Archive for the ‘APRS’ Category

Kenwood DM710 APRS Setup Recommendations for VK




BAND-B:  Use this band for your voice operations.  Use it on 2m, 440
or even receiving on 1296 FM and many other commercial bands.

CALL CHANNEL:  Save 146.500 MHz voice simplex in your CALL CHANNEL.  
This is important for making QUICK mobile QSO's... The D710 even 
has different CALL channels on the A and B side.

BAND-A:  Set for APRS on 145.175, 1200 baud, TNC on band A.  Set path 
to WIDE1-1,WIDE2-1 in most areas, never more hops without serious 
thought.  LEAVE THE VOLUME UP.  You will control what you hear on 
the APRS channel by what APRS "channel" you have selected.  This lets
the APRS channel be used for data and Voice Alert.

Set band A CTCSS to 100 Hz for Voice Alert with volume up.  Save
in memory 0 or wherever.  Be sure to set Band A squelch way up so 
that the BUSY indication goes out between packets or your rig will 
never transmit APRS.  The tightness has no affect on APRS, but if 
it opens and BUSY shows, the radio will never transmit packet.

radio is practically useless for APRS, because you have to
push-and-hold-1-sec even to access any APRS front panel keys.
Without this, APRS is just too hard to operate for display of
information and becomes just another one-way tracker.

SET MENU RADIO-MEMORY-AUTO_PM_STORE OFF.  Without this, you can not
save your favorite configurations in any of the PM's and have any
hope that they will remain uncorrupted during operation.  The default
is ON, which means that every time you use the radio, it will auto-
matically save (overwrite) your favorite settings with whatever
you were last doing with the radio.  This is bad.  Leave it OFF.
That way once you have the radio configured and saved in a PM, then
you can always go back to that by selecting that PM.

So, now SAVE your APRS configuration in a PM. while the band A
channel is the one with 145.175 and CTCSS 100 for voice alert.

MEMORIES:  Store this APRS/Voice Alert channel with CTCSS 100 in 
memory, say memory 0.  Label it as "APRS VA".  Now turn CTCSS OFF 
and run this open squelch. Save this in say memory 1 with the
channel name of "APRS raw".  Now turn CTCSS ON again, and program it
with CTCSS xxx (your private CTCSS).  Save this in channel 2 for 
example and name it "APRSmute".  With these 3 channels then you 
can easily configure APRS on the fly:

Ch1  "APRS VA " 145.175 Voice Alert, CTCSS 100 for normal operations
Ch2  "APRS raw" 145.175 no tone squelch - for troubleshooting
Ch3  "APRSmute" 145.175 CTCSS 123  - for completely QUIET operation             

The real purpose of channel 3 is if you go to a club meeting or 
hamfest and there are so many voice alert operators that the noise
is bothering you.  DO NOT TURN DOWN SIDE "A" VOLUME!  Instead, set
channel 3 and you will not hear anything.  THe reason for this is
that if you ever turn the volume down, you will forget and it 
might be weeks or months before you realise it and in the mean 
time you were out of voice Contact capability.

If you want, you can also use channel 3 for private calls from 
trusted agents who know your private CTCSS, but then you lose out
on all the Voice Alert activity.  But remember to SAVE your config
in a PM and with the channel A set to the APRS Voice Alert channel
so that every time you start the car, you ARE on Voice Alert.

You can also set in a few digital channels for local DX clusters if
you like using your D7 or D700 for monitoring them.  Then you can 
QSY at any time to a DXcluster frequency and receive DX spots too.

This puts the front panel buttons into APRS function so you can 
quickly hit the LIST or MSG or BCON buttons.

VOICE ALERT:  This was why you left band A volume up but set CTCSS 
100 to mute the speaker.   This way, you don't hear any packets, but 
ANYONE can call you with VOICE on 145.175 to alert you by using 
PL 100.  This allows anyone, anywhere, anytime (they are in simplex 
range of you) to call you by voice with PL100, because they KNOW you 
are listening on the APRS channel with CTCSS 100!

