A puzzle

There is one mechanical design flaw with Solar Ride.

The ball can and will get stuck in the playfield, up near the shooter exit.  There's a gate back to the shooter lane with a spring-loaded switch to award 500 points when the ball passes through.  However, sometimes the ball will get caught by the wire gate instead of rolling into the playfield.

I've dreamed up an electronic / electro-mechanical solution:

"If the switch is on for more than a few seconds, activate a solenoid that changes the spring tension, forcing the ball back into the playfield."

It's so simple!  Just one sentence!

However, after some cursory research, I have discovered that delay circuitry is far from simple.  Do I use a timer IC like the NE555 to introduce a delay?  What about an op-amp and a capacitor, can I get a few seconds out of that?

I want to make this component as simple as possible, but am so far unable to come up with anything that doesn't use a timer device.

UPDATE: There ended up being a much simpler fix for this problem.  The upper mounting hole for the wire gate is fairly large and there's a lot of play.  When the ball was getting stuck, I saw that the return spring for the wire gate was rubbing up on the edge of the through hole in the playfield - changing the return force and not letting the wire bail push the ball through.

Loosening the mounting screw to move the upper post away from the binding edge reduced the problem quite well, and now it hardly ever gets stuck.

Futaba Display fixed!

Tonight I replaced the zener diode on the power supply for Solar Ride.

It is a pain to work on the power supply board - the main power transistor is soldered on through the chassis, so you have to desolder it before you can remove the board from its carrier.  All things considered, though, it went fairly smoothly.

A new RottenDog power supply would set us back $100 or more.  This fix cost $12 - and I got lots of spares, if it happens again.

But it works!  The displays no longer share numbers.  Now, I have to sort out the high scores - but for that I will probably just get a 3xAA battery holder and get some cheap NiCAD or NiMH batteries to stay in here forever.

Up to Potential

We've had a Gottlieb Solar Ride pinball for a while now, and it has had consistent problems with the displays.  They have ghost numbers - the score on the first player display will appear on the other displays as the numbers increase.

Yesterday I traced it down to a failed zener diode / resistor causing the +8V reference voltage to go away.  From the Futaba web site:

"If the filament potential is lower than the anode and grid cut off voltage, thermionic electrons can reach the anode and cause illumination of the phosphor. The filament bias voltage should be increased to prevent this problem." 

Naturally.

Etch a Sketch

Here's the (revised) circuit board for the Garduino Mini.

I had considered wrapping the whole thing in a ground plane, and trying to limit the amount of etchant that is required, but since this is the first time I've done a circuit board I went simple.

Here's how it turned out:

Das Blinkenlights

After much agonizing I got the Arduino Pro Mini [Clone] programmed.  The key was to choose the correct device from the Arduino programmer.

The current prototype has a bluetooth serial to beam data back, plus collectors for temperature, air and soil humidity and ambient light.

The host server will have a PostGreSQL database that stores the data, and some sort of web interface that draws some charts.

We're be going with chart.js for the charting engine and most likely some sort of PHP -> JSON quick hack to spool out data.

Arduino for Everyone

I got a bunch of Arduino stuff from dx.com (aka dealextreme).  They will be used for a Garduino project, so that we can monitor the soil moisture, light, etc for the vegetable gardens.

Tonight I assembled a temp and light sensor on the proto board.

I need to source a 3.3V voltage regulator to drive the bluetooth module, then these can start moving outside.

Pruning the pear tree

Today I pruned the pear tree!  This is what it looked like this morning:

And now, this afternoon:

Pruning keeps the tree from growing too large, and forces it to make more fruit.  I also took off a few branches that were crossed, and some that would grow too close to the shop.

TR4 Startup 1: Before

I made a short video of the TR4 starting up.

This is a baseline "before" - mostly for the sound.  I need to have the carbs rebuilt / resleeved (note the puff from the backfire on startup), the distributor reworked, and the manifold gaskets replaced again.

I put a second mike down behind the car, which gives the car a better sound but makes me sound very tinny.

Repurposing Electrical Boxes

I picked these up for free, they were discarded from a reno.

(Side note: Old electrical equipment is terrifying.)

I considered using the breaker panel as a sub panel when wiring the shop, but Federal Pacific (aka Federal Pioneer / Stab-Lok) got a bad reputation for making circuit breakers that didn't break when the circuit overloaded.  These boxes will be gutted and used for other projects that don't need to meet any electrical safety codes.

Triumph Fenders Acquired

For reasons I cannot comprehend, a pair of TR4 fenders showed up on a local classifieds website.

 They were expensive, as used car parts go, but ridiculously cheap for a set of decent used fenders.

Looks like they were originally midnight blue.  There's a few dings and creases from age and whatnot, but no bad rust at all.  Should clean up really well.

Triumphant Return

I started this blog to document some of the discoveries and processes related to camera repair.

However, upon reviewing my "bottom line" between buying / repairing / selling cameras and the same for bicycles, there's an order of magnitude of difference.  The smaller margins (buying a $40 camera, selling it for $45) plus the parasitic nature of online sales (eBay, PayPal, and the post office all get a pretty good cut) means this blog is being repurposed.

I also have a sports car!  A 1962 Triumph TR4:

I have had it for fifteen years now.  This year, it is 50 years old.  So, instead of continuing the rolling restoration that has been ongoing and off-going for the intervening fifteen years, this year it's coming off the road to receive some much needed R&R.