900 mhz equipment in Kansas City

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zz0468

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...Im interested in trying this band but am weary of buying equipment off ebay.
I'm curious what the problem is with eBay? I've purchased quite a bit of 900 equipment that way, and all the sellers I've dealt with have been upfront and honest about what I was buying.
 

newsphotog

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Not much to worry about if you check their feedback. Also make sure that they have previously sold radio equipment and that they received positive feedback on the sale. I have seen KA3IDN sell lots and lots of Motorola radios that he modded to work in the 902 MHz band, and he has 100% feedback. There are some other hams on there that sell almost nothing except modded 902 MHz equipment and they do a good job. As far as I'm concerned, eBay is the easiest and least expensive way to find 902 MHz gear.
 

mgolden2

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Thanks i'll look those guys up and see what they have! Has anyone here ever used 900 mhz equipment? How well does it work? Is the band similar to 2m or
70cm?
 

newsphotog

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Thanks i'll look those guys up and see what they have! Has anyone here ever used 900 mhz equipment? How well does it work? Is the band similar to 2m or
70cm?
Here's some good info on 900 MHz: SD900 MHz About 900

900 MHz is a tough band to operate on. It is almost completely ‘line of sight’. Almost anything can block or hinder communications on these frequencies. Even trees! This is why almost all commercial 800 and 900 MHz systems for two-way communication use multiple linked repeaters to cover an area. Using one central repeater to provide mobile coverage over a huge area of real estate rarely works well unless the site is very high (such as a very tall building or mountain) and the surrounding area is relatively flat and clear of obstructions or multiple receivers and a signal-to-noise voter is used. Many Ham 900 MHz repeater systems are used as a fixed-station entry into another repeater system (such as six or two meters) thus keeping the regular repeater inputs open for mobiles and H/T’s, with the audio between the repeaters allowed to mix together (think full-duplex). Some 900 machines are finding handy use as a fixed station entry point into EchoLink and other VoIP systems.

The band does have some interesting characteristics. It bounces off of mountains, buildings, and other solid objects very nicely. And where you have line of sight, very little RF power is needed for reliable communications. And because of the very short wavelength, antennas can be small, yet be designed with very high gain. Dish antennas were popular to use for this band for point-to-point links, giving very high ERP with tiny amounts of transmitter power. Moonbounce operators like the band for its good EME characteristics. And ducting will sometimes carry signals beyond line of sight.
 

W2NJS

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You should be able to find a decent Motorola GTX900 900-mHz mobile radio on eBay for $100 or less. Out of the box it will not do between 902 and 928 but there is a simple mod to the radio's MDF file that changes the coverage to what's needed for the ham band. Problem is you also need a programming cable, RIB (Radio Interface Box) and software to do the programming. The 900 is 12-watt radio with about 10 usable analog channels; if the listing says more than 12 then the remaining channels are for LTR trunking and of no use to you. Also, the 900 "standard" is narrowband with 12.5 kHz splits. There are also GTX 900 mHz portables which use all of the same accessories as the Motorola GP300 portable.
 
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