[SinclairZX81]

I think I just won a competition I didn't want to enter and became the first to fry a SSD sensor chip

Along the way I can confirm that I was able to take the SSD circuitry from one of the hideous porsche boxters in the 'lane change challenge' (or is that 'lame name challenge?') and put it in a Scalextric Mini.

Removing the controller chip was the trickiest part as it is glued onto the boxter mount. I ended up breaking the mounts to get it out. The sensor chip was easier. Its held in place by melted plastic blobs. I just scratched at them with a tiny flat bladed screwdriver until they broke away. Then I unsoldered all the wires noting which side red and black went.

I mounted the tiny sensor board in the Mini's button magnet hole by rotating it 90º from its orientation in the Porsche. A dab of CA on the magnet mount rim was all that was needed.

Unfortunately this placed it right between the terminals of metal strips that run from the guide where I soldered the wires from the controller board. This would later prove to be my undoing. I soldered the wires from the board to the mount points on the motor and was ready to test...

.. and it worked!

At this point I was just testing it with the chassis but around it went changing lanes like a trooper. And then the lights flickered and dimmed and it stopped. I pushed it to the track and it started again. It stopped again. I fettled with the braids. It was off again! It stopped again.

I figured it was a contact problem so I had another look and realised that one of the metal strips that run from the guide wasn't contacting the braid securely, so I pushed it back straight then went back to the track.

BANG! Smell of burning circuitry. Uh-oh. Pull trigger. It goes! The lights stay on. It doesn't stop... and it doesn't change lane anymore. Bugger!

Seems when I pushed the metal thing back straight I also pushed another (bare) wire against the sensor board and it made contact. Oops.

For a while I had a digital Mini. Sort of. I tried fitting the car body just to watch it go round and quickly realised that the controller circuit wouldn't clear the interior. The only place I could see it fitting would be right by the motor which would require longer wires. I took out the interior and took it round a few laps anyway. Hope they get the retro-fit chips in soon.

 

[SWoRd]

Bummer

QUOTE (SinclairZX81 @ 28 Nov 2004, 08:41)I think I just won a competition I didn't want to enter and became the first to fry a SSD sensor chip

<snip>
Hope they get the retro-fit chips in soon.My slot car pusher tells me that they are available in about one week or so

//Søren

 

[Doug]

Ok Sinclair, what have you learned from this and what can you tell us to prevent it happening again

 

[SWoRd]

Heat shrinking tube and isolating tape are pretty good inventions ... just my $0.02

 

[SinclairZX81]

QUOTE (Nuro @ 28 Nov 2004, 11:26)Ok Sinclair, what have you learned from this and what can you tell us to prevent it happening again

<{POST_SNAPBACK}>

I have learnt that there is very little space inside a Scalextric Mini for the SSD controller board.

I have learnt that converting all four of my Minis will be a bit of a pain but within the realm of my rudimentary electrical skills (see next point

)

I have learnt, as SWoRd notes, that I should have covered the the back of the SSD sensor board with a little bit of insulating tape!

I have learnt that I will need to wire things differently next time to let the board sit right at the back near the motor. I think I'll have to leave the original wires that run back from the spade terminals to the motor, an either snip them and connect the controller board wires to them or de-solder the original wires from the controller board and solder the Mini wires to the board (although I wanted to avoid this).

I have learnt that the lights are not connected through the controller board and therfore stay on at a constant brightness. This is good in that they don't go out when you stop or change intensity as you accelerate/deccelerate, but bad in that it means no braking effects etc. At least not for conversions. ( Note that the SCX lights are controlled by the chip )

I have learnt that the design of the new guide blade system introduced by Scalextric in the Skoda Fabia was led by the needs of SSD.

I have learnt that the button magnet hole is a suitable place to mount the SSD sensor.

So I learnt a lot of things but I also have a question (out of curiosity): What is the purpose of the small brown capacitor that is connected at the motor and now also at the braid?

 

[GRAH1]

QUOTE What is the purpose of the small brown capacitor

Spark surpression .Leave it in place it remvoval may cause TV interference or possibly even interfere with the operation of the digital IC

 

[SinclairZX81]

QUOTE (GRAH1 @ 28 Nov 2004, 20:44)QUOTE What is the purpose of the small brown capacitor

Spark surpression .Leave it in place it remvoval may cause TV interference or possibly even interfere with the operation of the digital IC
<{POST_SNAPBACK}>


Thanks. I am curious as to why the one at the motor is still needed then. I left them both in by the way - don't alter what you don't understand!

