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Re: Repairing an ET Ignition System [Re: Magnetoman] #746446
08/22/18 4:24 pm
08/22/18 4:24 pm
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Frazier Park, CA
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Chris Johnson Offline
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The workshop manual gives a rated output of 24 watts for an ET headlamp. Your lighting circuit won’t support that 55/60w headlamp and it will make your tail lamp even worse. Just accept the AC system for what it is, which isn’t safe by modern standards, but neither is riding motorcycles in general.

Chris

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Re: Repairing an ET Ignition System [Re: Mori55] #746451
08/22/18 5:08 pm
08/22/18 5:08 pm
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Stuart Offline
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Hi Mori,

Originally Posted by Mori55
What concerns me more than anything is the tailight.

Originally Posted by Mori55
I want to keep the bike original as possible. Easy to say use for a boat anchor

Joking aside, I appreciate your dilemma but there simply is not any way of 'improving' ET lights. Bear in mind that what eventually drove a wooden stake through the heart of ET and shot it with silver bullet (see where I'm going with the analogies? grin ) was even whoever makes FMVSS regs. (the DOT?) thought it was so bad they had to legislate it out of existence half-a-century ago, by simply mandating the rear lamp stayed illuminated even if the engine stopped. thumbsup So even '68-on TR6C's, T100C's, etc. got essentially the same 12V DC electrics as all the other bikes, that Lucas then concentrated on improving, the latest being essentially still backwards-compatible.

Here in GB, we have this 'Irish' joke - tourist stops beside a local in the middle of nowhere and asks directions; local says, "Ah, well, if I was going there, I wouldn't start from here." With respect, anyone looking at your excellent restoration can't tell whether it has standard ET electrics or a high-output 3-phase alternator and a 100W main-beam headlamp bulb. I appreciate the argument that you would know, but you made the decision and so you have to accept shonky ET lights. If you wanted decent lights, you shouldn't have started with ET.

Coincident with "Magnetoman" being this thread's OP, I asked in your other thread if you'd read his Ariel thread? Reason being necessarily-crap 90-year-old lights is one specific problem he's solved to his satisfaction; would his solution on his 90-year-old bike also work on your 50-year-old bike?

Hth.

Regards,

Re: Repairing an ET Ignition System [Re: Magnetoman] #746536
08/23/18 5:23 pm
08/23/18 5:23 pm
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We have to accept a variety of compromises to ride old British bikes on today's roads. Modern motorcycles have more h.p., better brakes, higher output alternators, electric starters, fuel injection, better suspension, etc. etc. "Upgrading" an E.T.'s lighting coils to later non-E.T. Lucas specifications also "upgrades" you into having regular battery problems while still leaving the lighting well short of that on a modern bike. You're also left with lower h.p., worse brakes, etc. than on a modern bike.

If you don't intend to ride at night except in rare cases where plans go awry, you might find the compromises inherent with an E.T. system (lights that are less than blinding, but never needing to deal with a battery), vs. the compromises inherent with another 50-year old electrical system, worthwhile. I know that I do. But, each person has their own priorities.

I've had to move my Triumph 500 out of the way of my Ariel a number of times over the past year so it's on my mind. It has an E.T. system so it hasn't been connected to a battery tender (and disconnected, and reconnected, etc. as I've had to move it around), or had to have electrolyte topped up, or had a battery die for no apparent reason. I haven't ridden the Triumph in over a year but I know that all I need to do is add fuel and it will start. When I do ride the Triumph it's seldom at night so, for me, the compromises with an E.T. system (vs. those with a battery system) are well worth it.

Anyway, the point of this is it's a tradeoff so you have to decide what factors are more important to you than others. The reason I started this thread was to provide reliable information to allow people to get their E.T. systems working as best as they are intrinsically capable of working. If you can't live with its 35W headlight you should consider a battery system (with its tradeoffs). But, also keep in mind that if you don't understand the E.T. electrical system well enough to get it working properly, making the switch to a different electrical system is likely to cause you many nightmares before you get it working.

Re: Repairing an ET Ignition System [Re: Magnetoman] #747186
08/29/18 9:29 pm
08/29/18 9:29 pm
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Well I’m really happy with the way my ET bike starts! Usually first kick. I was so worried about how it would start.
I can deal with thoughts now that I’m used them. Also some had put a 12v 1157. I got a 6v one and it’s better.
Thanks for all the help.

Re: Repairing an ET Ignition System [Re: Magnetoman] #747483
08/31/18 11:33 pm
08/31/18 11:33 pm
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Re: Repairing an ET Ignition System [Re: Mori55] #747517
09/01/18 5:57 am
09/01/18 5:57 am
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Hi Mori,

Post how you get on?