PROXIMITY RADAR:  A corrolary advantage of the Voice Alert Setting is 
that the speaker is 100% muted for all packets... EXCEPT simplex 
range packets from another Voice Alert D700 that is very close to 
you.  His once a minute packets will act like a radar-ping, alerting 
you to his presence and the fact that he is also monitoring voice 
alert for a simplex QSO.
You may go weeks without hearing anyone (simplex packet range is 
only 5 miles or so), but it is fun when someone comes in range.  
APRS is about *facilitating-communications*.  With Voice Alert, you
will never "pass-in-the-night" without knowing that someone is nearby, 
in simplex range of you that can ALWAYS be contacted with a voice 
call...  Its like a free radar for other mobile APRS operators that 
are in simplex range AND listening.

DIGIPEATING:  We do not want most mobiles to digipeat most of the time.
But we do want to be able to use them when needed.  This involves what
we call TEMPn-N digipeating.  See the special web page all about D700 
digipeater settings:

But basically it means:

1) Set UIDIGI to nothing! (we do NOT want you to be a generic digi!)
2) Set DIGIPEATER to ON   (so we can at least digi via your callsign
2) Set UIFLOOD to nothing (so it is not used
3) Set UITRACE to TEMP so that your radio always supports TEMPn-N 


John Hansen has built an external interface box that allows the use 
of any PS-2 style keyboard as a message text entry device for the 
D700.  It just plugs into the D700 mic jack and lets you send 
messages at normal typing speed. 


See also

This feature allows you to place TRAFFIC objects on the APRS system
to alert other drivers of traffic problems, slowdowns and or other
incidents with only two button presses.  This works by changing
your MYCALL temporarily to TRAFFC (or other OBJECT name) and then
sending a few packets to put it on the map.  You put this cofig-
uration in one of the radio's Program Memories (PM5) as follows:

MYCALL:      TRAFFC-4    <use random SSID or match your last letter
XMIT:        MANUAL      <to only report the object ONCE or so
PATH:        WIDE2-2     <keep the OBJECT local
ICON:        STAR        <big & eye catching. (use Triangle on D7).
BAND-B:      146.500      <to hear other locals in the same mess
Voice Alert: OFF         <in otherwords, do NOT set CTCSS 100
By setting XMIT to Manual, you wont keep transmitting TRAFFC objects
if you forget to switch back to your other PM...  But you do need to
push BCON a few times until you are sure that your packet got 
digipeated a few times so that others can see it.

Voice Alert is OFF, so that you will HEAR packets and be reminded that
you are in PM5!  Not only is  Band B programmed with 146.500 for ease 
of communicating direct with others in the same traffic mess, but you
can also then use this PM5 as a quick QSY for "50" at any time.  Thus 
you get triple use out of this Program Memory PM5:

1) One button traffic reporting (push BCON button to actually XMIT it)
2) Quick QSY for 146.50 operations (its also in your band A CALL ch)
3) Quick ctcss disable on 145.175 if I want to listen to APRS channel
4) Possible temporary DIM setting while you get out of the car


SATELITE TRACKING:  If someone in your area is running an APRSdata
server, on your front panel, you will see an alert for any FM
satellites that come into view.  These alerts are transmitted on
145.175 to all Kenwood Mobiles.  They are also captured into your
station list as satellite objects showing you the Frequency,
Doppler Azimuth and distance to the bird.  If your radio has been
on for at least 10 minutes, it will also capture a schedule of all
satellite passes for the next 80 minutes into your DX LIST.

For more info see .

ISS:   ISS with the new Kenwood on board (2004) uses similar path
aliases of ARISS, WIDE, APRSAT also and requires Transmitting and
receiving on 145.825 MHz.  It should also digipeat on WIDEn-N so
that you do not have to change anything from normal operating except
the operating channel to work it.  When operating cia the ISS or
any APRS satellite it is a good idea to add the wildcard "*" to your 
MSG GROUPS so that you can see all of the messages between other 
users.  But dont forget to remove the wild card for normal use or 
your message list will fill up fast on 145.175

SUNSAT, SAPPHIRE, ANDE, RAFT:  These sateliltes also supported APRS
digipeating but are all now inoperative or have de-orbited.

