Thursday, August 28, 2003

End of an Era

In the beginning of August, 2003, I had to make a very difficult decision to shut down most of the SWNH <> NHDX <> KEENE AX25 packet node.  This came about because of the new mandates for hardware installation on the new DTV49/CH52 tower.  The new mandates require EVERY feed line to be installed using snap-in cable hangers.  Now this is not a bad mandate, and in fact is long over due, but those hangers cost money!!  I had approached NHOEM quite a while ago, before the new tower construction even began and asked if they had any interest in helping with these mandates, but they didn’t, so, long story short, it’s gone.  Over the past couple years, the SWNH node complex was the ONLY active route from Concord NH into Western Mass via my 9600 baud 430 link that was completely RF based.

Let me give a little history of the SWNH node and how it came to be, what it was, and what it’s going to become.

SWNH initially began as a stand-alone TNC connected to an old Icom crystal controlled radio jammed into an old crusty bent up Ringo Ranger a couple hundred feet up the tower.  This was nothing more than a digipeater back in the mid 80’s.  Pure and simple, store and forward talking to a few other mountain tops on the same freq.  Funny, now that I think about it, 17 years later and that’s what APRS is now….. Huh….

Anyway, by the time I arrived in this area, packet was really just beginning to take off, and it wasn’t long before we were hooking two TNC’s together on the RS232 side and using two different radios to talk to other mountain tops – a real node.  The first “back-bone” was on 220, and until I had pulled the plug, we were still using it to talk to Ascutney and Hanover.  We also changed frequencies to 145.05, off from 145.01.  Now we could go in on .05 here in Keene, step across the back-bone on 220 and come out on Ascutney on .01.  Worked real slick!  Then Ascutney put in a UHF back-bone over toward Concord to come out over there on yet another VHF frequency.  Nodes were popping up all over the place.  Eventually, there were 4 TNC’s, all connected on the RS232 end – through a device called a “diode matrix”.  What the matrix did was to route RS232 signals to whichever TNC a data stream was addressed to, “and” to keep all TNC’s quiet “except” the one that was transmitting – to avoid collisions, ie so no two TNC’s sent data at the same time.  Made for much better through-put when data was heard correctly the first time – very much “unlike” APRS – errr, I mean digipeaters.

The node continued to grow, adding a local computer for a BBS (Bulletin Board System) and 5 more TNC’s for a total of 9 TNC’s and the computer.  We ended up back at the height of packet activity with a VHF user port – SWNH, a UHF “server” port – SWNHU, a DX-Cluster access point – NHDX, a general node stepping point – KEENE and the BBS – BBSZYX.  We also needed two diode matrix boards because we had so many TNC’s running, they would have been too loaded down (not enough RS232 signal) to have just been connected together, so the node was actually broken up into two node stacks.  One side for User/Server ports, and the other for node interconnects – backbones.

If anybody wants to see the node in action, including the BBS, just let me know, I video taped it showing all the blinking lights…  Pretty cool!!

Eventually, as time progressed, and packet didn’t, Nodes began disappearing, backbone links were becoming more intermittent, BBS’s just had outdated bulletins and hardly any personal mail – The internet had arrived.  Servers went away, Users went away and eventually entire nodes went away.  And now, unfortunately SWNH/SWNHU/NHDX/KEENE joins the ranks of “nodes that used to be”.

I suspect that I will put one or maybe two TNC’s back on the air, I just haven’t decided on what frequency or what service it will perform.  Maybe I’ll leave it on it’s current freq, maybe I’ll put it on the DX-Cluster freq, who knows, only time will tell.  The plus side is that the antenna at 300 feet that used to be fed with 9913, now has a run of 1 5/8 heliax going to it!  So, if nothing else, it’s going to be a valuable antenna location for something!

And if you’re interested in just reading about the node, there’s still an old web page out there but I wrote one with most of it’s contents located at:  http://www.ccdx.org/scrapbook/SWNH/swnh.htm

Joel – WA1ZYX

Monday, September 10, 2007 10:05 AM