[Lf] [Fwd: LF: 2 Hz shift DFCW]

[Andre' Kesteloot]

Vernall wrote:

> Hi all,
>
> One way of generating a frequency for LF transmitting is to "divide by 100"
> from an HF band.  In New Zealand we work around 181.4 kHz, which
> conveniently means 100 times turns up within the 17 metre amateur band
> 18.068 - 18.168 MHz, so there is no issue with defeating the "transmit
> inhibit" as the frequency is not outside a recognised ham band.
>
> Anyway, the point of this bulletin is to draw attention to the FSK or RTTY
> facilities on modern rigs, whereby applying TTL drive can provide 200 Hz FSK
> for HF packet or PACTOR.  After dividing by 100, that gives 2 Hz shift at
> LF, which is quite suitable for long dot length DFCW.  Other frequency
> shifts can likely also be set, such as 170 Hz, but 200 Hz is the "nice
> number offset".
>
> Even for the EU 136 kHz band, an amateur transceiver tuned around 13.6 kHz,
> divided by 100, could produce a 2 Hz shift at 136 kHz, using the available
> FSK functions of the HF rig (but also dealing with transmit inhibit for
> frequencies outside an amateur band).
>
> This appears to be a convenient way of generating DFCW at LF with a minimum
> of rig surgery.
>
> 73, Bob ZL2CA