Needed some Chromatherapy...

[MarkT]

That involved some new thinking, some stimulation.  Instead of the same-o, just on my time.  So I made up a security circuit for my Dan-Marc, making it into an anti-hijack / theft device.  What I did was wired up a flip-flop latch and hid the momentary (trigger) button, to power the Dan-Marc.  So the Dan-Marc is no longer powered just by turning on the key.  You also have to hit the hidden momentary button.  If I get hijacked, either hitting the kill sw or turning off the key will cut the power to the Dan-Marc.  Now if they ride away, they will be outta gas in about a mile.  Without a clue why it quit.  Meanwhile I've called the cops to say the chrome dragon on the side of the road a mile thataway has a hijacker aboard, go throw him in the hooscow.  Yeah, I made a bypass in case of a failure on the road, and also wired an LED that confirms power to the solenoid.  

No, never been hijacked.  Just needed some Chromatherapy.
Can't help it.  Sometimes the geek just takes over...

[R J]

That sounds like a good deal Mark.

Do you have an electrical schematic for it?

I could probably figure out how to do it, but if ya got one I'd rather follow your foot steps.   

That way I can save what brain waves I have for something else.   

[John Schmidt]

That sounds like a good deal Mark.

Do you have an electrical schematic for it?

I could probably figure out how to do it, but if ya got one I'd rather follow your foot steps.   

That way I can save what brain waves I have for something else.   

Same here RJ, don't want to overwork the gray matter. If a schematic of some sort is available, let us in on it. Can be hand drawn and you don't have to be a Rembrandt. 

[MarkT]

Yeah I did the same thing - checked online to avoid reinventing the wheel.  Didn't mean to imply I invented it, but I did stir the gray matter a little before I fired up the googler. I found 2 ways to do it with relays, 5 with no diodes or 4 with 2.  There's other ways too, that involve fewer relays but add capacitors and other components. I did throw together the parts from a simpler schematic (The "Pulse Toggle Relay" uses 3 relays)  but clearly the author didn't test it, as it has a flaw.

Edit 8/18 - Keep reading; better circuit idea using BonS's latch relay schematic below.




Or you can be smarter and just buy the printed circuit all ready to go - less work, less cost, smaller size, and solid state so it's more reliable.  Board dimensions are 60mmX60mmX30mm so that's small enough - much smaller than a bunch of relays - 2.4" X 2.4" X 1.2"; $24 + $10 shipping.



You can get a right-size abs enclosure from the same place.  There's other choices of course.

http://www.mcmelectronics.com/product/28-5115

Here's the forum these links came from: http://www.the12volt.com/installbay/forum_posts.asp?TID=106633&TPN=1&PN=1

[F6BANGER]

Great idea Mark, where did you put the switch.....LOL

[scoobydoo]

Hey Mark, off the subject, but were you wotking on lights for the v-stacks?

[BonS]

How about doing it as a latching relay design. When power is turned off the relay simply falls out. No, I haven't built the circuit but it should work fine.

[MarkT]

How about doing it as a latching relay design. When power is turned off the relay simply falls out. No, I haven't built the circuit but it should work fine.

Yeah that's simpler.  But it  loses the "flip-flop" toggle function in the product title/description - required in my solution.  I want to be able to toggle the dan-marc off discretely by the hand the hijacker can't see.  IOW, I can have a couple momentary hidden push buttons, even ones that don't look like switches, or ones with negative logic (connect a ground); toggle the relay with the off hand / knee / foot - however I implement it.

[John Schmidt]

How about doing it as a latching relay design. When power is turned off the relay simply falls out. No, I haven't built the circuit but it should work fine.

Bon, that was my first question..."why not use a latching relay?"  Is there any specs available on what parts to use? Here in Winter Park we have a place called Sky Craft(http://www.skycraftsurplus.com/) that was originally a small military suplus shop. Over the years it has grown and is a multimillion dollar business now, dealing worldwide. They have literally thousands of LED's, diodes, transistors of all types and sizes. Takes up one entire corner of the place, as does the section for relays. It's one of those places where you can spend hours just looking. If I can't find what I want in there, I don't need it. It's a great source for good electronic parts of all genre.

They even have something for Steamer!    http://www.skycraftsurplus.com/lightedfemalemannequin.aspx

[BonS]

The relay is the common auto parts store garden variety Bosch type automotive relay. In general these relays aren't weatherproof so install in a location and orientation keeping this in mind.

The diode can be a 1N4001, 1N4002, 1N4003, 1N4004 etc. Reasonable specs are 24 volts peak reverse voltage (PRV) and 1 amp forward current(If).

The switch must be a momentary action, single pole single throw, rated for at least 140 milliamps and should be weatherproof. Weatherproof is usually referred to as IP-54 (dust protected & splash proof) or IP-67 (Dust tight and immersion) rated.

The 12 volt LED with a built in resistor can be purchased at Radio Shack or you can roll your own. If you use a plain LED then you'll need to add a series resistor in the range of 1,200 ohms 1/4 watts.

John, Skycraft is a wonderful place. A guy can get lost for hours in there. It's like a tool store for geeks. Getting exactly what you want can be daunting though as there's little there to guide you.

[MarkT]

Looking at this again, if this is done with a latch per BonS rather than my flip-flop latch, to keep the circuit simple and inexpensive, if the 12v switched aux power is taken off the engine kill switch, then in the event of a hijack, hit the engine kill - right there by your thumb - rather then switching off by key or the flip-flop momentary sw, and the relay output - thus the dan-marc - would be disabled until the hidden pushbutton was pushed again.  Hmmm.  Not a bad idea, the std 4 or 5 pin relay is $5 rather than the $33 (incl shipping) of the flip-flop latch.  Which I've already bought.  Oh well, I'll surely find a use for it.

Now looking at the 98 Valk Standard/Tourer schematic, the Bl/W wire in the 9-pin mini Black connector, with 8 pins populated, in the headlight shell, is the wire that is switched off by the engine kill sw.  Don't know if these wire colors are the same with the I/S. Some other wire colors are different.