Frequently Asked Questions

What is Spread Spectrum radio?

Developed during World War II, spread spectrum radio 'spreads' rather than concentrates its signal over a wide frequency range within its assigned bands using frequency hopping and direct sequencing techniques. In specific applications like 'hostile environment' or 'last mile' situations where wires can't go, spread specturm will play an increasing important role in a world destined to depend on wireless technology. Get a complete overview of 'Spread Spectrum' by viewing our Basics of Spread Spectrum document.

What kind of distance can I expect from my radios?

There are a number of variables to consider:

  • FREQUENCY: What frequency band do you have to work with?
  • POWER: What is the allowable power output of your frequency?
  • ANTENNA: What is the height and gain of your antennas?
  • CABLE :What is the length and loss of your cable?
  • TERRAIN: Has a propagation study been done for your proposed site?

What kind of Warranty does Simrex Corporation offer on our equipment?

Simrex offers a 1 Year Warranty on ALL products. Optional extended warranties available if required.

How can I check if my SNRDS radios are working?

Basic Communications between PC and SNRDS:

Setup for basic TX test
t Displays test data.
sr D Sets radix to decimal values.
sh 1 Sets number or frames to 1
sl 80 Sets length of packet to 80 characters. Default is 0, number of characters per frame is 256.
sn 0 Sets number of transmissions to infinite. Default is 16 or 1 for Unconnected Transparent.
au Starts transmitting.
ax Stops transmitting.

Setup for basic RX test
oo D Disables connected only mode.
oa --- Must enter 3 dashes to clear filter list addresss.
se E Enables display of what you type.
oh E Enables display of header info.
ov E Enables display of received data.

Once this is set up you should see one line of test data followed by header info. To turn headers OFF - type: oh D. NB: See also "Basic Communication between PC and SNRDS" on download page!