Author Archives: VK5ZM

About VK5ZM

Another Ham who was bitten by the Fox Hunting Bug in the early 90's. Participated in numerous National DF championships and likes nothing more than the challenge of finding *any* hidden radio transmitter. Loves to build all of his own equipment, QSO's on homebrew gear is much more exciting than black-box operation. Has been involved in HAB experiments since 2010. Goal is to fill his Toyota Hilux so full of DF gear that he has to buy a Landcruiser.... Approximately half way there.

Rear Diff Repair

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Well after a few months of driving the Hilux it was apparent that all was not well with the rear diff pinion bearing.  It was howling and making terrible noises at highway speeds, it was so loud that you couldn’t talk to people in the back seat.   One afternoon after a run out to Chris VK5CP’s shack at Younghusband I noticed oil coming out of the rear drivers side wheel, so it was now time to fix it.

Upon undoing the nuts on the rear drivers side wheel oil began weeping from the threads, this was not going to be good. Yep just as I feared the inner oil seal had gone and diff oil had run throughout the drum brakes, bugger that’s got to be fixed now.  So once I’d removed all of the brake gizzards the drums were sent off to be machined, over sized brake pads radius-ed and new master cylinders obtained from the local brake repair shop.

The tricky part of this diff rebuild was getting the axles out.  They are quite different from my old Land Cruisers and I again phoned a friend Gary VK5FGRY to help me get it apart.  After removing  the brake lines (oh yay!) and four nuts the axles, backing plate and wheel bearings simply slide out as one assembly.  The wheel bearings were also very growly, so off to the local mechanic with these since you need a press to do the job properly.  Don’t forget to do both sides.  Car stands and a trolley jack are mandatory to do this safely.

Then the fun bit of getting the diff centre out.  That is simply undo 12 nuts and then prepare your self for the heaviest close quarters bench press of your life.  I still cannot believe how heavy the diff centre of the old Hilux actually is.  Anyway once out the initial inspection suggested just bearings would be required, but alas no.   As with all diff rebuilds they tend to be like an onion, once you start peeling the layers back your eyes water more and more.  Anyway for the precision diff stuff I sent it to a local diff re-builder to be looked at.

So a day later I get the dreaded call that tells me the surface hardening on the crown wheel and pinion was completely gone (worn away completely) and the spider gears were wearing on two faces instead of one.  That meant a complete diff rebuild, new crown wheel, pinion, bearings, spider gears etc.  Basically I’d given then a nice diff housing and carrier and well the rest was buggered.  I guess after 410000kms it had simply had enough.

“In for a penny in for a pound” was my Grandfathers favourite saying at times like this, I can still hear him saying it.

So after an eye watering $2300 in materials I was ready to rebuild the diff once and for all.

So the first job in rebuilding this diff was cleaning out the insides of the diff and to remove any previous traces of metal.   So armed with tins of degreaser, white rags and a broom handle we mopped and cleaned the inside of the diff housing until it was as clean as a whistle.

Then the fun job of wrestling the diff centre back into it’s position was tackled.  All nice and black and shiny this time.   I’ll admit installing cleaned parts that aren’t oily is always a nice change and a real turning point in any project.

The new pinion that was installed in the new diff came with a larger input shaft, it’s now 41mm instead of 39mm.  So that should be able to take the additional torque that the new motor puts out, so this diff rebuild is good in that respect.

Once the diff centre is in the axles can be reinstalled and the brakes put back together.  I really like the way in which Toyota prevent you from damaging the inner oil seals, hard to explain but the axles can’t hit the seal while your sliding the axle back in, it’s very ingenious and you’ll find out what I mean if you try it.

I spent a fair amount of effort cleaning up all of the brake components and they won’t look like this the next time I service the brakes.  However the proof that I’d done a good job of the cleaning was when we simply used the handbrake to adjust the drum clearance.  The winders when the handbrake is pulled will slowly wind the shoes out until they meet the drum.  The tension between the winder and springs keep things tight and the clearances small, meaning when you step on the brake pedal they actually work.

So from here it was get the other side done, reinstall the tail shaft and wheels, put oil in it and take it for a drive.  Don’t forget the oil, bad things happen.  Again I’d have been lost without the assistance of Gary VK5FGRY, there is no limit to the things that I learn each time we repair this Hilux in some way.  There’s not much of the insides of this old girl that I’ve not seen yet.

I still remember the first time we drove it out and onto the street.  About 100m down the road I say to Gary “do you hear anything” and the answer was “No”.  Cool job done.

