With preemptive digipeating, it'll digipeat on a configured alias
regardless of its position in the path, where normally it'd only take
the next unused address. Say you've got a special digi network set up
for search and rescue operations with the alias SAR - you can transmit
with a path of WIDE2-2,SAR2-2 and if preemption is enabled on the SAR
alias, it'll discard the WIDE2-2 portion and digipeat it using the SAR
alias. The tracker can still be used in a normal WIDEn-N network when
out of range of the SAR digis, but the SAR digis won't pick up WIDEn-N
There's no preemption option on the intrinsic (mycall) alias, though I
could probably force that to be active by default. As for how it works,
the idea is that every T2 is, by default, a digi. If you're in a bad
spot and need a digi to get out, you could identify a nearby T2 and use
its callsign in your path. Likewise, the TEMPn-N alias is enabled by
default for emergency and field day operations.
Deviation, at full TXLEVEL setting, should be around 3.4 kHz. Each
board is checked out on an actual DR-135T using an Agilent 8920A test
set before being packed up.
The T2-135 does have its own pre-emphasis circuit since the DR-135T
transmits data flat, and (D700s aside) that's not the standard for APRS.
It's a bit of a compromise, though, being less than the full 6 dB/octave.
The bottom line is that you shouldn't ever have to adjust the deviation.
If you do find it's out of spec, let me know, but so far I haven't
heard of any problems.
Stephen - K1LNX wrote:
> That seemed to have taken care of it, everything appears to be working
> as it should be now.
> I'm not real clear on a couple of things with regards to digipeating.
> How exactly does "preemptive" digipeating work? Is there any way to
> restrict this to digipeating on mycall only? I'm mainly interested in
> digipeating packets from my handheld, I suppose I could set my own
> alias? How does the digipeat on mycall option work exactly?
> Another question I had was in regards to setting proper deviation. I
> don't know how the DR-135 is setup in regards to the internal TNC, but
> is the TX audio being fed right into a de-emphasis network? If that is
> the case is deviation all that critical?
> On 9/24/07, *Scott Miller* <scott@...
> <mailto:scott@...>> wrote:
> Run the Windows config program (otwincfg) and turn off all profile
> switching options. I'm disabling those all on new boards, since it can
> cause exactly this sort of problem. In particular, the default setup at
> one point was such that it'd switch (using the 'jumper') option
> depending on whether it was plugged in to a PC or not. Very confusing!
> Stephen - K1LNX wrote:
> > Playing with my new OT2-135/DR-135 radio and I am noticing a few
> > that don't seem to be working correctly, or it's user error on my
> > First off, I used the windows utility to set the callsign etc. I then
> > noticed the unit sending out packets with "NOCALL", thought that was
> > kind of weird so I started a terminal session and indeed MYCALL
> was set
> > to NOCALL. Digging a little deeper, I entered the config command
> and it
> > came back with CONFIG 0. I entered CONFIG 1 and MYCALL seemed to
> be set
> > correctly (K1LNX-3) I left config 2 alone (defaults)
> > The other strange thing I noticed is that I have waypoint output
> set to
> > off, but I am seeing this in the console window with received packets:
> > K1LNX-1>APX190,K1LNX-5*,KS4NG-7:=3619.24N/08217.40WxK1LNX - Xastir
> > - Ubuntu Linux
> > $GPWPL,3619.24,N,08217.40,W,K1LNX-1*66
> > $PMGNWPL,3619.24,N,08217.40,W,,F,K1LNX-1,K1LNX - Xastir 1.9.0 -
> > Linux ,a*34
> > Are these waypoint output sentences? Is this normal behavior, even
> > waypoints set to off?
> > Beacon command. I can't get it work. I enter it, it comes back and
> > does not key and send a packet:
> > cmd:beacon
> > BEACON
> > Digipeating does not appear to be working either, or I am not doing
> > properly, or I have a misunderstanding of how it supposed to work.
> > exactly will it digipeat on by default? I sent a beacon from my
> > with a path of WIDE2-2, call is set to K1LNX-7 and it did not
> > I did see the decoded packet in the console however:
> > cmd:
> > K1LNX-7>S6QY2T,WIDE2-2:'n-Dl K\>K1LNX-THD7AG
> > $GPWPL,3619.24,N,08217.40,W,K1LNX-7*60
> > $PMGNWPL,3619.24,N,08217.40,W,,F,K1LNX-7,K1LNX-THD7AG ,x*19
> > I haven't tried remote access yet, and my planned usage is to run
> > in KISS mode in tandem with a HamHUD II in my car, while still taking
> > advantage of digipeating, remote access etc.
> > So far all in all, hats off Scott! Great product :) I can't wait to
> > start running it mobile, I'll report back of my experiences.
> > 73
> > Stephen
> > K1LNX
> > --
> > Stephen Brown - ARS K1LNX
> > Johnson City, TN EM86uh
> > "I use FOSS daily to keep my boxen clean!!!"
> Stephen Brown - ARS K1LNX
> Johnson City, TN EM86uh
> "I use FOSS daily to keep my boxen clean!!!"