Antenna update

VK6AHR-3 is now connected to a Comet GP-3 dual band antenna which has just been relocated to the top of our mast as seen in this picture. The mast is not extended at the moment. We are looking forward to seeing how it performs when it is extended to the first stop at ~14m, which will be its normal height when we're not working HF.

Tracker2 updates

I created a script to generate the special telemetry parameter messages which sets up the meaning of all the telemetry readings. This includes the name of the value (PARM), the UNIT of the value (volts, degrees etc) The equation which is applied to the value to translate it back to the original measurement (EQNS) and the meaning of the digital bits (BITS)

:VK6AHR-3 :PARM.Temp,Supply,ADC0,Cnt,HDOP,-,-,-,-,-,-,JP,PR
:VK6AHR-3 :UNIT.DegC,Volt,None,#,HDOP,,,,,,,ON,#
:VK6AHR-3 :EQNS.0,1.9608,-273,0,0.07843,0,0,1,0,0,1,0,0,1,0
:VK6AHR-3 :BITS.11111111,HARG's digipeater status

The first colon means the payload is a MESSAGE, which has to be to ourselves for the telemetry parameters. In our case the first channel is "Temp" (internal temperature of Tracker2) units of "DegC", with the equation values of 0,1.9608,-273 (quadratic). Also all our digital bits are non-inverted hence the 11111111. BITS also lets you describe what the telemetry is for.
By default the T2 monitors internal temp and supply voltage analogues, an event counter which uses the fourth analogue, the HDOP reported by the GPS receiver (GPS not required for a digipeater) as well as the profile jumper and the interrupt/counter input digital bits (the last two bits) There is also a user defined analogue, the third reported analogue value (ADC0 input pin) which is up to the user to interface and supply the EQNS for (the other EQNS are available on the Opentracker wiki) I tested with an IR photo-diode via a resistor to the on-board 5V and it works.

To get all the above in a script requires using the "SECOND" event, incrementing a counter and beaconing those messages at different times to spread the load. To beacon any one of those messages, enter them into the 'T' field of the script editor preceded by the BEACON command (shorten to BEA) so that it looks like this:

"BEA :VK6AHR-3 :BITS.11111111,HARG's digipeater status"

The spaces are important! (one after BEA: and the callsign MUST be padded out with trailing spaces to exactly 9 characters)

Click "Execute T" This creates a script entry which will beacon the message at the appropriate time. Unfortunately there doesn't appear to be a way to copy and paste the script so I can't show you the whole script.

You don't need to send these messages very often. aprs.fi will remember them forever until you change them. A local station's software should remember them as well. We're sending them once an hour. There shouldn't be any reason to send them any more often than every 30 minutes.

The end result of all of this is that you will have a telemetry history which means something to anybody who cares to look. Otherwise it's just a bunch of numbers that means something only to those in the know.

I also added a startup event which beacons a status packet of "T2 back online." This more or less puts a marker in to indicate when the T2 has been reset or powered up. Handy for me anyway.

Tracker2 installed

Installed the T2 today. Minimal settings for now.

Pending Tracker2 install

The Tracker2 arrived in VK6 a couple weeks ago but there were delays getting it into my hands. Thanks to VK6LD Rob for managing the shared order and Danny VK6ZUK for transporting from Denmark (the township, not the country :-)
Installation of the Tracker2 is this Saturday, 9/10/2010. We are having a general APRS workshop where club members can get involved with the install, see a selection of various other APRS gadgets and ask questions about APRS, what it's for, how it works etc.

We've also started on the installation of the Ultimeter 2100 weather station which has stalled due to cable routing issues. An extension ladder and impact drill will be needed.

It has been discovered that the PSU currently powering the APRS transceiver is generating noise on HF. This is not good since the shack is set up primarily for working HF. There are squeals every 40 KHz or so under no load and the whole HF band is pretty much splattered out when it's under load. I suspect that the reclaimed regulator board in the PSU might be a switch-mode although it didn't look like one. There is no HF noise when the APRS is running from battery. Bugger. I'm working on a replacement. Managing 4.5 amps with my current supply of transformers and components is tricky. I'd rather we didn't have to spend more money.

VK6AHR-3 on air (more or less)

Our club digipeater is now officially on air as of 14/8/2010
Due to the unavailability of the Tracker2, we decided to put up a temporary arrangement. Martin VK6ZMS has lent us his Kantronics KPC-3 (non plus, v8.2) which is connected to the radio we were intending to use. The KPC-3 doesn't support WX so that will come later. Everything seems to be working well considering the current antenna is a homemade j-pole at roof level. We have a good location. The Comet GP-5 hasn't been located at it's final position yet.
According to the Argent Data online purchasing whatsit, the Tracker2 is now available again. Watch this space.

OpenTracker Tracker2 still not available

Well it's been eight weeks since the club agreed to purchase a Tracker2. ArgentData were out of stock then and still are now. We should have access to a Kantronics KPC-3 shortly so that will have to do the job in the meantime.

FM92 transceiver under test

One of the club FM92 transceivers is now under test as VK6RN-13 using UIView32 and AGW Packet Engine running on an old Pentium III. The FM92 has the discriminator hack and the "TX audio into the SelCall input" hack. One object 'VK6RN-7' configured in UIView - from aprs.fi:

2010-06-29 08:01:57 UTC: VK6RN-13>APU25N,VK6RTH-3,WIDE1*,WIDE2-2,qAR,VK6GHZ:;VK6RN-7 *290626z3157.75S\11544.30ENNot drowning - just waving
2010-06-29 08:07:58 UTC: VK6RN-13>APU25N,WIDE1-1,WIDE2-2,qAR,VK6GHZ:;VK6RN-7 *290809z3157.75S\11544.30ENExit, stage left
2010-06-29 08:08:23 UTC: VK6RN-13>APU25N,VK6RTH-3,WIDE1*,WIDE2-2,qAR,VK6HGR:;VK6RN-7 _290809z3157.75S\11544.30ENExit, stage left
2010-06-29 08:08:37 UTC: VK6RN-13>APU25N,VK6RTH-3,WIDE1*,WIDE2-2,qAR,VK6GHZ:=3157.75S/11546.00EQ[Testing]
2010-06-29 08:09:08 UTC: VK6RN-13>APU25N,VK6RTH-3,WIDE1*,WIDE2-2,qAR,VK6GHZ:>290610z[Testing]
2010-06-29 08:31:56 UTC: VK6RN-13>APU25N,VK6RTH-3,WIDE1*,WIDE2-2,qAR,VK6HGR:;VK6RN-7 _290809z3157.75S\11544.30ENExit, stage left
2010-06-29 08:38:37 UTC: VK6RN-13>APU25N,VK6RTH-3,WIDE1*,WIDE2-2,qAR,VK6HGR:=3157.75S/11546.00EQ[Testing]
2010-06-29 09:08:37 UTC: VK6RN-13>APU25N,WIDE1-1,WIDE2-2,qAR,VK6GHZ:=3157.75S/11546.00EQ[Testing]

Rob VK6UFO (AKA VK6RN)