The RMC Impulse Drive Buzz Coil This is a multi-spark (buzz spark) ignition coil that can be used on most any engine with a spark plug, from a low rpm single-cylinder antique hit & miss engine, to a higher-speed multi-cylinder engine. The coil produces continuous sparks the entire time the engines ignition points or contacts are closed. It's built from all new components & is completely solid-state (no mechanical relays or points that can corrode & wear out). The RMC Impulse Drive Buzz Coil has a built-in amp that only sends low current (0.05 amp) through the points. This stops arching & sparking & will prolong the life of the engines points. No condenser is needed with the coil & it will work with conventional points or with low current devices such as a Hall sensor or a reed switch. This coil is great for model engines since the ignition points or contact wipe can be built thinner, lighter, smaller & more to scale with the engine. Basically a pin head can be used to trigger the coil. The coil unit is small, clean, compact & easy to hook up. It's also water proof & UV resistant. Since the sparks start to occur when the ignition points or contacts first close there is less problems with point bounce, contact float, etc. The high-speed multiple sparks also provide more heat energy that can ignite a wider range of fuel mixtures. This results in a noticeably smoother running engine that is less touchy on carburetion & fuel settings. Engines that already seem to run good may run even better on this coil. The coil has been through endurance tests & has also been tested on high speed, high compression engines. See test demonstration video below; A 12 volt battery was used to power the coil in the video above. If tamed-down smaller sparks are wanted, lower voltages can be used. Read notes towards bottom of page. Conventional multi-spark (antique Ford) buzz coils usually generate around 200 to 600 sparks per second. The RMC Impulse Drive Coil generates around 3,700 to 4,600 sparks per second. The difference can be seen in the charts below; The RMC Impulse Drive Coil is tough, it was made with good materials with internal components over-rated by almost 50% or more, BUT a coil should never be tested by seeing how far of a gap the spark will jump. In open air it can jump over a 1" gap but the larger the gap, the higher the voltage needs to be to jump it. This will eventually lead to an insulation breakdown & shorting. Because of this, always make sure the spark plug wire is on the spark plug or has a grounded gap to jump & it’s not recommended to jump gaps over a 1/2" with the ignition coil. =Random Notes= The BAD: -The coil should not be left on with the points closed continuously for long periods of time (over a minute) with higher voltages (anything over 9 volt). If the coil ever gets uncomfortably warm to touch, let it sit to cool. -If using the coil on 12 volt to run a multi-cylinder engine where the coil is on almost continuously, it may need the voltage dropped down to 9 volt to prevent the coil from over-heating. -A battery does not come with the coil. Normal household alkaline batteries will work if wired in parallel to safely provide about 2A but a higher amp gel cell type battery is preferred. -The ignition test engine shown in a few of the pics above does not come with the coil. -This coil is not a direct replacement for a Ford Model T buzz coil, see following notes. -The coil is polarity sensitive & is not tolerant of reverse voltages (accidently hooking its power wires on the battery backwards). The red & black (battery positive & negative) wires are well labeled but if there is still a concern about accidently hooking the coil up to the power supply backwards, a one-way, low voltage drop diode can be supplied with the coil for protection against this. -The power supply running the coil must be fairly steady DC (like from a battery). Running coil directly off a battery charger (from AC power) might not work. Running the coil directly off a DC mag, dyno or generator might not work. -This is a positive ground coil meaning that the engine frame will be grounded to battery positive. =Random Notes= The GOOD: -The coil can be used on most any spark ignition engine, from a low rpm single-cylinder antique hit & miss engine, to a higher-speed multi-cylinder engines. -The coil has a red LED that visually indicates when the engines points make contact & the ignition coil is on. When the LED is on, the coil is making continuous multi-sparks. -The coil has a slight hum when it is on but a louder audio buzzer can easily be added to indicate when the coil is on & producing sparks. -The coil has a built-in amp that only sends low current (0.05A) through the points. The ignition points or contact wipes can be built smaller & lighter & unlike conventional tungsten points, softer materials can be used with lighter closing pressure. -The coil works with conventional points or with a low current switch such as a reed switch. -Because the coil unit is all solid state, there is nothing to get out of adjustment. -The coil is built from all new components which are over-rated by almost 50% or more. -The coil is water proof & is sealed in tough UV resistant plastic. -The coil unit is small & compact. It measures 3” high