This satellite needs a separate PM because it needs to have
Transmit Data on Band A 145.93 and RX data on Band B on 435.225 +/-
10 KHz fof DOppler and APRS baud rate set to 9600.  It also needs to 
have its own VIA PATH of VIA 4XTECH.  Also, it is a good idea to add 
the wildcard "*" to your MSG GROUPS so that you can see some of the 
messages from GO-32 or other users.  See the GO-32 web page:

AO-51, ECHO:  This FM voice satellite also has a 9600 baud digi-
peater like GO-32 in addition to its more common use as an FM voice
repeater satellite.  It uses the same Band configuration 
as the GO-32 settings so just program a memory channel on band A for
transmit on 145.975 and band-B for receive on 435.150 +/- 10 KHz of
Doppler using the same PM as for GO32.  Do NOT beacon any packet via 
teh voice repeater of AO-51, only via its digital channel.

AO-27:  This FM *voice* satellite is only on during the day but it
is the same as AO-51 though a little weaker on the downlink.  Put
the band-A uplink in a memory channel as 145.85 and the downlink
in band-B on 436.800 +/- 10 KHz of Doppler again, using the same PM 
as for UO-22.  Do not use any packet via AO-27, it is for voice only.

UHF DOWNLINKS:  The frequencies for all the satellites with 
downlinks on UHF are listed above as the center frequency.  You will 
have to tune 10 KHz higher at the start of the pass.  This will shift 
down by 5 KHz 4 times during the pass, so if you use memories, you 
will have to program in several in sesquence to follow the doppler.

In summary I would do it this way:

PM-off - Normal operations with 145.175 in a memory on band A for
         terrestrial operations with CTCSS 100.  Then change channel 
         memory to 145.825 to operate PCSAT (No CTCSS).  Band B is 
         available for all other mobile operations.  Also operate
         Sapphire by only changing your channel freqeuncy and path.

PM1    - ISS operations with 145.825 in a memory on Band A.  You 
         can still use Band B for all normal mobile operations.

PM2    - Satellite operations with band-A memories holding the
         uplinks for UO-22 (packet), UO-14, and AO-27 and Sapphire.  
         Band-B memories hold the downlinks.  Actually, each satelite 
         will probably need 5 memories (+10, +5, +0, -5 and -10 KHz).

PM3, PM4,Available for your other applications or object names.

PM5    - Available for 52 and APRS object reporting...

Just some thoughts...

from WB4APR, adapted for VK by VK4MDX
Categories: APRS

A Ham’s Work is Never Done

My two pursuits of late- my garden and my ham shack are very similar, neither is ever finished and both require constant maintenance.

I’ve been working hard in the garden cutting trenches for irrigation, drainage and some electrics which I will document in my other blog. I have also been working hard in the shack. Recently my Yaesu FT101E went low on modulation on 80 metres and quit transmitting on some bands. I have plenty of other rigs so set it aside to work on another day. That day had arrived.

Some time previously I had changed the valves and done a quick neutralisation and not really tried to use anything but 80 metres on this radio since, so I thought I would start with changing back to the known working valves and doing the neutralisation again, this time with the aid of more testing equipment. I now have an old Oscilloscope and and Audio Signal generator which also allow me to check the RF Processor.

I followed the cold neutralisation procedure and using my scope, I was able to adjust things perfectly, however the rig was still low on power on most bands above 40m. I then decided to go through the full alignment procedure and also the peaking of the RF Processor. After a few hours the old girl was back pumping out better than 100 watts on SSB for all bands except the upper end of 10 meters where the best I could manage was 90 watts.

The next job was to get the old Hallicrafters keyer adjusted. I had used the keyer on the Gnarly CW net the day prior and it was way out of adjustment. A quick tune of the balance and weight had it working as well as it ever has- which is to say it works but is difficult to use- after all it is a valve driven keyer of 1950s vintage. Nonetheless, I can send OK code with it and the other members of the net can read me quite OK despite it’s quirks.





The very next job on the list was the Czech key which had suddenly developed the annoying habit of sticking in the down position, sending a continuous tone. I’ve never been happy with the feel of this key and maybe there was something wrong all along. Unfortunately the contacts are actually impossible to get at and impossible to adjust because you cannot reach them or see them without radical surgery. The resistance is provided by a small conical spring that is not visible, the adjustment of this resistance to anything above nought brought a continuous tone. I pulled the adjustment screw out completely and the key worked perfectly fine at this very low spring resistance. If I tried to close the contact gap, to a gap I was happy with, the key would stick. I settled on a gap wider than I prefer and very light resistance. I am not perfectly happy with it, but the key works. While I had the key apart I bridged the two contacts for the lid, allowing me to test adjustment with the lid open.

