900 Mhz ham radio

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In the ARRL directory 900 Mhz section you see only a (-) for the input section can anyone tell me what is the standard off set for ham radio frequencies in the 900 Mhz. Or what does the (-) mean?

Is there any 900 Mhz radio’s for the ham radio? And how much do they cost?
 

hamstang

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I believe the minus 900mhz repeater offset is 25mhz. Currently there are no 900mhz ham radios other than mostly Motorola and Kenwood radios which usually have to be slightly modified for the ham radio repeater split and sometimes improve receive sensitivity. A search on eBay will reveal a lot of 900mhz radios for sale, usually for $200 or less. Only certain radios can be modded for ham use which the eBay ad will usually note. I use the Kenwood TK-931 for base operation with the 2 local 900mhz repeaters. Alinco is rumored to have a 220mhz/900mhz hand held arriving on the market this month.
 

fineshot1

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There are two standard offsets for the 902-928MHz shared ISM/Ham band.

There are the -12MHz and -25MHz tx offsets.

The -12MHz offset came about first and is more difficult to modify commercial
equipment to transmit and receive.

The -25MHz offset came about later due to it being easier to make the moto
and kenwood commercial radios transmit and receive closer to their original
commercial band plan.
 

W2NJS

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The later (25 mHz split) band has its repeater inputs on 902+ mHz and outputs on 927+ mHz. I run an old ten-channel Spectra at about ten watts to a tall fiberglass vertical into a repeater that's about fifteen miles from my house.
 

MarkWestin

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The Alinco DJ-G29T 220 and 900 dual band handheld has been FCC approved PH3DJ-29T. It looks just like the DJ-G7. Universal Radio has a page up on it.

Mark
 

stevelton

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I am waiting for the Alinco 220/900mhz hand held to come out. 2 awesome amateur bands in one nice package. And the first actual Amateur 900mhz radio! Now we need the mobile Alinco!!!

Steven
 

N4KVE

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I'm sure before Alinco tools up for a 900 mobile, they will want to see how well the 220/900 portable sells. Anyone remember years ago when the novices got voice privileges on 220? The big 3 made sure plenty of 220 radios were available for the thousands of novices who wanted to talk on ham radio. Well that didn't happen, & it took years to finally sell those 220 radios. Now only Alinco, & Jetstream make 220 mobiles, & rumor has it they are the same radio. The new Alinco radio won't cost a lot to design, as it is based off an existing radio, so only the bands are different. So I'm sure they will be watching how these new radios sell before they plan to make a similar mobile unit. I applaud them for undertaking this project, but I won't be buying this new radio, as I already have 5 Motorola 900 portables, & 2 mobiles. GARY N4KVE
 

jhooten

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I will be buying the new Alinco. All my 900 stuff except the one Spectra mounted in the truck were lost in the fire including the programming equipment. I just purchased on of the Jetstream 220 mobiles. It look well made on the outside. After some more testing if it works well I will get one to use as a base unless the Alinco dual band mobile come out first.

Now to get the 900 and 220 repeaters built and find tower space for them.
 

zz0468

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There are two standard offsets for the 902-928MHz shared ISM/Ham band.

There are the -12MHz and -25MHz tx offsets.

The -12MHz offset came about first and is more difficult to modify commercial
equipment to transmit and receive.

The -25MHz offset came about later due to it being easier to make the moto
and kenwood commercial radios transmit and receive closer to their original
commercial band plan.
The 12 MHz offset came in the original ARRL band plan, and for most areas worked out to be unusable, as is the case with most ARRL band plans. The defacto standard is 25 MHz, and now in southern California, there is 25 MHz and 22 MHz offsets, which was done to accommodate more pairs after Teletrack'S 900 mhZ SYSTEM was shut down.
 

KE4NYV

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The -25MHz offset came about later due to it being easier to make the moto
and kenwood commercial radios transmit and receive closer to their original
commercial band plan.
Not to mention, made tuning a 900 MHz duplexer MUCH easier to tune and play nice.
 

JASII

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900 Mhz Ham Radio

I posted something in another area and then I ran across this. If I want to get gear for the 900 mHz band, can a family member legally operate at 1 watt or less as it is ISM or are their restriction on what gear that can be used? What I am considering is gear that can be used by my wife and I, who are hams, but that could also legally be used by other family members at 1 watt or less under the ISM band rules. Is there any field programmable Motorola portable transceivers that would do this? It looks like the XTS2500 ,ight do this.
 
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zz0468

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I posted something in another area and then I ran across this. If I want to get gear for the 900 mHz band, can a family member legally operate at 1 watt or less as it is ISM or are their restriction on what gear that can be used?
Your family could only operate equipment certificated for Part 15 non-licensed operation. It would not be legal to take a commercial radio, for example, crank the power down, and have them use it.

What I am considering is gear that can be used by my wife and I, who are hams, but that could also legally be used by other family members at 1 watt or less under the ISM band rules.
Why not get the rest of the family licensed? The technician license is pretty easy to obtain.

Is there any field programmable Motorola portable transceivers that would do this? It looks like the XTS2500 ,ight do this.
No.

What you'd be looking for is bubble pack type radios built for part 15 operation. They're out there, and there are some pretty sophisticated ones, including spread spectrum radios. That's what you need.
 
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