Emergency Communications Team receives Megger TDR500/3 donation
With low amounts of energy, time domain reflectometers (TDRs) fire a quick pulse of energy down a cable – measuring any changes in impedance between the two parallel conductors of a twisted pair or coaxial cable and sending the reflections back.
The instrument automatically graphs the measurement and a map of the cable is populated – illustrating any possible discrepancies between the two wires. The trace on the screen allows the operator to quickly identify the location of the fault.
With telephone and CATV applications, TDRs are especially helpful, as water ingress in twisted pair cables is a big issue. In broadcasting and radio set-ups, the TDR is also used to setup and test either fixed or portable antennas.
For Buzz Kutcher, Assistant Emergency Coordinator for Butts County Emergency Communications, the TDR500/3 was just what his ham radio team needed. Thrilled with the generous donation from Megger, Buzz explained, “TDRs are amazing devices. I have seen a TDR find a dent in a piece of hard-line; it showed the distance to the fault location exactly.” Having worked as a former industrial maintenance technician and aircraft electrician for the US Coast Guard, Buzz was already familiar with Megger’s hand crank instruments. The TDR, however, was a completely new experience.
“TDRs are amazing devices. I have seen a TDR find a dent in a piece of hard-line; it showed the distance to the fault location exactly.”
Buzz Kutcher, Assistant Emergency Coordinator for Butts County
In the event of an emergency like a severe storm, the Butts County Emergency Team of Georgia gets involved - reporting current weather situations to the national weather service via radio and listening in case others need help. Weekly, the ham radio operating team also tests their systems across the county. Practicing all the time is essential for ensuring that the equipment works properly in the event of an emergency.
Now – with a TDR in their toolbox – the team is more prepared than ever.
After recently installing automatic coax cable disconnects, Buzz wanted to see if there was any effect on the feed-lines – with and without the disconnects. Running the TDR showed a very slight bump on the waveform at the location of the disconnects.
“I’m sure the instrument will come in handy for quick troubleshooting and compiling feed-line condition,” Buzz reflected, “Smart phone screenshots can be easily stored for future reference too.”