Btw, risking stating the obvious, you'll need one with red LED for a rear/brake lamp but bear in mind that the rear plate illumination will then be red rather than white.

Hth.

Regards,

Re: Repairing an ET Ignition System [Re: Mori55] #747556
09/01/18 4:13 pm
09/01/18 4:13 pm
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Magnetoman Online content OP

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Originally Posted by Stuart
you'll need one with red LED for a rear/brake lamp but bear in mind that the rear plate illumination will then be red rather than white.
A white LED works just fine because the cover is made of red plastic. The original tungsten bulb emits "white" light, not red.

Originally Posted by Mori55
Found this bulb , what do u think ?
You're buying a light bulb, not some complex mechanism. It's a useful learning experience for you to take the time to read the specs to decide for yourself if its appropriate.

Re: Repairing an ET Ignition System [Re: Magnetoman] #747558
09/01/18 4:29 pm
09/01/18 4:29 pm
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Originally Posted by Magnetoman
[quote=Stuart] A white LED works just fine because the cover is made of red plastic. The original tungsten bulb emits "white" light, not red.



Not very good advice. The original tungsten bulb emits light of many colours, including enough red light to show quite brightly through a red lens.

Many white LEDs are very dim through a red lens.

Last edited by triton thrasher; 09/01/18 4:30 pm.

Amateur Loctite enthusiast.
Re: Repairing an ET Ignition System [Re: triton thrasher] #747563
09/01/18 6:03 pm
09/01/18 6:03 pm
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Originally Posted by triton thrasher
Many white LEDs are very dim through a red lens.
Consumer white LEDs start with a blue-ish spectrum and then use phosphors to spread it to longer wavelengths. This can be seen in the spectrum I measured of a headlamp LED.

Phosphors are inefficient so for this headlamp bulb the manufacturer chose to keep it bright and "white-enough," so there isn't a lot of power in the red. However, because there are regulations on how bright taillights and brake lights have to be, bulbs sold for that purpose have to have enough red to meet those specs.

Because the taillight (from superbrightLEDs) on my Ariel was so bright I was curious about the phosphors that gave it its spectrum so I measured it as well to compare with the headlight bulb so I could see where each of its phosphors had peak emission. Unfortunately I can't find that spectrum, but this post shows that an LED sold as a replacement for a 60 W household bulb has a lot more red than the above headlamp bulb and, as can be seen from the photograph, the light in the Ariel has plenty of power in the red. Again, unless the retailer is breaking the law, a "white" LED sold as a taillight/stoplight bulb will be as bright as the tungsten bulb it replaces.


Attached Files Taillight.jpg
Last edited by Magnetoman; 09/01/18 6:16 pm. Reason: added link to more spectra
Re: Repairing an ET Ignition System [Re: Magnetoman] #747622
09/02/18 11:18 am
09/02/18 11:18 am
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Hi,

Originally Posted by Magnetoman
Originally Posted by Stuart
you'll need one with red LED for a rear/brake lamp but bear in mind that the rear plate illumination will then be red rather than white.
A white LED works just fine because the cover is made of red plastic. The original tungsten bulb emits "white" light, not red.

I appreciate the point but:-

. Why has the advice from LED 'bulb' and 'mat' sellers always been to use LED of the colour required? E.g. both the late-lamented BulbsThatLast4Ever and Paul Goff supplied/supply rear 'mats' and 'bulbs' with a mixture of red - for tail and brake - and white - for numberplate illumination - LED.

. Turn signal/indicator LED are orange/amber.

. Ime, your picture confirms the problem of using white LED behind a red lens - despite the colour of the lens, the emitted light still appears white. I don't know about the US but, in GB, that much white light to the rear would earn an MoT fail or a likely pull by a traffic policeman.

. Similarly, the twin-filament front turn signal/indicator/running lamps bulbs on imported US bikes are frowned upon in GB, to the point where some enterprising person/manufacturer has produced a 'bulb' with a mix of orange and white LED, because the white ('running lamps') LED still appear 'white' through an orange turn signal lens.

Regards,

Re: Repairing an ET Ignition System [Re: Magnetoman] #747630
09/02/18 12:51 pm
09/02/18 12:51 pm
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Originally Posted by Magnetoman
Originally Posted by Stuart
you'll need one with red LED for a rear/brake lamp but bear in mind that the rear plate illumination will then be red rather than white.
A white LED works just fine because the cover is made of red plastic. The original tungsten bulb emits "white" light, not red.