IMG_0012 IMG_0005 IMG_0627

Now to the APRS. Since changing USB Serial convertors and reconfiguring the TinyTrack 4 (KISS TNC), I have had problems with Xastir. I just had the setup wrong, but for the life of me could not figure out what it should be. In the end I got it working by reloading the TT4 and setting up the device in Xastir as multiport KISS TNC. I have a wiki that I use to track all of my settings, operating manuals and service manuals etc, but had neglected to put that info in, so spent a few hours getting it sorted. It is definitely working properly now.









Categories: APRS, Daily News, HF, Home Brew

Project- Fill-in APRS Digi for South of Townsville VK4

October 22, 2013 Leave a comment

I plan to get some bits and pieces together to build a fill in digipeater on APRS to fill in a dead spot south of Townsville.

The planned location for the APRS Digi is Mt Inkerman. The location selected has an elevation of 149 m AMSL giving a line of sight to mobiles of about 60k. The Digi should have no trouble hitting VK4RAT on Mt Stuart despite Mt Elliot being in the way, though only a test will tell for sure.


The planned setup is as follows

Transceiver: ICOM IC-25H-50

Antenna: Slim Jim

Stand Alone Digi: TinyTrak 4 by Byonics.

The digi will run from a deep cycle battery and will be be charged by a solar panel.

Categories: APRS

APRS saves a Man’s Life

October 25, 2012 Leave a comment

Ham Radio provides so many great services to the community particularly in emergencies.

You may not be aware that hams also provide communications support for many events in your community- such as Townsville to Magnetic Island Swim, Motorsport such as Car Rallies and Horse Endurance Rides. So next time you see an antenna tower in the suburbs you should think about the service to your community that that tower may be providing.

I am proud to say I maintain an APRS igate and digipeater that feeds location data for hams to the internet. Along with a bunch of other hams like VK4ZZ we provide a very useful service. Along with vehicles, weather events can be tracked and lives can be saved. Weather stations hosted by hams in their backyards feed live data to the internet and are used by many services. To get an idea of what is being tracked in your city, you can go to and type in you location.

Here is a screenshot of Brisbane

Below is a photo of the datafeed on my APRS igate.

Here is just a little bit of what APRS can do.

Lee Phillips went about his Saturday like any other and left the house by 7:30 a.m. to watch the Upperville Horse Show in mid-June, but found himself suffering from a stroke en route to his destination.

Phillips, 66, a resident of Berryville, is a business owner in Purcellville. He is also a radio man, and his friends – who call themselves The Half Timers on air – send out their messages on the airwaves.

When Phillips fires up his amateur radio, or ham radio as many call it, he is immediately connected to millions of people across the globe. That Saturday morning, he turned his amateur radio on to listen to his ham friends talk back and forth.

Phillips started to feel weird and got on his radio to ask his friend, J.B. Anderson, what he thought was wrong.

“I started to feel a little funny and the left side of my face went a little bit numb and I got on my ham radio and I asked J.B. what the symptoms of stroke were,” Phillips explained. “He told me to park my car and call 9-1-1. I didn’t … I drove myself to the hospital, which I shouldn’t have done [and] I slowly got worse.”

Then more people were on the airwaves with him, telling him to pull over. But Phillips turned his car back around and headed to Winchester, since Upperville was too far to drive in his condition.

“I started to go downhill,” Phillips continued. “My face became numb and started to feel real weird. They could tell on the radio that I was talking funny, so I just asked because I knew J.B. was a fire chief and there were some EMT’s on the radio so I asked them. They helped me.”

One person in particular, Adam Forman, heard Phillips talking about his condition. One benefit of the truck Phillips was driving that day was the tracking device installed in his ham radio—an automatic position reporting system, similar to OnStar in some cars.

“I was tooling my way to work and I heard on the radio what the symptoms of a stroke were and people describing it. Lee is a friend of mine and I was just listening,” Forman said.

