[drats_users] D-rats Transfer Settings

[Dan Smith]

Hi Larry,

> We all seem to need some direction as to standard settings for
> repeater vs simplex file transfers.  Our repeater appears to have
> great Chat capability, but suffers during file transfer requests.
> There's a definite problem during multiple access requests.

Well, a couple of things to keep in mind here:

Chat packets are usually short, which is probably why they're going
through more than larger file transfer blocks.  Try lowering the block
size to see if that helps.

If you don't have a very strong link, then a larger block size gives you
more exposure to corruption.  Remember that voice quality is no
indication of data quality.

Also note that there is a significant delay between when a station keys
up and when the repeater starts to transmit.  This effectively means
that in a repeater scenario, *every* station is a hidden transmitter and
thus you really have no hope of radio-assisted multiple-access.  You can
try turning on the transmit delay in D-RATS.  If you set it to a
negative value, then it will randomize the delay to try to help with
multiple access.  However, in general, you're going to have trouble
trying to multiplex the channel too much.

If it works as expected on simplex, then that means your equipment and
software is working properly.

> Are there published standard settings.  What variables do what in the
> Transfer Settings?

It's been discussed here at length before, so you might check the
archives.  Also, there is some discussion in the configuration section
of the manual:

http://www.d-rats.com/documentation/3-manual/12-configuration/#UserManual0.3.Transfers_Settings

I'll let others chime in here on what settings they use.  I don't really
do data through the repeater (and definitely not through a gateway) on a
regular basis, so I'm not the best person to ask.  When we do data
through our repeater here, we are the only ones on the machine and
coordinate transfers to avoid stepping on each other.

I have found that a centrally-located D-RATS station that everyone can
reach works rather well as a store-and-forward repository for messages
and files, and usually is much more efficient than an actual repeater.

-- 
Dan Smith
dsmith#danplanet.com, s/#/@/
www.danplanet.com
KK7DS