In a previous blog we talked about using Long Tone Zero (LiTZ) to reliably trigger a macro with just a single DTMF digit. Now, how about a system that requires no DTMF at all?
The S-COM 5K, 6K, 7K, and 7330 support a feature known as COR Pulse-Triggered Macro (PTM). PTM lets you trigger a macro by simply clicking your mic button several times in succession.
(Don’t confuse PTM with the antikerchunker, a software feature that prevents noise and short COR pulses – “kerchunks” – from keying the repeater.)
PTM in the 5K, 6K, and 7K works a little differently than in the 7330.
In the 5K, 6K, and 7K, the access mode controls the type of pulses that are counted. If the access mode is carrier, then COR pulses are counted. If the access mode is AND-CTCSS, then both COR and CTCSS must be present in the pulses.
In the 5K, 6K, and 7K, setting up PTM means choosing the number of pulses, their minimum duration, the overall window time, and the name of the macro to be executed. The high level of programmability lets you tailor PTM to suit your application while minimizing accidental activation from noise.
PTM in the 7330 is even more flexible:
• You can assign separate macros for pulse counts from 1 through 9.
• Only COR – not CTCSS – is checked for pulses. You don’t need CTCSS to use PTM, even when the repeater is in AND-CTCSS mode.
• You can choose the minimum pulse duration, the maximum delay between the pulses, and the macros separately for each receiver port. For example, three pulses on RX1 can bring up a link and five can shut it down; a similar cadence on RX2 or RX3 can do something else.
As with Long Tones, PTM can send an emergency tone page, wake up a sleeping repeater, or activate a link to another system.
Where did the idea for PTM come from? It was a feature we added to our line of aviation air/ground interconnects (AGIs). The pilot of a rotary-wing aircraft does not have his hands free to manipulate a DTMF mic. Instead, he can use the PTT button on the cyclic to initiate a phone call or trigger some other action.
In addition, many non-towered airports support pilot-controlled lighting. Clicking the aircraft’s VHF-AM radio mic button 7 times in 5 seconds turns the runway lights on at high intensity. Medium intensity is five clicks, and low intensity is three.
We figured repeater controller owners might find PTM useful. What will you do with it?