Repeaters with no PL tone [WAS: W6EK 2M Repeater Failure Update]

Jef - N5JEF

Nathan, if you think having a repeater with no PL tone is interesting, take a look at this info about the Seattle Repeater Group's system:

- Jef  N5JEF

Seattle Repeater Group (SRG)'s highly computerized repeater is located "High atop Green Mountain" eight miles west of Bremerton, Washington on the Kitsap Penninsula. This repeater is owned by the Seattle Repeater Group and administered by Phil, K7PF. It is allocated the frequency pair 146.28/146.88.

The SRG repeater has several unique operating characteristics of which a user must be aware. A half second of audio silence is necessary to start the repeater. A weak signal may not start it, but can answer once the system is up. Any sub-audible tone will totally prevent startup. The repeater possesses a defense against Kerchunking.

The "courtesy" beep (at the end of each transmission") tells users that the repeater is available for use, and that all timers have been reset. It is actually not a tone but a direct FM data burst at 9600 bits per second which sounds like a tone, sometimes. If you have an IBM PC (or clone), with EGA or higher graphics, you, too, can read this data burst, identify users, and tell about the characteristics of each transmission. "

"Kerchunking" (keying up and immediately releasing the microphone button) the repeater momentarily may result in a CW "?" or a "Please Identify" voice message. Nothing will have been repeated.

The repeater is immediately put into AUTOVOX mode and remains there until the next even minute (every two minutes.) Further Kerchunks have no effect.

One must exceed the 2 KHz LOW DEVIATION threshold to start the repeater while it is in AUTOVOX mode. Successful starting cancels the AUTOVOX (until the next Kerchunk, of course.)

On Wed, Mar 11, 2020 at 8:29 AM Nathan Chilton - K6NDC <k6ndc@...> wrote:
When I was in Atlanta, I came across a repeater without a CTCSS/DCS tone listed in RepeaterBook.  I assumed it was an oversight, but then I found that I could activate the repeater by just transmitting on the input frequency without any tone at all.  That's the first time I'd come across a repeater without any input tone.


Nathan Chilton - K6NDC

That's fancy!

Jef - N5JEF

Indeed!  That would be a fun project.  I like the built-in anti-kerchunking and how it enforces good operator practice such as waiting at least a half second before talking. And the elegance of requiring _no_ PL tone. (Of course they have to be the one unique site with no tone...)   The tranmitter fingerprinting is intriguing, and I would really enjoy taking that further by having a group (at least three) repeaters in the area share Time Of Arrival data as well.

- Jef

On Wed, Mar 11, 2020 at 10:10 AM Nathan Chilton - K6NDC <k6ndc@...> wrote:
That's fancy!