So then the real fun of breaking in a new diff starts, being Mr Goody two shoes for the first 500kms, keep the speed down, don’t flog it up hills, no wide open throttle etc were obeyed.  After 1200kms the diff oil was then changed (yes I was 200kms late).  So far so good, there have been no subsequent leaks and the whole car has changed, it drives just like a new one.

Shed Project – The Main Event

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With the retaining wall out of the way I could get the shed builders in.   This is the first time I’ve not assembled my own shed, I wanted this shed done fast, in total it took 4 days for the shed to be assembled including material delays and supplier issues.

The ground where I live is basically heavy clay that includes limestone balls.  You can hit this stuff when dry and it’s hard like concrete, when wet your tools bounce like they are on a trampoline.  It’s really tough to dig.  There were 8 holes required dug to a depth of 450mm, the poor builders are on a fixed price contract and required a full day just to dig the holes.

The back wall went up on the beginning of the second day.

It was about now that I realised a 3m high shed (at the eve’s) was large.  It doesn’t sound very big off the drawings, but when you stand in front of that wall of steel it hits you.  By the end of the second day we had two walls up.

Most of the second day, all of the morning in fact, was lost due to the shed manufacturer supplying the wrong columns, they were too short.  I’m glad it wasn’t me that had to unravel that mess.

So there’s all of the walls up just leaving the roof to complete maybe half a days work. The PA door can’t be fitted until the concrete is done, I’m changing the door to swing inwards which will require a bit of skull duggery to get right.

The shed dimensions are 7.2m long, 5.4m wide and 3m at the eve’s, can’t wait to have 39m^2 of additional storage space.

Anyway now on to the concrete

Shed Project – Retaining Wall

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In late October last year I finally decided to pull the trigger on a new shed, every man needs a good shed.

So down to the local shed builders and select one off the plan, then send the plans to council and wait, and wait, and wait.  That has to be the worst part.  Thankfully the Council got the job done inside two months and approval granted.  Being close to Christmas meant the silly season festivities also put much on hold.  Oh well that gives me time to perhaps build a new retaining wall.

So grab a few mates, throw on a barbie, find the sledge hammers and lets get busy getting that wall down.

One thing we did learn is that 65 year old hand mixed concrete is rather hard.  This required a much larger hammer.  A big thanks to Peter VK5KX for bringing the beast !

 

At the end of two full weekends we had finally finished the demolition and it was time to start building.  Yaaay !

Concrete retaining walls are easy to build, just cement in steel posts to the right depth and spacing, then load with concrete blocks.   This wall was simply adjusted in height to slope with the existing land profile.  Make sure you don’t hurt yourself loading the blocks, they are heavy !   Then it’s just a matter of getting in the bobcat to clean up the site remove any vegetation and rubbish ready for installation.

I’m kind of glad that the shed was delayed over Christmas a bit since the site prep took a little over 6 weeks to complete.  A big thanks to all of my fellow Radio Club members and friends that came to assist.

Ok now for the shed.

Cellular Modem & GPS

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Well it turns out that the HP un2420 cellular modem has an inbuilt GPS that can be turned on and off..   So a bit more google foo and I found all that was necessary is to echo a command into the third enumerated serial port like so;

#$ echo "\$GPS_START" > /dev/ttyUSB2

Then we can just point our favorite GPS monitor program at /dev/ttyUSB2 and we should see NMEA data.  I used gpsmon to test mine.  I was amazed to watch this working on my bench inside the shack.

Now my Wenet ground station can easily go portable with Cellular data and GPS position information and no USB 3G dongles required.

HP Cellular Modem for HP 5320m

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After pulling the bottom cover off my second-hand HP Probook 5320m a couple of times I was pleased to discover a PCI-E slot for a HP un2420 mobile broadband modem.  It appears that the Cellular antennas are already built within the lid (or screen) of the laptop.   A light bit of reading also suggested that these modules were capable of decoding GPS signals too.

I just had to try one.

So for the princely sum of $35 I procured a HP un2420 Gobi 2000 module from a local eBay seller.  There are suppliers on eBay that are selling these HP Gobi 2000 modems out of China for $11, which is an absolute bargain. YMMV.  I didn’t want to wait until after Christmas to try one so I purchased one at the higher price.

Now of course I want this to work in my shiny new Ubuntu 16.04 LTS laptop.  Oh well I’ve always welcomed a challenge.   I’ll detail the steps I took to get to a working solution.