Oh and another question: Anyone know if the SSD sensor board only will be offered as spare?

 

[Fergy]

QUOTE I am curious as to why the one at the motor is still needed then.

I'm only guessing but probably to prevent noise from the motor affecting the decoder. With the decoder between pickups and motor, it will be susceptible to noise from both sides.

 

[SinclairZX81]

QUOTE (SinclairZX81 @ 28 Nov 2004, 20:05)QUOTE (Nuro @ 28 Nov 2004, 11:26)Ok Sinclair, what have you learned from this and what can you tell us to prevent it happening again

<{POST_SNAPBACK}>
I have learnt that I will need to wire things differently next time to let the board sit right at the back near the motor.
<{POST_SNAPBACK}>


**UPDATE***

There is NO room inside a Scalextric Mini for the SSD controller board! Not without hacking the interior somehow. Not that I can see anyway.

I had to have something to drive other than the bloody Boxter though so I turned to my new Skodia Fabia Works 2003 (as reviewed by Nuro!) which has the mount points for digital and the new guide blade system.

Well it was still a lot of faffing... the sensor hole in the Skoda needed enlarging and the wires from the Boxter's SSD controller board were too short to reach the side mounted motor. I spliced them to the existing wires rather than risk my soldering on the board

Space was still tight. In fact I had to amputate the driver an co-driver's legs!

( I was disconcerted to discover that beneath the green suits, the plastic is flesh coloured. )

But it worked! I shifted the magnet up front too and soon was managing some nice power slide lane changes as I atempted to beat my own times in rally mode. What a relief after the fast but ugly Boxters!

One disapointment. The Skoda's lighing is wired up differently to the Mini, with the lighting wires all running back to the motor. This means that the lights still extinguish when the car stops. Should be easy to fix but I had had enough of fiddling inside slot cars by then.

Oh and one more thing - there's way too many wires and circuits inside the modern slot car! I had to improvise cable management (sticky tape) to get it all to fit!

 

[astro]

sorry to hear about the fried sensor

Have you talked to scalextric about it? They might be nice, especially as their press implies that the chips are interchangeable with other cars, which is what you tried to do?

regarding lights - front lights could be wirded to the guide, but if you have an analogue overdrive kit, the brake lights can be wired to the motor to give working brake lights! Be better if there is chip controlled lights to come in the future though...

 

[Swissracer]

Scalextric are bringing out two sizes of board, the smaller will be fine for the minis I am sure.

 

[SinclairZX81]

QUOTE (astro @ 29 Nov 2004, 12:26)sorry to hear about the fried sensor

<{POST_SNAPBACK}>

Me too!

QUOTE Have you talked to scalextric about it? They might be nice, especially as their press implies that the chips are interchangeable with other cars, which is what you tried to do?

Mmmm... I don't think they mean for consumers to rip the circuits out of one car and put them into another. They are firmly affixed with CA and melted plastic. But perhaps I will give it a try... or I could go back to the store and give them an "I was just driving along" story...

QUOTE regarding lights - front lights could be wirded to the guide, but if you have an analogue overdrive kit, the brake lights can be wired to the motor to give working brake lights! Be better if there is chip controlled lights to come in the future though...

The lights are the original Scaley ones. I will probably wire them to the guide terminals.

Yeah, chip controlled brake lights would be cool... and how about turn signals for lane changes

 

[Wankel Ickx]

I've learnt that my first guess with this was right, upgrading (misnomer) to digital ain't going to be a walk in the park. I mean, you guys have an idea about what your talking about...me, I've no idea about squat.

 

[Xlot]

No I didn't (fry a decoder), yet - but that's only because I decided to test my "new and improved" Rev.F guide pod in analog mode

I foolishly left bare two wires temporarily twisted together, and of course they had to touch the "other" rail - this disappearing as soon as I lifted the car, so it looked like a broken circuit instead of a short ! - so far, the day's casualties are a wall wart, a cheap multitester in the ensuing panic, and four hours of work

Therefore, digital pioneers beware : Murphy's law is lurking out there, and no doubt the road to progress will be paved with charred PCB

Beppe

 

[SWoRd]

Hi Beppe
QUOTE (Xlot @ 16 Dec 2004, 16:42)Therefore, digital pioneers beware : Murphy's law is lurking out there, and no doubt the road to progress will be paved with charred PCBI'm crossing my fingers, that the 36 car controller PCB's I just got, will last long enough for me to get at least one working car out of it.

Søren