SSB on VLF

[Andre Kesteloot]

Charles Brain wrote:

> Hello All,
>
> > The USB signal is intentional. It gives compatibility with RTTY.  I
> > guess we WON'T be using ssb phone!
> >
>
> For anyone that is interested I have implemented a simple NBVM
> system on a 5600EVM that compresses SSB into a nominal 1.2 Khz BW.
>
> I have not tested it on air but I have checked its spectrum with
> a P.C based FFT analyser. I have also recorded it on tape and played
> it back, the quality is quite good. The code runs in Full duplex
> so you can talk to yourself if you want! It only took an afternoon
> to write so it probably has some bugs.
>
> The code is available if anyone wants it.
>
> I believe there is going to be a mention of it in TT next month.
> I made a slight mistake in the block diagram I sent Pat. If he
> prints it I will be interested to see if anyone notices (or cares).
>
> NBVM was discussed in the January issue of TT.
>
> - Charles G4GUO