“I called my wife, who lives in Winchester, and told her to bring up a website that could track Lee’s truck while he was driving,” Forman explained. “Lee has it in his vehicle, it’s called APRS or automatic position reporting system. It’s something that was developed by the Navy. It’s a radio that takes GPS from the radio waves and sends it to a website.”

Forman said the APRS device in Phillip’s truck is used in search-and-rescue operations or for tracking fellow ham radio operators.

His wife made sure that the dot, symbolizing Phillips’ truck on the map, didn’t stop – because that would mean Phillips would no longer be conscious and driving.

“I said, look, if the vehicle stops before it gets to Winchester Hospital, then call 9-1-1 and send them there where the dot [on the map] is,” Forman said.

Phillips was travelling on U.S. 50 and was becoming disoriented about his exact location, but the APRS device knew where he was at every moment.

“It was quite a help,” Phillips said. “By the time I got to the hospital, I was all confused – they kept me going.

“I probably wouldn’t have made it without those guys talking me through it. It was a mistake; I should have pulled over and called 9-1-1. But, being as hard-headed as I am, I didn’t do it. They helped me through it.”

Anderson had called ahead to the hospital to make sure they knew that Phillips would be arriving soon, and in critical condition.

With just one call into his ham radio friends, Phillips’ life was saved. Phillips suffered a mini-stroke and spent 36 hours in the hospital.

“It’s not just that. Even after it happened, I have health issues that I’ve had for the last three years, they’ve come over and helped me,” Phillips said. “It’s not just radio, it’s a big kinship we have on this stuff, we all help each other out and we’re all good friends.”

According to Anderson, amateur radio is a “fantastic hobby” and has a huge impact in situations involving natural disasters or rescue missions.

“The cool thing about amateur radio is that it’s a community of a bunch of geeks. It seems stupid to most people,” Forman said. “But, in this case, here you had an older gentleman who was actually having an event and you had three EMTs on the air talking to this guy in real time and talking him through it.

“Now, was it stupid that he drove himself to the hospital? Yes, probably, but it was important that my wife was tracking him to the hospital … Without that, he could have died in that car and no one would have known.”
Phillips recovered and continues to own and operate The Doggie Wash at Purcellville Pets in Purcellville with his wife Irina.

“It’s a very positive and prominent impact on the community,” Anderson said. “We are a funny group of people and it’s going to be fun when we get together.”

Categories: APRS

2 Meter Indoor Slim Jim Antennas for Cyclone Season and Other Uses.

October 21, 2012 2 comments

Yesterday I needed a new project to take my mind off certain things here, so I set about making a new 2 meter antenna. I’d rearranged my shack again and set it up was follows.

– Icom IC703 for HF (40m) APRS 7036.5kHz using an 80 meter vertical loop. Connected to a eePC running AGWUIDigi to crossgate to VHF APRS.

– Icom 706MKIIG connected to iMac running MacLoggerDX (my favourite for DX Cluster use) and connected to an MFJ1700C antenna switch to a choice of two ZS6BKW antennas or a 43 foot vertical.

– Icom 706MKIIG connected to eeePC running HRD and DM780 (my favourite for PSK) and connected to MFJ1700C antenna switch to a choice of two ZS6BKW antennas or a 43 foot vertical. 

– Kenwood TM201A 2m FM transceiver for VHF APRS (145.175 MHz) using a TinyTrak4 as TNC in KISS mode, and connected to eeePC running AGW UIDigi. The antenna is a home-brew 2 meter J-Pole at 10m metres elevation and using a homebrew 4:1 balun.

Both IC706s have a VHF/UHF outlet unused, so I decided to make use of them by constructing two antennas. I will eventually make a nice yagi for long range 2m and 70 cm contacts but for now I was more interested in local access to the repeater and for cyclone season emergency use. I started looking at indoor antenna options and found some very interesting choices. I wanted something I could work on right away, and get going in an hour or two but that would give OK performance. I came across a description and instructions for slim jim antennas made using 450 ohm ladder line. This style of antenna is a bit like a folded over j-pole, basically a u shaped antenna with a short matching stub. Fed with 50 ohm coax and tuned by moving the coax connection points, it was a very easy antenna to make and I already had all the materials. I ended up making two antennas, one for each 706 radio.