First we should check we can see the module;

#$ lsusb
Bus 002 Device 002: ID 8087:0020 Intel Corp. Integrated Rate Matching Hub
Bus 002 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 001 Device 004: ID 05c8:0403 Cheng Uei Precision Industry Co., Ltd Webcam
Bus 001 Device 003: ID 03f0:241d Hewlett-Packard Gobi 2000 Wireless Modem
Bus 001 Device 002: ID 8087:0020 Intel Corp. Integrated Rate Matching Hub
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub

I’ve highlight what we’re looking for (in blue) which is the “HP Gobi 2000 wireless modem”.  You can tell that this device is currently un-programmed as the product ID is “241d” and changes to “251d” once the firmware is loaded.   You also need to check that /dev/ttyUSB0 exists and that your user that starts the 3G cellular modem is in group dialout.  This isn’t necessary right now but does simplifies things later.

Now you’re going to require a Microsoft Windows machine, sorry there is no other easy way around this.  Some have managed to pull apart MSI files in wine, I didn’t get that lucky.  The Qualcomm Gobi modems down load the firmware into the modem at power on, once the firmware has been download the modems will work.   I was lucky to have the same laptop with Windows 10 installed, so I simply installed the driver on this second machine and then stole the files I needed on a USB stick.  I had to install the un2420 module in the Windows machine to get the drivers to load.

From within the Windows driver there are two directories from which we need three files;

  • ….\Qualcomm\Images\HP\UMTS\amss.mbn
  • ….\Qualcomm\Images\HP\UMTS\apps.mbn
  • ….\Qualcomm\Images\HP\6\uqcn.mbn

You’ll need to work out where the drivers get placed depending on your version of windows, it will be installed in the program directories there somewhere.  I found them in the Program Files (x86) directory on Windows 10.   The files above are what you require for a Generic UMTS modem (6) that is not vendor network specific or locked.  This worked nicely for my unlocked module and Telstra pre-paid SIM. YMMV.

Now once you have these files on a USB stick you can start work on the Linux machine.

#$ sudo apt-get install gobi-loader

This will get the udev helper we need to load the firmware into the modem.  Once this is installed copy the files from the windows machine into this directory, watching file permissions of course;

#$ sudo cp /mnt/usbstick/* /lib/firmware/gobi

As mentioned we want all three “mbn” files above in that directory.  Now you might like to check that the udev rules for QDL modems are correct in the following file;

#$ less /lib/udev/rules.d/77-mm-qdl-device-blacklist.rules

Your looking to check that the following two lines exist;

#HP un2420 Gobi QDL Device
ATTRS{idVendor}=="03f0", ATTRS{idProduct}=='241d", \ ENV{ID_MM_DEVICE_IGNORE}="1"

These lines will prevent ModemManager in Ubuntu from trying to take control of this device at boot up before the udev helper gobi_loader gets a change to load the firmware.   Now if all is going well reboot the machine and then check the following in a terminal;

#$ lsusb
Bus 002 Device 002: ID 8087:0020 Intel Corp. Integrated Rate Matching Hub
Bus 002 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 001 Device 004: ID 05c8:0403 Cheng Uei Precision Industry Co., Ltd Webcam
Bus 001 Device 003: ID 03f0:251d Hewlett-Packard Gobi 2000 Wireless Modem
Bus 001 Device 002: ID 8087:0020 Intel Corp. Integrated Rate Matching Hub
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub

You should notice that the product ID has changed from 241d to 251d, meaning that firmware is now loaded in the 3G modem.  I tried not rebooting this machine which turned out to be a mistake.  ModemManager is a pernickety piece of software that won’t do anything unless everything is 100% right.  I wasted a number of hours chasing my tail trying to get services shutdown and restarting stuff.

You should also see that there are now three tty USB devices attached to the system;

#$ ls /dev/ttyUSB*
/dev/ttyUSB0 /dev/ttyUSB1 /dev/ttyUSB2

If you don’t see these three devices then there is something wrong.  I’d suggest you start with dmesg and searching your way through syslog to find out why what’s gone wrong.  It can take a while.  When you do get things right about 13-15 seconds after the kernel loads you should see the firmware loaded into the modem and the additional USB serial ports being created.   If the firmware doesn’t load you will find error messages in syslog.

Now you should be able to configure the NetworkManager to actually use the Modem.  I simply went into NetworkManager -> Edit Connections and created a mobile broadband connection from scratch.   The APN we want to use for Telstra is “telstra.internet” and the rest is pretty much a vanilla install.

Once you’ve got the connection, done you should be able to connect to the internet via the cellular modem.

