[Lf] [Fwd: LF: DF0WD decoded/ External ADC/ Wolf Beacon sigs]

[Andre' Kesteloot]

James Moritz wrote:

> Dear LF Group,
>
> Based on DL4YHF's description of his BPSK TX, and measuring
> the frequency of the DF0WD WOLF-mode signal, I was able to re-
> calculate the command line parameters for WOLF, and decode the
> recorded signal from last Sunday as "M0BMU WD TNX 73". The
> power level Wolf was using produced decoding within the first
> frame of data, so lower power could easily be used.
>
> Rik's idea of an external ADC board for DSP software is nice -
> however, some interface circuitry would be needed to connect the
> ADC to the COM port. In practice, this interface might as well be a
> DSP processor, which could then pre-process the high-speed ADC
> data to alleviate the bottleneck caused by the COM port. Different
> software could be downloaded to the DSP from the PC via the
> COM port. In fact, the overall arrangement would be much the
> same as the DSP evaluation boards offered by people like
> Motorola, Analog Devices and Texas, the main difference would be
> the provision of a high accuracy clock source. It might be possible
> to identify an existing board which could be easily modified.
>
> I hope to run a WOLF - mode signal this evening from about
> 2000utc. I will start at 300mW ERP, then after an hour reduce to
> 30mW ERP and leave it running for a couple of hours. As before, I
> will transmit a carrier for a few minutes at the start of each 1/2
> hour. I will transmit on 137.4400kHz for a change, in case anyone
> is trying to use 137.5kHz.
>
> Cheers, Jim Moritz
> 73 de M0BMU