List of KissOZ HW versions as of february 2015
April 2016: The KissOZ HW V4rpi is available for preordering at https://www.tytera.dk (contact shop for international orders)
Since the start, with the AVR CPU, the SAM3S4B CPU we are now on the STM32M4F CPU, and we beleive we have reached the final platform for the stuff we want to play with. Below is a collection of pictures of the past and present versions. The latest beeing the shield/expansionboard for Raspberry PI B+ & PI 2 The V4rpi is not expected to push V4 away, but complement it by making a board dedicated for RPI, which makes it superb for a Digi, iGate or even a tracker with a RPI as presentation backend. The V4rpi has onboard space for a super sense GPS module.
KissOZ HW V1 & V2
MX614 decoding and
KissOZ HW V3
KissOZ HW V4
KissOZ HW V4rpi
New ARM32M4F TNC platform
We have succeded in getting our new platform to perform better than what we could have expected.
We have compared the ARM32M4F TNC with the results from the first modem we made, which was based on the MX614 chip.
The AMR32M4F is a 100% software/DSP based solution, which makes this a 'single chip' solution apart from the necessary opamps and power supplies.
Originally the MX614 based modems would retrieve around 970 packets from the 'standard' APRX TEST CD (TNC_Test_Ver-1.1 track 1 by wa8lmf). With the new HW we achieved 850 packets for a long time, with a sudden jump to 950 packets, which is fair. However the latest achievement reaches almost 1000 packets! (994-998) retrieved from the test track. We are extremely satisfied with this result, and will leave it at that. To pull more packets fromthe CD will probably require some error correction tricks. We do not think that the nature of APRS and the application will benefit from those few extra packets as they are probebly received on a different node anyway.
Another win with this new platform is the signal to noise ratio... the early modems performed down to a s/n ratio down to 8-10 dB, early measurements of the ARM32M4F TNC indicates s/n ratios all the way down to around 4 dB, this will have to be confirmed with some near future measurements.
To sum up - it's just looking very promissing..
Modem / Tracker for APRS.
Controller for analog and digital repeaters
With KissOZ.dk we want to display our projects and provide a little help to fellow radio amateurs, we primarily do this for fun not business.
We have made some +20 modems (06/2013) which are installed on digipeaters.
The thought is 'Why buy? When we can play!". The first modem / tracker is mased on an Atmel AVR 328 with and without an external afsk demodulator chip.Then we made the same with an Atmel SAM3 cpu, the move to this cpu was to get, more space and it is capable of having both modem and tracker functions at the same time.
The latest and hopefully final platform is based on STM32M4F with lots of room in both ram and flash together with a hw floating point unit. This is clearly overkill for doing a modem and tracker - This lovely platform provides the power to do much more, the plans are to make a repeatercontroller, capable of handling various modulation types and perhaps linking to a repeater backbone.
The intension is to make the source code available, for the final version we use an OS - ChibiOs, it's light weight and do the job well, it has not been too difficult to acquire this new state of mind, as programming with an OS is very different.
When will anything be available?
Well probably before it is finished, but not before the code is somewhat mature, and in a state where we wont be too embarrassed to let the public in.
Another direction of our projects, is building an entire radio, that can be a stand alone tracker with a output power from 5-40 W depending on the final output stages. Two prototypes based on the two prevoius patforms are already in service for the Copehagen Suborbitals support and launch vessels.
Stay tuned OZ7HVO and OZ1EKD
APRX package for OpenWRT
As a service to the community OZ1EKD compiles APRX for various platforms with OpenWRT