x 2-1/2” long x 1-3/4” wide. -Although tight, the coil unit can fit inside of an antique wooden Ford buzz coil box. There are many of these old buzz coils around that no longer work. With the RMC Impulse Drive coil hidden inside, the old vibrator points can be left on the Ford buzz coil (even though not functional), just for looks. -By having the spark occur when the ignition points or contacts first close, there is less problems with point bounce, contact float, etc. -Under actual tests with a hall sensor, the RMC Impulse Drive Ignition coil could run a high compression single cylinder 2-stroke engine up to 15,000 rpm before misfiring occurs. This would equal about 30,000 rpm for a single cylinder 4-stroke engine. Speeds will increase slightly with smaller spark gaps or lower compression engines. -The high speed (3,700 to 4,600 Hz) multiple sparks provide more heat energy that can ignite a wider range of fuel mixtures. - The coils current flow is pulsed, not continuous. Because of this the unit will not over-heat like a regular coil. (For instance, if the engine running accidently stalls while unattended, there's less chance it will burn up the coil like most conventional points open, single spark coils). -The coil has an internal sink that helps to evenly distribute heat though & out of coil mold. Note that even with this, the coil should not be left on with the points closed continuously for long periods of time (anything over a minute) with higher voltages (over 9 volt). -The spark output of the coil varies with the battery voltage. The working range of the coil is 13.5 volt max (which is about the voltage of an over-charged gel-cell battery), down to lower than 4 volt, (a small buzz spark can even be seen with only 2.5v). The normal working range of the coil for ignition sparks is 6 to 12 volt. Note that with a large spark gap, or a high compression engine, a 12 volt gel cell type battery is recommended. If using the coil with a small spark gap, or a low compression engine, lower voltages can be used. A power supply that puts out at least 2 amps is recommended. -With a fully charged 12 volt gel cell battery, the coil can jump over a 1" long spark gap in cool open air. (Note that this is not recommended). Knowing that open air breaks down around 76,200 volt per inch, this would be the voltage the coil is producing. Note that the output voltages of standard, conventional ignition systems are usually around 20,000 to 40,000 volt. Higher performance systems sometimes reach into the 60,000 volt range. -The RMC Impulse Drive coil is not a capacitor discharge ignition system (CDI) & it doesn't have the risk of a stored capacitor discharge shock. -The coil works without using complex & fragile chips, timers, microprocessors, etc. -The coil works using RMC’s own impulse drive circuit. This is an extremely simple circuit that will self-tune itself to most any coil & the power supplied to it. It was the result of almost 7 years of testing & experimenting. -The coil is simple & easy to wire; there are 4 wires, Red & Black (for battery positive & negative), Green is for the engine frame ground & the other wire (white) is for the insulated point or timer contact. Wiring instructions are molded into the coil. Simple instructions also come with the coil that explain & show pictures how to hook it up. The wire connection leads are 11” long. -For anyone interested, datasheets & graphs also come with the coil. These show things like "Max Spark Gap Length vs. Battery Voltage" & "Max Spark Gap Length vs. Engine RPM" etc. -The RMC Impulse Coil can also be run with an amped Hall Sensor circuit. For those unfamiliar with a Hall sensor, it's a miniature non-contact magnetic pickup that senses a magnetic field. It's usually mounted onto the engine & triggered by the passing of the South pole of a small (1/8") diameter magnet. The Hall sensor & magnet are easy to hide & they are not affected by dirt & oil. The small magnet can easily be fit into a cam gear, the crankshaft, flywheel, etc. Since the Hall sensor & magnet are not affected by point bounce or contact float, they have a wide speed range. -A coil-ready Hall circuit will be available from RMC. The Hall amp circuit easily plugs into the RMC Impulse drive coil. The Hall amp circuit can be purchased separately with the hall sensor, magnet & wires, all for $15. I apologize for the long write-up but hopefully some of this information is useful. If I forgot anything please email me or get a hold of me at; -Nick Rowland 6252 Johnston Rd. New Washington, Ohio 44854 As far as a warrantee, most sellers of electronics do not warrantee there items & there is a lot of good reasons for this. Care was taken to provide a good product with clear instructions. If someone buys this coil & accidently hooks it up to the battery backwards & it is damaged, there is no warrantee. If someone buys this coil & uses it under extreme conditions, with higher voltages than it's rated for, or with extremely large spark gaps, etc., & the coil develops a problem, there is no warrantee. Because of this & not being able to know what all was done to the coil, I cannot offer a return policy but I will however make a fair deal on a replacement unit.
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