Tetra – To pulse or not to pulse?
Airwave claim Tetra doesn’t pulse. They appear to be on their own in this as everyone else claims it does and has evidence to support it. It seems that the only way Airwave can continue to make this claim is by their definition of the word pulse. They claim that their signal doesn’t pulse because it’s wave form rises to a maximum amplitude, then falls to almost zero before it rises again, then falls again etc. Airwave claim for it to be a true pulse it would have to fall to exactly zero before it rises!

Does this seem like semantics to you?

For those who are interested in the technology side, i have come across this excellent description of the Tetra signal by Rod Burman.

“The standard Tetra base station signal we see down here consists of 4 data blocks which constitute a frame and the frames repeat at 17.6 Hz. The signal I see on my oscilloscope trace is almost identical with the one published on page 68 of the NRPB report.

The data within each block appears as a rapidly amplitude modulated signal and there are quiescent periods of approximately 1.78 milliseconds (the SCDB’s) when apparently carrier is radiated without modulation.

The O2/NRPB argument is that because the carrier is still on during the interdata periods the base station signal does not pulse.

My waveforms were obtained by feeding the output from a simple full wave diode detector into an analogue storage oscilloscope and “capturing” several bursts of data.”