Transitioning to a 800 MHz radio system.

Given Auction 16 closing earlier this month, which looked like a Nextel feeding frenzy in the high 861MHz+ channels, I convinced the SMR guy to get us on his system. I told him I’d help build out his SMR 800 MHz channels so utilization would be maximized, maximizing the value of the licenses. I think he thought that was a little forward, but I’ve been pestering him for 18 months now so by frustration or osmosis he’s starting to listen. Sometimes it takes persistence to build a business relationship, I bet this one could be worthwhile.

Anyway it’s pretty cold out but I can use his workbay area to put an 800 MHz antenna on my dad’s vehicle. These radios are 15 Watts and programmed with an EPROM programmer. That’s one “E”, the chips erase via UV! I found that a right angle UHF loses a couple watts at 800 MHz!

Trunking system are a bit surprising to those used to conventional radio. You have to push the PTT button, then wait until a channel is free, which usually takes half a second or so. Instead of PTT and pray someone heard you with conventional radio, in trunking, it’s a closed loop transmission initiation–you can’t transmit unless the repeater heard you and you heard the repeater.

Agencies at all levels are moving this way, the reserved public safety frequencies at 800 MHz and growing noise on low-band VHF have made those 1950’s style systems intolerable. Everything seems have a microchip these days, and as the price of electronics drops it seems the shielding does too. This means low-band VHF is getting hit harder every day. It’s time to move up to 800 MHz trunking!

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