How does the baofeng radio eliminate squelch tail?

Question

All tests are performed in Carrier Squelch mode on all radios without any sub-audible tone or digital squelch involved.

Scenario 1: The Baofeng handheld radio Keys up. Another Baofeng is listening. When the transmitting Baofeng un-keys, the receiving baofeng does not hear any squelch tail, and has a smooth un-key.

Scenario 2: The Baofeng handheld radio Keys up. A different brand radio is used to receive. When the Baofeng un-keys, the squelch tail is heard through the speaker of the other radio. I have tested this on Kenwood, Alinco, and ICOM.

Scenario 3: A different brand radio keys up. The Baofeng is listening. When the radio un-keys, I hear the squelch tail through the Baofeng speaker.

What is it that Baofeng uses to eliminate squelch tails on the radios where no other brand inhibits this property?

I have confirmed it is NOT chicken burst (ending the PL tone early) , or reverse burst (phasing the PL tone 180 degrees) , and there is something special about the Baofeng radio's "End-Of-Transmission" squelch tail eliminator.

Answer 1

According to the detailed menu descriptions on the Miklor site:

35 - STE

Transceiver - Squelch Tail Elimination

This function is used eliminate squelch tail noise between UV-5Rs that are communicating directly (no repeater). Reception of a 55 Hz or 134.4 Hz tone burst mutes the audio long enough to prevent hearing any squelch tail noise.

Note: When enabled and T-DCS is set to OFF the radio sends a 55 Hz tone for about 1/4 second when the PTT key is released.

Note: When enabled and T-DCS is not set to OFF the radio sends a 134.4 Hz tone for about 1/4 second when the PTT key is released.

Note: Set to OFF before communicating through a repeater.

Note: Recommended setting is OFF

Answer 2

Most squelch tails you have heard are actually caused at the repeater as it tries just for a second to hold onto what might be a marginal signal. When it decides it is lost it cuts off the transmitter.

This is more and more common as agencies like the police move to UHF. I have had more than one officer tell me VHF worked better. (He explained that the repeater was across some water and the tides would affect it, for instance. Not to mention the buildings)