Archive for March, 2007

victory gals

Only the most incredible WW2/Aviation art you’ve ever seen.
Gangus’s Victory Gals
And his homepage.

Electronics links

Decent pic tutorials at Spark Fun Electronics
Generic circuits wiki at Open Circuits

“The Aviator” webzine

check it out

SSOH – the saga continues

Well as the saying goes, no plan survives contact with the enemy. In my case, the SSOH worked beautifully right up to the point where I installed it in the pit and tried to trigger it from inside the house. Turns out with the monitors and everything else shielding the receiver, I can’t trigger it with the doorbell board inside the case.
So, what I’ve done for now is to hang the receiver outside the case, and will simply extend the receiver away from the case using the original receiver case and some sort of 4-wire cable (probably CAT5 UTP for consistency).
Bit of a hassle, but it all works fine with the receiver extended into a clear area.

SSOH module ready for liftoff

Well, that was fun. After working beautifully on the breadboard, I had a couple of nasty problems once it was all assembled on the circuitboard. When I powered it on, both lights came on and would only go off when I hit the remote – and would both come on again 5 seconds later! It turned out to be two things: one, a missing track break and two, a missing ground connection to pin 5 on the PIC.
Two hours of debugging (watching Raising Helen with the missus was the other option, so it could have been worse), a couple of minor solders and it was all good.

working. at last.

the board before attachment of the upper deck
ssohfinal_1 (62k image)

the completed assembly
ssohfinal_2 (54k image)

mayday mayday mayday, TJ has grazed his knee and needs a cuddle, abandoning mission
ssohfinal_3 (34k image)

MCSSOH board underway

A couple of hours’ work last night double checking the layout and fitting the major components. The spacers are so that I can fit the doorbell receiver deck above my board. It all fits nicely in the case.

Jeez Louise, it’s so much easier doing this after designing it first. It’s like assembling IKEA, not the usual solder – bugger – desolder – repeat exercise that I used to go through.

just jumpers and track breaks to go
mcssoh_board1 (51k image)


Well the SSOH FAIL warning light works beautifully on the prototyping board. Basically it’s a little PIC16F628 microcontroller that controls both the MASTER CAUTION and SSOH FAIL (Spouse Sense Of Humour Failure) warning lights. It is triggered off a little wireless doorbell circuit – so the missus keeps the little remote button, and can press it from anywhere in the house, which lights up the warning light in the pit.
I hacked the doorbell receiver so that instead of sounding a doorbell gong, I run the AC output to the speaker through a rectifier and NPN transistor which triggers a pin on the PIC when sounding. The PIC simply senses the pin trigger and lights the SSOH FAIL lamp. It remains lit until I press the button to cancel it, which triggers another pin on the PIC and it turns the lamp off.

in action on the prototyping board

Of course, using a microcontroller for such a simple function is a bit of overkill, but I also wanted it to provide the MASTER CAUTION lamp. I’m having some trouble getting the PIC to talk to a PC via the serial port, so the MASTER CAUTION light doesn’t work. Once I’ve ironed the bugs out of it (I’m sure it’s just a stupid error in the firmware or an equally stupid wiring error) I’ll be able to trigger the MASTER CAUTION light from any sim software that supports callbacks. The press-to-cancel on that light will simply be linked via the PlasmaV2 to a keypress.

the circuit
mcssoh_cct01 (27k image)

I’m not going to etch a board for this module, I’m doing it on perfboard. However, as it’s a reasonably complex circuit, I’ve designed the perfboard layout using the PCB software from ExpressPCB. The red lines are the perfboard traces, the yellow X represents where the traces need to be cut, and the green lines represent patch wires.

the PCB layout
mcssoh_layout01 (93k image)

AU Helo Tour leg 7/8

Mildura to Horsham via Buckhurst Station. As I was planning the leg, I realised that it would take me very close to Mt Arapiles; one of the premier rock climbing sites in the world, and the site where I led a grade 19 climb in 1990 (still the hardest climb I’ve ever made).
So, I decided to put in a 15nm diversion to see if it was represented in FS2004. Is certainly was, and looked just as I remembered it. What a buzz!
After a couple of orbits, I headed off for Horsham. I had deliberately not refuelled at YBHS, as it is an unlicensed strip and I was pretty sure AVTUR wouldn’t be available. I was a little concerned about fuel, as I had just over 50% onboard (1300lb) on departure and was burning about 1100lb/hr. But with a few rough calculations on the whizwheel (it’s all coming back!), I was happy that I’d have 500lb or so over Horsham even with the diversion. As it turned out, I had skids on with 300 lb in the bladder. All was well.

Mt Arapiles from the air (click for larger)
{{popup mtarapiles.jpg mtarapiles 800×515}}mtarapiles_t (39k image)

AU Helo Tour Leg 6 – YSWH-YMIA

departing Swan Hill in the cold light of dawn
auht6_01 (37k image)
arrived at Mildura – long shadows in the early morning
auht6_02 (19k image)

AU Helo Tour leg 5

Short hop up to Swan Hill from Echuca at dusk. Lovely.
wop wop
auht5_01 (8k image)

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