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[KE4LYC]

I am looking for a SMALL 1-3 watt 2m FM transmitter kit ( preferably Xtal controlled) to make a micro APRS transmitter setup ..I have a Tink Trak 2 and a Garmin Etrex .. I am try to avoid using a HT. I just need something can lock on 144.390 ..  I know of a PCB design for a motorola chip MC2833 NBFM transmitter .. If any actual can provide the board and parts . Any assistance would be appreciated

[KD5TGN]

I am looking for exactly the same thing.  I am working on a High Altitude Balloon project and need to have the smallest, cheapest, most reliable (I know, choose any two )APRS system I can hack together.

Any ideas?
I am currently in contact with the EOSS group, but they seem to have a bigger budget than I do!

Cheers and 73,
Dan
KD5TGN

[KG6HXO]

Hi! I am about to go to market with a new product. it incorporates a 300 mW transmitter on 144.390, and accepts a Tiny Track III as a plug in. the whole device will measure 1 X 3 inches. It will be offered as a fully assembled board, requiring only soldering in the Tiny Track III and attaching a GPS input. The device ( unnamed as yet) requires 8-18 volts input, has a regulated 5 VDC output to power your GPS, and will weight about one ounce, including the TinyTrack III. It should be perfect for balloons, and should outperform the now, non-existant PocketTracker.

[K9HZ]

KG6HXO... can you send me information on that little transmitter?  bill (at) wjschmidt (dot) com....

[VK2XSO]

It appears everybody has the same idea.
Small APRS tracker.
I'm currently working on my own, which uses a GPS chip, a microcontroller, a crystal and a LiPo 3V battery.
 I can fit all of this into a half a matchbox, and I think I can make it smaller.
 I started with the 300mW modules, but they were too big.
So I went back to a crystal transmitter which gives me 500mW and I can control the power output to save battery power. I've been looking for a PLL to try and reduce the size further. The crystal and the tiny LiPo are the two biggest components. The CPU is SMD, all the components are SMD. They are literally stacked on top of each other.

There are very few VHF PLL chips around these days and the ones that are still around are now discontinued.
 I'm now starting to consider some VCO modules if they are stable enough.

What I really need is an SMD PLL chip and one that can use an SMD xtal. Space is everything. My ultimate goal is to get it all down to the size of a sugar cube, including the battery. The transmitter is holding me back at the moment. I can ditch the PA and go back to ~50mW for good local performance.

[VK2BEN]

Hey VK2XSO; when you are done please let us know how it went! Maybe you could publish  and/or do kits for us lesser non-engineers ;-)

Meanwile, have a look here:

http://www.wimo.com/cgi-bin/verteiler.pl?url=aprs-modules_e.html

Should be good for most land mobile projects where power consumption is not an issue. Quote from the website:
"An on-board 5 volt regulator provides an optional 200 mA power output for your GPS receiver. (Many applications, including the use of the device with hand-held GPS units, will not require the 5 volt output of the Micro-Track.) The entire system runs well on 9-15 volts DC, and draws only about 10 milliamps in standby, and increases to 180 milliamps during transmissions (which last approximately 1/3 of a second using MIC-E). This provides for a very efficient battery-powered package. The transmitter will typically run for about 25 hours on a nine-volt battery with 2 minute check-ins."

Cheers, Ben

[KG6HXO]

We have dropped the MT-300 from production. We have a ton of units left on the EU frequency, 144.800, but all the 144.390 (North American) units are sold out. Most of our products are now frequency agile and have significantly higher power. Our best selling product is the Micro-Trak AIO (All-In-One) that incorporates a frequency-agile 10 watt transmitter, batteries, GPS, and a special version of the Byonics TT3 chip, in a water-resistant Pelican case enclosure. We also include your choice of rubber duck or magmount antenna, and the unit can be powered from unregulated automotive or aircraft voltages. Other than for high altitude balloon use, most people found our 300 mW transmitter a little too anemic. At altitude, its amazing what 300 mW's will do. A group in Canada launched a balloon to 117,000 feet, and the little transmitter was picked up line-of-site from 500 Km away! Since the unit is shipped programmed with your information, its the ultimate "non-engineer" personal tracker! Just add 8 AA batteries and you are on the air.

Allen
VHS/Byonics
AF6OF