link up and work well, but have not been very rugged. They had two failures back to back simply because of a surge arrestor that my multimeter could detect no problem with.
I think the
Digi XTend (replaced by Xtream) series is more reliable for a cheap 900MHz radio.
For licensed UHF radios, I have only worked with a couple of different brands. For a simple serial radio, we have good luck with
Maxon 174E. It is cheap and simple to configure. I have also worked with
Cal Amp Viper SC400 series and they are probably great if you are an IT guru. They seem to work well and fast when they are working...But then they mysteriously stop ... at random intervals ... but for minutes at a time, then start working again. To my purposes, there is too much "IT" cr*p that seems to go on behind the scenes. When you have trouble with a Viper, be prepared to run wireshark on a managed switch when you call tech support. I spent a couple days last week replacing 8 of them with the Maxon after giving up on getting rid of errors with the expensive Vipers. They may appear on ebay in the not too distant future at a discount price so we can recover some of the money wasted on my time trying to clear up intermittent (but persistent) errors.
The Maxons are dirt simple and cheap and have their own issues...but once you get them working, they work until they die from lightning, then you set up a new one in under 3 minutes, slap it in there for under $400 and away you go again until the next thunderstorm....which will destroy any of them even with good surge arrestors.
We have a Maxon (licensed UHF) with a cheap Yagi antenna pointed at a 4 story hotel, with a 200' cliff right behind it, talking to a water plant 4 miles away over another 200' forested hill. I don't know why it works, but it does with over 90% successful read rate (and polling every 4 seconds, this is fine for this situation). Their stupid HD15 connector for power AND serial sucks and the tiny little mounting holes are a PITA, but I have yet to find a radio that has everything done right...The Phoenix TWE is as close as we have come to falling in love with a radio, but can't shoot through buildings and over hills at ~960MHz and low power (I think it is 500mW).
Being in Bulgaria is probably going to be the single most important factor in your choices. All the airwaves are subject to Gubberment oversight...
