New Technology Brings Fiasco

So what the Dickens happened? I report on exciting new technology deployment possibilities and then...not a dicky-bird for months.

Well, it all started in a very promising manner, with the acquisition of a few yards of Electroluminescent Wire (EL Wire in the vernacular) and a sequencer circuit to make them illuminate in patterns.

The first problem was that the EL Wire terminated in one sort of plug and the sequencer expected a different one. This was a trivial operation.

The second was that I had four two yard strands and I needed eight one yard strands, thus I was forced to become adept at terminating EL Wire (and acquire a few bits and bobs that are not part of the casual electrician's toolkit).

This involves cutting away some of the plastic cladding from the metal core wires, teasing out the two hair-fine "corona wires" without breaking them, winding copper tape around the plastic cladding at the cut-off point, soldering the corona wires to the tape, scraping off the phosphor coat on the protruding center wire and soldering the plug wires to the center wire and the tape. I only had to re-do two of them.

Then I discovered there was a design flaw in the sequencer. It could be worked around, but there was an upgraded circuit so I obtained one of them instead. Then I had to solder in so-called "headers" so the sequencer could be reprogrammed using my portable Babbage machine.

The new board could take 12 volts, which would be convenient for a number of reasons but required a new inverter, which had the wrong plugs and so on and so forth.

Eventually everything was sitting on the bench with the right plugs on the right wires. I connected up the various pieces and was rewarded with some rather strange flickerings that then settled down to the sequence I expected. It was a good start and I was just about to disconnect everything and retire to the living room for some reprogramming of the sequencer when there was a fizz and a puff of smoke and that was that for the sequencer.

It turned out one of the wire tracks on the circuit board had melted.

So, I retired in disgust from the laboratory and haven't gone back inside.

New Technology Brings New Ideas

Well, sort of. I have been experimenting with Electro-Luminescent Wire with a view to replacing the rather disappointing lighting effect inside the Neuralizer's barrel shield, currently a steady green light provided by two four-inch cold cathode lamps, with a more dynamic one in keeping with the lightning effect of the Lumin Disc in the Aethero-Galvanic Exciter and the plasma-snake of the central resonator in the Neuralizer itself.

To do this I obtained an EL Wire sequencer which has proved problematical due to a design issue (in the circuit board). There are work arounds available and I'm following them, but they require reprogramming the board and that is a non trivial operation. In the interim I have also ordered the new version of the sequencer and perhaps that might be the best way to go. We'll see.

The El wire offers a rather nice form factor that can be used in many creative ways, and in conjunction with the programmable sequencer offers some really interesting possibilities such as moving patters of light that change over time or upon performing an action - like pulling the trigger or perhaps adjusting the stopcock on the front end.

In the near term, another upgrade has suggested itself, this time to the Aethero-Galvanic exciter. In the previous article I talked about the need for a three volt supply for the Lumin Disc while at the same time a twelve volt supply was needed for the Neuralizer. I spoke of how I solved this using a separate three volt battery connected to a relay.

Well, I've found a nice little three volt power supply that can be driven from a twelve volt DC source, which makes the separate battery unnecessary. Better yet, it makes the battery optional, and opens up the possibility of using a wide range of different batteries, three volt, nine volt, whatever comes to hand. In theory I can even do away with the relay, which will obviate one source of failure. Not sure that I will, though. That is still under review.

But it does mean that I will be able to use the one twelve volt lead acid battery to run everything, and when that loses charge I can swap in a 9V battery to run just the Lumin Disc. Space will be more efficiently used inside the box and options will be widened.

So that's next up on the agenda.

An Interlude with Wiring.

Now the real problem with the Neuralizer is that is gobbles electricity. There was no chance that it would ever be practical to make the power supply a self-contained affair, hence the need for the Aethero-Galvanic Exciter (or in more prosaic terms, the battery box).

But it couldn't be just a box, not for something as optically busy as the Neuraliser. It would have to be a piece of optically-active sculpture in its own right, and I'd seen Lumin Discs incorporated into steampunk handbags before, so when I came across a source of inexpensive three-inch diameter Lumin Discs it was obvious what would be the perfect jazzer-upperer for the Aethero-Galvanic Exciter.

The only fly in Nurse McReady's Surgical Bruise Lotion is that the Neuraliser requires a twelve volt supply, whereas the Lumin Disc requires a three volt supply. I could have built something called a voltage divider, but I'm not electronically astute enough to build much beyond a resistor string and though one can turn such things into voltage dividers they waste energy (already in limited supply) and the voltage across the Lumin Disc would fall off as the general voltage dropped, causing G_d knows what sort of behaviour.

The easiest way to address the issue would be to use the twelve volt battery to power the Neuraliser and a separate three volt battery to power the Lumin Disc. Controlling all this through one switch would require a relay.

A relay, for those who have never seen one, is an electromagnet that throws a switch when the coil is energised. The switch can in fact be several switches, so I would use a low-current consumption twelve volt  relay with two "normally open" switches, one to switch the voltage for the Neuraliser, the other to turn on the Lumin Disc.

The connections are as follows: The battery positive is connected to the 2 amp fuse. The fuse is connected to a Y splitter, one leg connected to the rotary switch that masquerades as the red stop tap on the front of the Aethero-Galvanic Exciter, the other to one side of one of the relay switches. The other side of the relay switch is connected to the power socket in the side of the Aethero-Galvanic Exciter, and the other side of the rotary switch is connected to one of the relay coil connectors. The other relay coil connectors is connected to a Y splitter, one leg of which goes to the negative pole of the twelve volt battery and the other to the socket in the side of the Aethero-Galvanic Exciter.

The Lumin Disc is modified by removing the shield covering the circuitry and lengthening the battery wires. A separate battery holder is obtained, and the positive side of the battery holder is connected to the other relay switch contact. The other side of this switch is connected to the positive terminal of the Lumin Disc. The other terminal of the battery holder is connected to the negative terminal of the Lumin Disc.

NOTE: The Lumin Disc is a polarised device - it is crucial to identify the positive and negative sides of the device and to connect them to the proper terminals of the battery to avoid destruction of the electronics. The Neuraliser electronics are also polarised and proper care must be taken to identify the positive slot in the socket and to wire the positive side of the inverters accordingly.

It is a rule of thumb that we put all switches and fuses in the positive side of the circuit, and a matter of necessity that the fuse goes as near to the battery as possible. The Lumin Disc should also be fused, but since the wires, battery and electronics will be relatively safely housed in the box the danger is much less than with the Neuraliser, where the wires can get caught in scenery, opportunities for short circuits are more numerous and even water could get into the equation if it starts raining.

So what happens when you turn the tap on the Aethero-Galvanic Exciter?

The rotary switch supplies power to the coil of the relay, which throws the two switches, which connects the twelve volt supply to the socket and the three volt supply to the Lumin Disc. I've included a kinematic diagram in an attempt to clarfiy things.

So, if you can see the Lumin Disc effect, there is a connection between the twelve volt battery and the socket and enough juice in that bettery to pull in the relay. I'd really like some sort of voltmeter, but instruments that were dirt cheap in my youth are now impossible to find, and even inexpensive analogue meters are very pricey affairs, especially the ultra-desirable moving coil meters.