Oh and don’t forget to plug your SIM into the slot in the battery case.   Now you can sit back and enjoy Cellular Mobile data without any external USB dongle to snap off, or get left behind.

Yay !

SSDV equals Laptop Mania

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I’ve been recently hunting for a laptop or computer I can run Linux on to allow me to participate in a Slow Scan Digital Video SSDV experiment from a High Altitude Balloon.   Some of our AREG club members are developing a high speed FSK modem that is capable of 100kbits or more on 70cm.  Over this high speed link digital images are sent throughout the high altitude balloon flight, the combination of SSDV and high speed FSK has been named Wenet.  These SSDV images are reconstructed on a server in the UK from multiple ground stations streaming their data (click).   Recent testing has shown that the on-air performance is less than 1dB away from the theoretical maximum, David has written an excellent article on it here (click).  However if I wanted to join the fun I need something to run Linux on.. Hmm what to buy.

So when one of my AREG club members emailed our club mailing list with details of a local computer recycling shop selling refurbished HP Probook 5320m’s for $100.  How could we go wrong.

The Intel i3-370M processor is relatively old and puts this machine at the low end of the performance curve, but with 4GB or RAM and 250GB 7200rpm drives these laptops still offered good performance and excellent bang for buck.

So once I’d visited the computer recycler and purchased a laptop it was installed with Ubuntu 16.04 LTS and the usual upgrades and massaging applied to make it all work.  This was the first time I’d experimented with Debian Jessie but the end result was a working machine.   By working I mean working, so the Wifi, Bluetooth, battery monitor, webcam, touch pad, buttons, keyboard, USB, Display port all just simply worked.  There is something to be said for sticking with non-bleeding edge hardware.

The Wenet installation is relatively painless if you’ve ever compiled things from source.  This was then married with a RTL-SDR and 70cm preamp.   The big test was then Horus Flight 39 in which said laptop and system were put through there paces by my eldest son Daniel, you can follow the write up here (click).   The entire team in the tracking car were amazed to watch the pictures “live” from the balloon on this flight.  I had to concentrate on the road a lot of the time with people making oooh and ahhh sounds around me.

I’m told the processor was loaded about 30% the majority of the time and the machine remain responsive under load.   This will certainly do very nicely for this experiment going forward.  What is also strange is I now find myself sitting on the sofa of a night time using this laptop in anger surfing the web.  It boots fast and is great for “looking things up”, so far it’s run for 5-6 days without needed to be charged.

Now to work out what else we can do with it !

Posted in HAB

The alternator strikes back !

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bxd1312n-02I don’t know why but Hilux Alternators don’t seem to last long.  I’ve now had four Asian made OEM aftermarket alternators fitted to my Hilux over the past 7-8 years.  They last just longer than the statutory warranty period and then fail.

I replaced the last alternator in Jan 2015 and here we are 18 months later (~36,000km) and the OEM alternator I used has blown an internal seal within the vaccum pump which has allowed engine oil to penetrate the housing.  Not to mention drop oil on the dump pipe and ground, I’ve spent way too much to have this engine leaking oil.

I did in fact notice last week that the vaccum assisted power brakes were a little “weak” in the mornings, made a mental note to investigate on the weekend.  Friday night after a longer than usual drive to St Kilda in Adeliade, well I could smell burnt oil and a new “awful” whining sound emanating from under the bonnet.  Damn there goes another one.

Anyway after a serious amount of google foo looking for any replacement alternator that wasn’t from an Asian OEM supplier I settled on a a Bosch replacement.  Turns out that they are infact made in Asia, but I trust that German quality control will give me a better outcome.

I purchased the bosch unit from a local auto supplier that was having a 20% off sale on the day, which in fact pushed the price below trade.   For the later model Hilux’s in the LN106 series where the vac pump is on the front of the alternator and not the rear, it’s hard to find the part number of the unit with the pump on the front.  So if your looking for one it’s the BXD1312, it took the young assistant that served me two goes to get the right unit we resorted to looking on the physical shelf when the computer system was leading us a stray.

There She Goes !

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Well there she goes the old Hilux has finally rolled over 400000 km’s. I’m not sure why but I’ve been collecting these images since I first purchased her with 43,000 kms on the clock.  It seems that these memorable moments always occur either during or just before I go on a major trip i.e.