I tested on air and got good reports. I got the SWR down to 1.2 to 1 and the antennas are resonant around 146.5 MHz across a fairly broad range.






Construction of the antennas is outlined in this link.

My construction photos may assist also-

Start with 1500mm of 450 ohm feed line

bare one end as below

then fold over the end and solder as below

Measure 1473mm to the other end and bare the wire from this point enough to fold over as you did the first end.
Measure 1473mm and bare the ends for a bit longer than that.

Fold over and solder that end as well
Fold over

Solder folded end

Now measure 482mm up from the one end (this will be the bottom)and cut one conductor. Measure up a further 25mm and cut again leaving a little 25mm cutout such as below.
Cut out to make the matching stub

Measure up 102mm then remove insulation up to about 155mm as below.

Measure up 102mm then remove insulation up to about 155mm

Strip some coax of your choice- here RG58 since it is a short run- bare two log tails like so.

Connect your antenna to an analyser or transceiver (on low power) with SWR meter. Attach these bare ends to the stripped section using small alligator clips and move them up and down to get the best match – I failed to take a photo of this. But below is a photo of the stripped section to which you attach these bare ends of the coax. Make sure the braid goes to the stub (short end).

Here is my analyser reading- I got better than this eventually with a bit of trial and error. Got X=0 and SWR 1.2:1

Fit a PL259 to the other end of your coax.

Secure the coax as follows. I added some heat shrink over the top, here prior to shrinking and partly removed to show coax fitting.

One of the finished antennas hanging in my shack.

Categories: APRS, Daily News, HF, VHF/UHF

Kelso 40m and 2m APRS Running Again

September 16, 2012 Leave a comment

Now that I am back home and sorted most things radio, I’ve been able to dedicate some time to getting the APRS iGate running again. It operates on 2 metres and 40 meters. The choice of 40m HF is so that standard calls (like me) can have an HF APRS option. HF APRS works great for remote travel. 40m frequency is 7036.5 kHz. You can learn more about APRS in Australia at

My APRS iGate Digipeater uses the following

– Kenwood TM201A on 145.175 MHz
– home made J pole antenna
TinyTrack v4 as standalone Digipeater connected via serial cable and
Belkin USB serial adapter to
Asus eeepc, running
AGPE Packet Engine

– Icom IC703 on 7036.50 kHz connected via
SignaLinkUSB external soundcard, interfaced to
– Asus eeepc, running
– AGPE Packet Engine
– AGWTracker
– 80m Vertical loop or ZS6BKW antenna depending on other uses.

The TinyTrack4 on VHF works as a standalone digipeater, which means it does not need to be connected to a computer. It simply retransmits any received signals via the radio it received them on (after a short delay). When connected to a computer via the serial cable, the received decoded data can be gated to the internet as well- as it is now.

On HF, AGWPE configures the SignalinkUSB soundcard as a TNC, porting the received sound/data to and from the computer. AGWUIDigi allows cross port retransmit so that received HF signals are retransmitted on VHF. This means that if my internet connection is down, chances are the retransmitted signal will be received by a local VHF iGate and gated to the net.

AGWTracker displays the received signals on to digital maps on my computer screen.

Categories: APRS, HF, VHF/UHF Tags: , ,

Some Jobs done today

January 11, 2012 1 comment

Icom IC706MkIIG removed from the Nissan and replace in the shack.
Barrett 950 packed up to send to Barrett for repair.
ZS6BKW No 1 Antenna (random length dipole) rehung took three goes with the slingshot, a few tangles and some swearing.
ZS6BKW No 2 Antenna down for repair
Bushcomm Travelling wave antenna transferred over to HF APRS for now.
Icom IC703 reconnected to iMac for APRS duties (HF 40m)- so VK4MDX-4 back in to full APRS service on VHF and HF.
Old PC Hard drive dead- attempted recovery failed.
Latest build of Ham Radio Deluxe (HRD) installed on eeePC.
HRD Log updated from backup file.
Logbook of the World tQSL digital certificate replacement requested from ARRL- great friendly reply- certificate should not be too far away.
New iMac keyboard purchased and attached to eeePC- now all my keyboards “feel” the same.

Categories: APRS, Daily News, HF