> Since the window is about 2.7 kHz wide, a JT65 signal is about 220 Hz
> wide, and signals can be decoded with some overlap, at least a dozen
> signals can simultaneously call and be decoded.
Jim is slightly optimistic. The "nominal" audio frequency for the
JT65A software is 1270.5 Hz and the "window" is +/- 1000 Hz (see: pg
35, JT65-hf-setup.pdf distributed with the JT65HF package by W6CQZ).
In practice most transceivers do not work very well in the bottom 200
Hz or so of the "window" due to IF filter roll-off leaving room for
8 to 10 signals maximum.
73,
... Joe, W4TV
On 6/11/2012 4:21 PM, Jim Brown wrote:
> On 6/11/2012 1:02 PM, Mike Waters wrote:
>> On another subject, you may be able to hear RI1ANF (South Shetland Islands)
>> after dark. I've heard him to the SSE the past two nights on 1826.5 through
>> the lightning QRN. K3JJG in PA was copying him better than I was.
>
> This would be a great application for JT65A, which could allow many NA
> stations to work him.
>
> The traditional way to call someone on JT65A is to zero-beat them on the
> waterfall. The better way to call a DX station is to NOT zero beat
> them, but rather to spread out like a split pileup. Since the window is
> about 2.7 kHz wide, a JT65 signal is about 220 Hz wide, and signals can
> be decoded with some overlap, at least a dozen signals can
> simultaneously call and be decoded. JT65A activity on 160M is from
> about 1838.5 - 1841.2, transmitting by feeding a USB transmitter with a
> carrier of 1838 kHz.
>
> The software of choice is JT65-HF. It is freeware, well documented in a
> pdf, and very easy to use. A QSO typically takes 5-6 minutes to complete.
>
> 73, Jim K9YC
>
>
> _______________________________________________
> UR RST IS ... ... ..9 QSB QSB - hw? BK
>
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UR RST IS ... ... ..9 QSB QSB - hw? BK
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