Andy,
Video ID is nice but when sent horizontal it has a very low average
power so won't work well in poor conditions. The RS ID is sequential
MFSK and will have 100% power. Also the Video ID doesn't automatically
tune in your software.
In MultiPSK it is possible to use both types of ID before a transmission
and this is useful if testing out a relatively unknown mode and you want
others who don't run MultiPSK to know what you are transmitting in and
those that do to automatically switch modes.
The only thing I would warn against is using the Video ID in an ARQ mode
as it adds a significant delay to the switching. ALE400 FAE has the
ability to transmit the RS ID only on initial calls and connects and
then it is turned off for the duration of the QSO. An upshot of this is
that if you know there is a MultiPSK enabled machine on frequency you
can SELCAL it and make the link without the other operator doing
anything. Even if you are off tune the other machine will home in on
your signal and if it is the right call it will respond to you. I have
used this to successfully send John VE5MU an email with a binary
attachment without any intervention required by him. Of course the ARQ
nature of ALE400 FAE means that the email + attachment get sent without
error and you are notified that the sending was successful.
73, Sholto.
Andrew O'Brien wrote:
With Multipsk, FLDIGI and DM780 all using Video ID, maybe that is the
best for now,
Andy
On Wed, May 14, 2008 at 9:58 PM, Rick [EMAIL PROTECTED] wrote:
You know what? I have not used RS ID much as of late and it never even
entered my mind to use this last night. But then again, both stations
need to use Multipsk for that to work.
Are any other programs going to be adding the technology?
73,
Rick, KV9U
Sholto Fisher wrote:
The problem with knowing where to tune any signal can be solved
completely by use of RS ID (as in MultiPSK, PocketDigi etc). It amazes
me we have had this technology for over a year now and very few people
seem to realize the potential of this.
Even with s/n ratios down around -15dB MultiPSK will successfully lock
on to the center frequency of any mode and also switch to the correct
mode/parameters.
In the real world there is always going to be some mis-tuning and
although the IFK modes have excellent tolerance in respect to this if
someone is 500Hz away they aren't going to decode your transmission,
especially if they can't see it on the waterfall. Sending an RS ID
before will get them on frequency instantly.
73, Sholto
KE7HPV.
