[FADCA] Whodunit on the Florida Layered Network

[bud Thompson]

Deltona
Wednesday Nov 6 0545EDT

Ham Radio Proverb #23:  When two hams can't work each other very good over
an RF path and equipment troubles are suspect - it's always the other guy's
gear / installation at fault -  Never yours.

Perhaps this message could have been titled subject:

"One to remember"

"It could happen to you" or

It' usually the other guy's fault"

"Gotta watch your back", or

"Circular logic is like a boomerang", etc, etc.

BACKGROUND:  We have three network switches - Daytona Beach (ROSE), DeLand
(FPAC), and Orlando (FPAC).  DAB links due north to St Augustine and ORL
East SE to #COA (X1j) digi to Melbourne (once Melbourne is back on the air).
They
are situated about like this mini -map

                           STA


                            DAB

DEL




ORL

                       #COA


At DAB, DEL, and #COA (X1J Node) vertical antennas are used on the old
223.420 flat network. At ORL a 5-el 220 beam is used to get to #COA.
The 220 beam is on the same 35-ft mast as the UHF beam to DEL.  UHF beam
azimuth is about  N 5degrees E and the 220 beam azimuth N 105 degrees S.
All this provides first-try backbone linking from DAB to #COA 24/7.

Early Thursday Oct 31 ORL could no longer link with #COA. #COA had not been
heard by DAB or DeLand for a while.

#COA must be down.

I knew it - the other guy's fault.

By late Thursday the 220 link from DeLand to DAB would not work - or only
once in a while.

A trip to the DeLand site Friday Nov 1st  revealed a solid on-channel
carrier (no tones) on 223.42.  Even though the TNC on that port operates
open squelch, there was so much interfering signal that nothing else could
be heard.

Humm... must be some numbnut's 223.420 network TX stuck on! Arrrgh!

The signal filled the S-meter LEDs 85 % of the time while I watched, only
going down slightly below s9 once in a while.  While I was there I noticed
some activity from DAB - so must not be the DAB 220 radio stuck (I knew it
wasn't one of ours!)  Also noticed one decode from the Ocala 220 switch -
rule that one out.

That only leaves #COA - I knew it, I just knew it!

An e-mail to co-cohort Paul Miller N4WKQ, who can link directly with DAB on
all its ports and make checks, revealed that nothing seemed awry at DAB. (Of
course not, it is one of our switches.)  He confirmed that linking with DAB
on 220 was impossible.

Saturday Nov 2 my partner in crime Charlie N3PPC and I stopped by DeLand to
check things out... The on-channel 223.420 signal was not as strong- but
working the backbone to DAB was still not a sure thing.  Linking to Orlando
on UHF was also now not all that great.

What next? Arrrgh!

What's wrong?  Could be #COA TX stuck on keeping ORL from linking and DeLand
rx tied up... but we normally don't see that much signal from #COA during
the daytime.  Perhaps it is a leaky CATV cable - the DeLand site is in a
condo building that has CATV throughout.

No mater which, it sure is not my fault!

But what happened to the UHF link?  Hummm....

>From home by Sunday Nov 3rd the ORL UHF port could not hear my signal
direct - I'm half way between DeLand and ORL.. and when I forced  a ping out
the ORL uhf port (using the 2M LAN) the signal on uhf was barely audible -
no s-meter reading at all. No wonder ORL and DeLand can't make it.

So now, the ORL UHF can't hear or be heard.  What's wrong?

The entire network from Orlando to DAB was shut down - no backbone service
at all.

Which of the two problems to attack first?

TRIP TO ORLANDO FPAC TUESDAY Nov 5 (after voting)

Stepping out on the roof, the first obvious problem was the mast holding the
two beams had turned in the wind.  The UHF beam was now pointing about N45E
and the 220 beam moved 40 degrees southward.  Could this be the problem for
both ORL UHF to DeLand and ORL 220 to #Coa failures?

Is Life that kind?

Charlie turned the mast back to the normal position while I issued a link
command on the UHF port ! Bingo!  What a relief...

Now over to the 220 port - common, #COA - connect!

#COA - where are you!

I knew it- #COA rig has burned up and can't receive either.  Makes sense -
all logic having been explored earlier.

Then Charlie said, "Why is the PTT LED on the 220 TNC on constant"?

 ... Huh?

Recycled power on TNC - three blinky/blinks from the BPQKISS EPROM - PTT LED
not on. Okay..

Now connect to #COA - PTT LED came on and stayed ON - and so did the 220
radio!

...Huh?

Placing his hand on the 220 radio, Charlie quickly withdrew it with,
"Ouch" -

Turned the 220 radio OFF.

The next network link from ORL to Daytona Beach worked perfectly.

The Orlando 220 port will be down until I check/repair the radio/TNC.

'We have met the Enemy - - and he is us." - Walt Kelly, Pogo cartoonist.


73,
bud N0IA