Hello all,
I was following the Chinese radio discussion with interest, and I
thought I'd share that I almost exclusively use Simoco UHF and VHF
radios these days, in particular, SRM9005s with a 9025 head. I wanted
to garner some thoughts on their use.
I'll lead the discussion, these radios were selected by myself and my
friend over Motorola and over Vertex-Standard. We were actually going
to go with a VX-2200 on UHF, and I was going to try to get access to
the programming software. I had access to the VX-2500 software at some
point.
One night in discussion with my friend, I'd idly mentioned Simocos,
and he brought them up on a webpage. At this point, I'd never seen one
in real life, and knew little about them except they were 25Watt
commercial radios that should be able to do the 70cm band as well as
Australias "UHF CB" band (477MHz). I'm talking about the 9000 series
here, I've only just borrowed a SRP9100 recently.
My friends said I might be onto something here. Looking into them
myself, I found the programming software is available for free, runs
under WiNE (important for me as a Linux and Mac geek - see my posts on
IAXRpt under Mac OS X 10.7/ 10.8), the radios could be expanded by
means of a "card" that goes under the radio board inside the chassis,
choice of heads, and lastly, I found them cheap - in the UK, far away
from my native Australia.
After a while, myself and my friend, and yup, his father, had a
collection of SRM9000s, and Andrew and his Dad, David, got portables.
Andrew and David fitted an SRM9000 series to their cars. I am bereft
of a car at this point, I buy too many model trains... but anyway, my
units were cheap, as they are both not P25 compatible - as new
condition, open box format. I have found them solid and reliable
radios.
Something I learned later, after I had gotten the radios was that you
could feasibly control them via computer over the control head
interface - a TTL level RS232 serial port! And just recently, after
Jim had introduced me the the RTCM, Andrew and I have decided to make
a "unofficial" expansion card for the SRM series we call "VoterCard."
Its like the RTCM, but adds a GPSDO for full synchronised transmit
capabilities, and a PoE interface for connecting to Ubiquiti
equipment, such as a Bullet or a Loco M2.
Sometimes the most innocent discussions get you into the most trouble...
VoterCard is still on the drawing board. I have most of the parts to
prototype a system, such as the GPS, and an RTCM, but I need a filter
for the GPSDO, and I need to "glue" it together. We're going to use a
uBlox LEA-6T module, a custom designed board to fit in the radio, and
mod the radio itself to change over the LO from local to GPSDO.
Externally, the board will have a network port, a Cisco serial port
(at proper RS232 levels - +/-12VDC) and a GPS antenna connector. The
back of the radio will need to be modified a little bit, but thats ok
- its plastic!
VoterCard was designed for us, for our application of a public safety
radio network, most likely operating on UHF CB, over a large and
mountainous geographical area. The system has to be completely
bulletproof, and able to operate unattended for a number of days. As
an extension, I want this system for my proposed business, so we can
save on mobile phone calls. System health would be monitored from a
central location, ie, the monitoring software whose name I've
forgotten just now.
Now, I've heard of the GPSDO and RTCM thing being done with Motorola
radios, but I ask, wouldn't it be better if the whole she-bang was
*inside* the chassis of the radio? Make it nice and neat, thats for
sure.
So, thoughts everyone? I know Motorola is popular with the Americans,
but have any of you ever used Simocos, and your thoughts on them - and
this plan for VoterCard?
Thanks everyone!
Shane.
