[HamWAN PSDR] SnoDEM status report

[Bart Kus]

I'd like to thank everyone who showed up yesterday for the SnoDEM repair 
+ upgrade work.  It was great to see such a big turnout!

The ground crew did a great job, and kept both the climbers busy 
throughout the day with no stalls of work up on the tower!  The pre-work 
before deploy day (cutting CAT5 to length, pre-terminating ends, 
color-coding the cables, partially assembling the shields, pre-assembing 
the Lookout dish) saved so much time on the day.  So a BIG thanks to the 
few who did this extra task to help make the day a success!

Here's what we managed to do:

 1. Upgraded all sectors to MIMO units, which roughly doubles their data
    rate.
 2. Upgraded all sectors with shields, to minimize crosstalk and
    maximize throughput.
 3. Installed the shielded + MIMO Lookout Mtn dish for that upcoming
    site link.
 4. Upgraded the Haystack dish with a shield to minimize crosstalk.
 5. Replaced ALL the HamWAN cabling on the tower, and secured it with
    proper tower cushions / hangers.  No more zip ties that fail!


We didn't manage to hit 100% of our goals for the day however. Here's 
what remains to be done:

 1. Gold dish still has a broken modem, and needs a shield.
 2. ETiger dish still needs a shield.
 3. "Bruce" dish (no current link, but maybe later this summer) still
    needs a shield AND MIMO modem upgrade.
 4. Cable ladder is missing several cable cushion tie points that need
    to be installed.


My estimate for the speed of cable installation with proper cushion 
hardware was way too low.  This had a few root causes:

 1. I missed the presence of cross-arms all around the tower that
    prevented direct access to the cable ladder by newly hoisted cables.
 2. The general strategy probably had some flaws:
     1. It called for the hauling of CAT5 in 4-cable bundles to each of
        2 heights on the tower.  I figured this would save time by
        having fewer hauling trips up the tower.  It turns out the
        ground crew was really fast at hauling, and that I was really
        slow at anchoring and routing the cable, and even slower when I
        realized I had pulled way too much excess cable up and had to
        push everything backwards to achieve proper lengths.  It
        probably would have been faster to haul up 1 cable at a time,
        set it to the correct length for its destination modem, and
        install the cushions on it.
     2. I split the 2 climbers into 2 teams so each could work on
        independent stuff concurrently at different heights on the
        tower.  While this made some sense, I suspect a greater speed
        boost would have been achieved had the climbers been on the same
        level most of the time.  I spent a bunch of time in tying things
        off just to move around, whereas a 2nd set of hands could have
        easily held something instead.  There were plenty of concurrency
        opportunities at each level, where each climber could have taken
        on the installation of each modem, or splitting work up between
        cable routing and dish replacement, etc.


On the plus side, the time estimates for the ease of sector + dish 
replacement / installation were pretty spot on.

If you have any further insights into what went well or poorly, let's 
discuss it on the deploy@ mailing list.  I only included psdr@ as CC to 
let people know the status of SnoDEM, so please remove it from your replies.

I'll be reaching out to our climbers to see when we might schedule the 
follow-up visit to finish the work @ SnoDEM.

And again, big thanks to everyone who helped!  Couldn't be done without you.

--Bart

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