Does anyone here understand this?

[TOOLS1]

This is a link to a homemade coil tester I found on the KZ Rider forum. I don't understand all the symbols, but would like to make one. Can anyone here explain it in lay-mans terms?
http://www.kzrider.com/forum/21-tools/561376-true-coil-tester

TOOLS

[shinyribs]

I do. But I'm not telling. :p



Will explain as best I can later. On the phone now so.....

The open gaps represent normally open relal contacts.

A triangle against a line is a diode. Direction of flow represented by direction of the triangle.

Wavy lines are coils /transformers.  Depends on the components being used.

[TOOLS1]

So!!!! What components are needed to build it, and how do they go together?
TOOLS

[sgtslag]

The 555 Timer Chip (pin out link), is a square-wave generator; in this setup, it outputs a single polarity (DC) square wave.  Pins 2, 6, and 7, all control the frequency, and the pulse width modulation -- how long the voltage is positive (on), or off (zero volts), which is known as duty cycle.

Pin 3 is the output of the chip, which drives the G connector on the HEI Module (link to sample), which pumps the current through the primary coil on the spark coil (the 555 Timer is a low current device, so it provides the control signal for the high amperage HEI Module):  the primary takes low voltage/high current, and transforms it into high voltage/low amperage, which causes a spark to jump the gap on the plug (the power remains the same:  Power/in = Power/out = Voltage x Current; the coil, a transformer, trades one quality up, while lowering the other quality, but power remains the same, due to conservation of energy -- there are minor losses due to heat).

Diode D1 makes sure that only positive voltage is applied to the Timer chip, IC1, which prevents it from being damaged.  Anything marked Electrolytic (Ca, C1), are polarity sensitive -- if you connect the Positive Lead (+) to the Ground/Negative pole of the battery, they will burn up, quickly.  Be careful when wiring them.  They are capacitors, which are used to filter AC ripple out of the power supplied to the Chip (C1), which can damage/interfere with IC1's operation.  Capacitor Ca provides timing (RC/Resistor-Capacitor time constant), it determines the timing of the square-wave output; the combination of R1 and VR1, determine the Resistor value of the RC time constant.  Diode D2 helps supply current to charge Ca, which plays a role in the timing.  The control, VR1, is like a volume control on a stereo:  it is a variable resistor; R1 is used to create a minimum resistance for the RC time constant, as VR1 can go down to zero resistance, so Ra limits this to a minimum value.

I would assume that you connect the coil under test, to a spark plug.  If it has no plug as a load, you will burn up the coil.  The HEI Module notes that its heat sink (metal outside casing, possibly with cooling fins, similar in appearance to the fins on the OEM Rectifier/Regulator's heatsink) must be connected to chassis ground/battery's negative terminal, or it may be damaged.

I would recommend finding someone trained in electronics to build it for you.  The components are not terribly expensive, but if you are not careful, you could destroy the HEI Module, which is expensive.  Cheers!

[TOOLS1]

Sarg I said "Lay-mans terms." I don't give a hoot how it all works. I just to know what is needed, and how to assemble it.
TOOLS

[shinyribs]

Sarge explained it pretty basic,actually. I used to get HEI modules from Advance for about $30. Looks like they've gone up.


Here's a pretty good deal on one. Allstar is a company we deal with alot at the shop. They are just your standard warehouse that buys huge bulks of items on the cheap on blows them out cheap. Never had any issues with their products.Most of it's brand name stuff repackaged in plain brown wrappers.  It's the same 4 pin module the diagram calls for.

BTW,the 4 pin modules are the pre-emission units that do not have the internal advance retard mechanism.

http://compare.ebay.com/like/150775514045?var=lv<yp=AllFixedPriceItemTypes&var=sbar

[shinyribs]

D1 & D2- Diodes. The numbers 1&2 just denotes their position in the diagram. Didoes are electrical ''check valves'',like Sarge said. The orientation of a diode is extremely important for obvious reasons.

R1- Resistor

VR1- Variable resistor. Which is a rheostat or a potentiometer(sp?)

Ca & C1- Capacitor. ''uf'' is shorthand for "microfarads",which is the value a capacitor is rated at. 100uf is 100 microfarads.

IC1- Sarge got this one

HEI- Long live The General!!!!

[TOOLS1]

I see how this is going to be. Won't answer your phone. So, I just go into Radio Shack and ask for capacitors, and diodes?
TOOLS

[shinyribs]

oops. Sorry bud. Didn't realize that was you.


If radio shack doesn't have the components, in the rated values spelled out in the legend, than ebay will I'm sure.

My local radio shack used to be awesome,but now its just cell phone store .


I may have a 4 pic module I can send you. I'll check tomorrow when I get in and call you on the new phone number i was not aware of!


As far as the heat sink on the HEI module, they used the distributor housing as the sink. In normal use,you would smear this wierd,supplied greases that came with the module. It helped to conduct heat away from the module and into the distributor. With no distributor I'm not sure how you would dissipate the heat,BUT,since it's just a quick test to see if the plug will go zap! I don't think it would create enough heat to affect it. You could always mount it to another heat sink if some type. Maybe an old r&r housing, a scrap piece of ally with slits cut in it(faux radiator) or even just put a muffin fan on it if you were really worried about it. But i doubt it would even be an issue.

[sgtslag]

Sorry, Tools, but I did answer your main point:  find someone knowledgeable in electronics to put it together for you.  The easiest way to build this circuit would be to breadboard it.  Breadboarding requires a bit of explanation as to how it works, and that is not possible in this forum.  Explaining how to translate a schematic diagram into wiring, is also not easy on a forum.  That is why I suggest finding an electronics hobbyist/student to build it for you -- it's much more do-able.

You are a highly talented mechanic and fabricator.  You have excellent skills with which to barter.  Your biggest challenge will be to find someone local who can do it for you, in trade.  You can advertise on CL, you could visit your local Radio Shack store and ask for the name of a hobbyist who could assist you.

Otherwise, you will need to learn some basic electronics, wiring of simple circuit boards, and/or breadboards.  If Radio Shack does not have the components on hand, then it is all mail-order, and waiting.

Shiny is correct:  the HEI Module won't be running long enough to heat up, and burn out (for testing, you should only need to run it for a few seconds -- longer, and the HEI Module will heat up and burn out...).  No heatsink will be necessary.

Shiny, the 'wonder grease' is thermal grease, it transfers heat between the electronic device, and the heatsink, allowing the heat to be carried away, without damaging the electronics device.  Thermal grease is used on bikes, but only on heavy current devices (Rectifier/Regulators, and alternators), beneath their heatsinks.  It is rare, indeed, that any M/C Technician would ever need to mess with it, though.  Cheers!

[TOOLS1]

Maybe I am asking the question wrong. How do I know what parts to buy? Do I just take the list on the diagram into Radio Shack? Will they know how to translate the values into the correct parts? As for assembling it, that is not a problem. I just need to know what parts to get.
TOOLS

[sgtslag]

Yes.  Radio Shack staff will be able to put together the parts from the list, if they have them in stock.  My local Shack store still carried some components, but that was a few years ago.  The components are very common, and not terribly expensive.  Good luck!