  • 100,000 kms On the way back from Beachport/Robe (~800 km round trip)
  • 200,000 kms Adelaide to Sydney via Townsville Trip (~12,200 km trip)
  • 300,000 kms Horus 25/26 Balloon Hunt Mildura (1100 km trip)
  • 400,000 kms Portrush road day before Warraweena Trip (1400 kms)

As usual the T-Belt light came up and was quickly reset since the timing belt was changed during the recent engine rebuild.  It will be interesting to see where we roll over 500,000 km’s in a few years time.

Waverley Amateur Radio Society Powerpole Kit

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W.A.R.S Powerpole Kit

A few members of the AREG got together and purchased a group buy of the Waverley Amateur Radio Society Powerpole Kits to build.

I got mine for my contesting setup since they were cheap and cheerful and I could screw my West Mountain Radio RigRunner under my bench.

Construction of the units is not difficult and the instructions are nice and clear.   A job well done by the WARS that is for certain.

However with power distribution you’re always wondering just how much current can you run through them without damage.

I’m luck enough to have access to the nice toys at work for testing of power supplies.   So I ran up our grunty PSU on the input, connected the load to output 6 (furthest from input) and ran up a conservative 25A continuous as the worst case and waited.   The majority of my “contesting” radios will reach 25A peak with an average far lower than 25A, should be good enough.   It does mean I’m not too worried if two radios were used at the same time however.

Using a thermographic camera I was then able to go looking for what is “getting hot” a sure sign of something under stress.  After 10 minutes of “thrashing” the temperature stabilised and I was able to capture the following two images.

ir_1367ir_1368

The first image showed me that there was something getting hot at this power level (345W) my initial thoughts were the copper traces or a dodgy solder joint.  It turns out it’s the fuse if you look at the second image.

These automotive blade fuses run stonking hot at high current levels, far hotter than I’d ever considered before in the past.   Keep in mind that these are 30A fuses and were 15% within their rating at the time. This stands to reason when you consider that the fusing capability of such an element is a function of the current (I) squared and time (t).  So the higher the current the shorter the fusing time, the squared term ensures that the relationship is not linear.  The heat from the fuse was far greater than the heat from the traces.

Anyway my rough tests and thermographic images certainly tell me that a properly constructed WARS powerpole kit will happily run within it’s designed ratings of 30A continuous on the input.   Time to order one or two more for the junk box me thinks !

Cruise Control

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Just after I’d finished replacing the engine my windscreen wipers decided to call it day.  Driving along a flat piece of road just before dark the wipers and washers decided to come on of their own accord with the switch in the OFF position.

It seems that my intermittent wiper control function had failed short circuit there somewhere, wasn’t hard to yank the connectors off the washer and wipers and carry on back home.  Searching for a new windscreen wiper control module saw my parents standing in a wrecker close to their home fetching me some parts (thanks Mum & Dad!).  Unbeknown to them the wiper and headlight stalk was being pulled out of a petrol automatic 4Runner, which is very close but not quite the same as a Hilux.

Anyway my parents dropped off the newly acquired part and I got my first look at it.  There was one very obvious difference and that was the clock work spring and indicator cancelling mechanisms were different.

Looking closely it took me all of 10 seconds to realise that the clock work spring in this wiper mechanism had switches in the steering wheel, the question was what type; cruise control or radio?

Well that saw my parents back at the Wrecker the following morning to retrieve the attached steering wheel.   I got an excited telephone call to tell me it was the cruise control switches.   Yippee !!!  Had we waited 10 minutes longer we’d have missed out, the second customer through the door of the wrecker that day was after the same steering wheel; Mine, all mine, Shooo !!!

The steering wheel on closer inspection had a loose grip which is unfortunately defect-able (but common) here in South Australia.  So a visit to a local motor trimmer saw the steering wheel repaired.  The best part is the cost of paying someone to repair the wheel was the same as buying a kit to do it myself off eBay; the difference is that I paid someone who knew what they were doing to effect the repair !

The steering wheel and wiper assemblies on 4Runner’s and Hilux’s are readily interchangeable so with a bit of disassembly, un-plugging, re-plugging and re-assembly my Hilux now sports cruise control switches in the steering wheel.  You wouldn’t know it didn’t come without them,.

Searching the net I’ve found a number of after market cruise control systems that are easy to retro-fit to many different vehicles.  All that is required is a speed sensor, clutch switch, tap the brake circuit, plug things together and mount some switches close to the steering wheel.

I’ve got I’ve got a feeling that I can pull a brake switch assembly out of another Hilux and mount this to the clutch pedal for not many $$$.   That would just leave me with mounting a vacuum actuator (some are servo based) and wiring the thing together.   I can see another project in the wind..  At least I have the “factory” steering wheel switches already sorted.