)Īlso, this might help for tones in general: However, if both repeaters are transmitting at the same time and their strengths, relative to the user are the same, the interference can cancel out the usable signal. Any user in the overlap can use tone to open the desired repeater and T Sql to theoretically hear the repeater they want. Think of the two repeaters with big circles around them one for each. In our situation, the two repeaters are far enough away so that one is always a weaker signal than the other. If the repeaters are too close, however, the interference might be just too much for it to work well or at all. There can be some interference from the stronger repeater so it's not 100% perfect. So if two repeaters are close to each other and use the same frequency, you could program each repeater into two separate channel numbers and each channel would be programmed with the different corresponding tones, subsequently allowing the operator to pick which repeater they want to use simply by changing channels? Likewise if we want to use the southern repeater.

When we want to use the northern repeater, we use T Sql set to the tone that the northern repeater is putting out. We have two repeaters here, in two different cities, but they are close enough to be heard between the towers. In the case of two repeaters near enough to each other to interfere, a different tone sent out by the respective repeaters means that the user can select which repeater will open their speaker. This is useful in an environment with some considerable radio noise on the frequency where constantly adjusting the squelch knob would be a real pain. Simplex, radio to radio, the transmitting radio would send out a tone while the PTT button is pressed and this would tell the T Sql receiving radio to open the speaker. If your radio doesn't send out the correct 'squelch code', the receiving radio will not play the audio through the speaker. T Sql is 'squelch code' your radio is listening for. The tone is the 'squelch code' your radio is sending out. However, I’m still confused as to what scenario would need a “tone” and what scenario would need a “T Sql”.

Tpl squelch chirp programming