Re: Affecting the use of digital modes... #qrm


Matthew Chambers NR0Q
 

But isn't JS8 a keyboard to keyboard mode, why couldn't it slide down to just below the FT8 allocation say to 14.073-14.074, it would fit in alongside PSK?
Matthew Chambers, CBT, NR0Q
Owner/Engineer
M Chambers Communications Engineering LLC
PO BOX 855, Moberly, MO 65270
Mobile (660)415-5620


On Mon, Jun 1, 2020 at 8:19 PM Tom W7SUA <tom@...> wrote:
That will not work Matthew.

JS8 is active and occupies the space between FT8 and FT4.

73, tom w7sua

On 6/1/2020 11:11 AM, Matthew Chambers NR0Q via groups.io wrote:
> Personally I think they should have moved upwards rather than downwards
> as the x.070 to x.074 slice is still sometimes occupied by older
> narrowband digital modes such as PSK31 and it's variants and narrower
> versions of Olivia, along with MFSK. Why couldn't FT8 occupy x.074 to
> say x.078 with an overlap with FT4 from x.076 to x.078 and FT4 only up
> to x.080 for example. I recall that JT65 and JT9 had an overlap area
> with JT65 occupying the lower half and JT9 the upper half of the
> spectrum which worked well. A contiguous block of spectrum would make
> more sense for FT8/FT4 due to the nature of how those modes operate
> where we decode the whole swatch of spectrum at once. And with newer SDR
> technology, we could have a digital-USB bandpass that is 4-6 kHz wide vs
> the 2.8 kHz of most traditional radios, allowing us to see the whole
> FT8/FT4 suband at once. I'm not sure if the direction they were moving
> would allow for that contiguous block. As the number of digital modes is
> only going to continue to increase, finding ways for modes to share
> spectrum is going to need to become a higher priority.
>
> Matthew Chambers, CBT, NR0Q
> Owner/Engineer
> *M Chambers Communications Engineering LLC*
> PO BOX 855, Moberly, MO 65270
> Mobile (660)415-5620
> www.mchambersradio.com <http://www.mchambersradio.com/>
>
>
> On Mon, Jun 1, 2020 at 6:21 AM Tomas, NW7US <nw7us.heliophile@...
> <mailto:nw7us.heliophile@...>> wrote:
>
>     Please see my two articles regarding an urgent issue involving all
>     digital modes on HF, including FT8 / FT4.
>     Part 1: https://g.nw7us.us/3dnf6df
>     Part 2: https://g.nw7us.us/2yQFGfW
>     More parts to follow...
>     Be sure to read the comments left on each post, as there are great
>     points made in this discussion.
>
>     73 de Tomas, NW7US <http://nw7us.us> dit dit
>
>     + https://QRZ.com/db/NW7US
>     + Space weather and radio propagation
>     <http://SunSpotWatch.com> editor for CQ Amateur Radio Magazine
>     <http://www.cq-amateur-radio.com/>, and The Spectrum Monitor
>     <http://www.thespectrummonitor.com/> magazine.
>     + YouTube: https://YouTube.com/NW7US <https://youtube.com/NW7US>
>     + Social Media:
>          - Twitter: @NW7US <https://Twitter.com/NW7US> =
>     https://Twitter.com/NW7US
>          - Facebook (As NW7US): https://fb.me/NW7US
>          - Facebook (As Space Weather and Radio Propagation Page):
>     https://fb.me/spacewx.hfradio
>          - Blog: https://blog.nw7us.us
>
>     ..
>
>



Join main@digitalradio.groups.io to automatically receive all group messages.