SOUTH DAKOTA AMATEUR RADIO COUNCIL
SOUTH DAKOTA
LINK SYSTEM
NEWSLETTER
Issue Number Three Saturday, August 18, 2007
Statelink Meeting to be Held In Pierre
The plan is to meet at the Pizza Ranch in Ft. Pierre for
lunch. We will then meet at the new Law Enforcement Training Center at
1330 for a briefing there. Afterwards we can meet at Fire Station #4 for
any additional discussion. We will be monitoring .35 and .73 for any one
requesting assistance while coming in. Remember the time listed is probably
Central Time.
Commercial DB-224 Elements Needed
We are trying to secure commercial DB-224 elements to
convert them to two meters for the SDLink link. We are looking for them
in any condition. If you can get some for more or ever see any or hear of
any let me know please.
Ed WØSD
Updates from
Howard KGØR
In September to October of 2006, three new
CPU cards were built up from available parts when the SD Link was originally
expanded to the west. This was a significant accomplishment because no
cards had been built since the link was expanded in 1996, and we didn't have
any cards that weren't in use to reference the new cards from.
The link had been experiencing lots of extra courtesy beeps since the whole
system was brought back online. Don, AA0F dug into the code and produced
a firmware update to resolve the problem after a considerable amount of
testing, debate, and analysis of the problem. The only problem is that
several of the sites still had the older 68HC05 based CPU's rather than the
68HC11's which could not easily be upgraded.
On October 12, 2006 - Ed, W0SD; Don, AA0F; & Howard, KG0R made a trip to
Reliance to work on the problem. The controller was upgraded with a new
CPU card and the new software load to ensure that the additional key-ups and
courtesy beeps were not generated at the site. At the same time the PL
tone requirement for the VHF repeater was defaulted on to prevent interference
if the power went out.
On the way back from the Reliance trip, a stop was made at the Wessington
Springs site. From our testing we were able to determine that a
significant amount of the key-up/courtesy beep problem was being caused at
Wessington Springs due to the newer radio configuration put in place a few
years earlier. As a result, we also upgraded it to a new CPU card with
the new software load. This resolved about 75% of the key-up
problems. We also evaluated the bent VHF antenna from the November 2005
ice storm.
After upgrading two sites with new CPU cards, some additional cards needed to
be built up so that we had some spares for problems and as templates for new
cards. Four more CPU cards were built up for additional upgrades and
expansion.
Around the beginning of January, after repair and a lot of testing, the Rapid
City UHF repeater and link was moved back into service by Ed, W0SD at its site
courtesy of Rudy, WB0PWA. We are happy to say that it was been working
100% since it has been put back into service, and we've been receiving a lot of
additional activity from Rapid City.
Philip had been experiencing some problems on the west UHF transmit link.
The problem appeared to be temperature related, and occurred when it was very
cold. Ed, W0SD & Dale, WA1RJC also in the beginning of January replaced
the exciter in the UHF transmitter, and it appears to be working 100% so
far. Philip had a new CPU card in it's controller, since it was part of
the original link expansion, but the software load was updated to the new
load. This resolved the last 25% of the key-up/courtesy beep
problems. The link is now double beep free!
Howard, KG0R made the trip up to Garden City in the beginning of January to
deliver a top mount bracket for the replacement VHF antenna. The antenna
and brackets are waiting at the site for the date the tower climbers come for
tower inspection. As of this writing, they had not yet come to do the
inspection. While there, the controller was upgraded to a new CPU card
and the software load was brought up to date as well.
Howard, KG0R stopped by the new Humboldt site (See separate story on Humboldt
site move) and upgraded the controller to a new CPU card. This didn't
affect link operation, but prepared the site for the future. The
controller for the Turkey Ridge site was also upgraded this past spring to the
new CPU card when it was being repaired from the vandalism at the site.
At the same time, it was also configured to indicate loss of A/C power or
battery operation. (See separate story on Turkey Ridge Vandalism).
The upgrade of the Turkey Ridge controller to the new CPU card brings all of
the sites up to the new 68HC11-based controller. This will make future
upgrades and changes much easier. Prior to the upgrades, even call sign
changes would have been very difficult. Jim, KD0S also upgraded the
Pierre controller to the newest software load. Murdo & Terry Peak
will be upgraded to new software loads as maintenance is performed.
After all of the CPU upgrades, we were down to only one CPU card left, and we
wanted to have more available for upgrades or expansion. So parts were
ordered for 3 more cards. Since then, Howard, KG0R has built them up and
we now have 4 available for future use. This is a significant benefit
compared with what was previously available. Work continues on building
up the chassis and other parts to have complete controllers available.
Jim, KD0S and others have been working on several items at Murdo, Reliance,
& Pierre. Murdo had a bad antenna T connector that was causing
problems on the VHF repeater. There was also a bad connection in the
receive audio path that was causing fluctuations in the audio level for
stations on the Murdo repeater. The site appears to be working
well. The Reliance site appears to have both a bad antenna and bad transmitter
finals. As of this writing, the repeater is working, but it is very
difficult to receiving due to the bad finals. It is also operating from a
temporary antenna. Plans are in the works to replace the antenna and
repair the radio to get the site back to 100% operation. The goal is also
to equip the site to indicate loss of A/C power/battery operation if possible.
Lots of other items still await time, attention, and money including:
Replacement of the Wessington Springs VHF Antenna
Installation of batteries at Murdo & Garden City
Replacement of the Garden City VHF Antenna
Installation of A/C power loss/battery operation indication at Humboldt, Murdo,
and other sites
Acquisition, testing, and upgrades of UHF link radios
Alternate power sources
There are plenty of things that need upgrading, but the link is operating very
well compared with a few years ago. Consider donating time and money to
the link. It's donations that keep the link going!
Howard, KG0R
-------------------------------------------------------------------------------------------------------------------------------------------------
USER REMINDER
Remember
with the link going across the state again that there are many links/relays in
the system. You need to PAUSE
for at least one second after pressing the PTT button on your mic to make sure
that all stations hear your transmission. Failure to do so will result in the
first part of every transmission being chopped off due to link system multiple
link key-up times. For the same reason, you must pause between each exchange in
a QSO to allow breaking stations to access the linked system.
Consider Serving on the South Dakota Link Repeater Committee
The
SDARC, South Dakota Link Repeater committee consists of SD Amateur Radio club
representatives and individuals interested in the successful operation of the
South Dakota Link System. If you are interested in serving on this committee
and working on the South Dakota Link system contact WØSIR Dick Neish via e-mail at neish@itctel.com or at his call book
address.
This Newsletter Last Updated on: Saturday, August 18, 2007
Link to Archived
Newsletters