[HamWAN PSDR] 1.2GHz to Paine [was: 44.x.x.x HamWAN network at Paine]

[Dean Gibson AE7Q]

Scott Honaker and I have moved forward on this project:

 1. We have installed a gateway (Linksys BEFSR41) between the ID-1 and
    the internal ARES/RACES subnet (not 44.x.x.x) of the DEM.
 2. We have installed a Digi "AnywhereUSB" box to give us remote access
    to the ID-1's USB port, and thus remote control of the ID-1 radio. 
    This not only allows multiple use of the ID-1 (which has useful
    1.2GHz FM and digital voice modes as well as Ethernet data), but
    provides for remote frequency agility and a diagnostic capability. 
    This works beautifully (eg, to search for and use a low-noise
    frequency)!

Unfortunately, what does not work very well, is the RF portion of the 
connection.  PINGs failed at a rate of over 99% when using the 1.2GHz 
antenna at the 70 ft level on the tower, so we swapped the antenna with 
the one used for the Icom 1.2GHz repeater (which wasn't seeing any 
action anyway) at 100 ft.  That made a "dramatic" improvement, as PINGs 
now only fail at a 98% rate (depends upon the time of day, etc)!

Antenna comparison between 1.2GHz and 5.9 GHz for the two sites:

 1. On 1.2GHz, both antennas are omni-directional.
 2. At the DEM, the 1.2GHz antenna is now at the 100' level, whereas the
    5.9GHz antenna is at 150'.
 3. At my home, the 1.2GHz antenna is about 10' above the 5.9GHz
    antenna, and it's on the same line-of-sight path.

Note that voice communication between the two sites using the two ID-1 
radios, is fine (there is a slight bit of noise on FM).

The big difference, in my opinion?  I'll bet that the wireless protocol 
used by the MikroTik radios includes an aggressive error correction and 
retry protocol, whereas the ID-1 is like a piece of Ethernet cable, and 
thus relies on the standard TCP/IP retry mechanism.  The TCP/IP 
protocols, while "unreliable" in the technical sense of the term, 
require a higher overall reliability than a typical raw wireless connection.

What this says (and I'm a bit surprised to note this), is that sites 
considering using ID-1 radios for data communications, may find that 
even with the tighter siting requirements of 5.9GHz, that the latter may 
be more successful (whether or not part of HamWAN).  In addition to 
being a lower-cost radio with a much higher data rate, the MikroTik 
radios offer a built-in router, which can obviate the need for a 
separate router.

-- Dean

ps: The callsign and digital code filtering features of D-Star that we 
previously discussed, are not available (greyed out in the software) for 
digital *data* mode.  Huh?  Another fine example of software of the 
"seven last words" of poor program design: "Why would you want to do that?"

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.hamwan.net/pipermail/psdr/attachments/20140524/84a40b4f/attachment.html>