Originally Posted by Mori55
Found this bulb , what do u think ?
You're buying a light bulb, not some complex mechanism. It's a useful learning experience for you to take the time to read the specs to decide for yourself if its appropriate.

I know I’m just buying a light bulb , and I did read the specs. I didn’t know if anyone has tried this , also you said that you can’t improve the ET lighting. Well I did find a AC-DC 6v led bulb. Maybe it will work or maybe it won’t.
And there maybe other members who may be interested in this.

Re: Repairing an ET Ignition System [Re: Stuart] #747640
09/02/18 2:59 pm
09/02/18 2:59 pm
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Originally Posted by Stuart
. Why has the advice from LED 'bulb' and 'mat' sellers always been to use LED of the colour required?
Er, because they don't own spectrometers?

Originally Posted by Stuart
. Ime, your picture confirms the problem of using white LED behind a red lens - despite the colour of the lens, the emitted light still appears white.
That non-red color in the photograph is an artifact of the limited dynamic range of the camera's sensor. The apparent color shifts when greatly overexposed because the dyes over the Red, Green, Blue pixels are less than perfect at blocking light of the "wrong" color. As a result, the other pixels respond to the intense red light and make the lens of the taillight appear not to be red in the photo.

Originally Posted by Mori55
also you said that you can’t improve the ET lighting.
I believe I said you can't improve the output of the E.T. lighting coils. If at some point in the future someone produces a dual-polarity, 6 V LED headlamp bulb with the "filaments" positioned to give proper focus with the Lucas reflector, that certainly would improve the lighting from an E.T. system. A "50 Watt equivalent" LED would draw less power the the current 24 W tungsten bulb.

Last edited by Magnetoman; 09/02/18 4:47 pm. Reason: added response to Mori55
Re: Repairing an ET Ignition System [Re: Magnetoman] #759525
12/17/18 12:20 am
12/17/18 12:20 am
Joined: Nov 2012
Posts: 351
Sacramento, CA
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Magnetoman,
Thank you once again for your attention to detail and your ability to share it with us. You are helping myself and others keep these wonderful machines on the road.

This afternoon 12/15/2018 I sorted another ET system for a perfectly running machine using your information.

Thank you
Denis J


Bikes
- Triumph’s- BSA’s- Norton’s- Matchless’s - Scott’s- A Weslake racer...many others from all over the world.
If it has 2 wheels I might need it.
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Broken Motorcycle Mechanic at The Vintage Monkey in Sacramento, CA ...Old Motorcycle Specialists
Re: Repairing an ET Ignition System [Re: Denis J] #759608
12/17/18 5:04 pm
12/17/18 5:04 pm
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Originally Posted by Denis J
a perfectly running machine using your information.
Thank you for taking the time to post this. Writing a thread like this one takes a fair bit of effort and it's always nice to have confirmation the information in it is being helpful.

Re: Repairing an ET Ignition System [Re: Magnetoman] #761403
01/03/19 6:28 pm
01/03/19 6:28 pm
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Magnetoman,
Question, and I apologize if this was previously covered and I missed it. You mention early on that the points cam is different on the ET system in that it keeps the points closed most of the time, instead of keeping them open. Why is that? I understand why the advance is less, but not why the cam is different.
The reason for my question is that while I do not have a British bike with an ET system, I do have an Italian bike with a low tension flywheel magneto with remote points, which as best as I can tell is the same thing, except the magnets rotate around the outside of the coils in a flywheel instead of the inside in a rotor. A long ago previous owner exchanged the stock manual advance for an automatic advance, which changed the points cam. The bike is not an easy starter, although its better after the flywheel was re-magnetized. I am going to experiment with locking the advance unit, but I am wondering if the points cam also comes into play. I am also looking for the stock parts, but they are not exactly thick on the ground. The bike is a '63 Parilla 250 Wildcat.
Anyway, the article has been helpful to me in understanding how the systems work. Indeed all of your articles are. Here is a piece of AC ignition trivia you may find interesting. Unlike the British or Japanese AC ignition coils, the old Italian ignition coils look just like the DC coils (pretty much the same as a Lucas 6 volt or 12 volt coil). The only way you can tell the difference by looking at them is that the AC coils have an infinity sign or "CA" stamped on the bottom.

Ed from NJ

Re: Repairing an ET Ignition System [Re: Magnetoman] #762074
01/09/19 5:59 pm
01/09/19 5:59 pm
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Originally Posted by edunham
You mention early on that the points cam is different on the ET system in that it keeps the points closed most of the time, instead of keeping them open. Why is that?
Sorry I only saw your post just now. Because this thread is a sticky it appears as the newest post when something is added to it, but if I haven't checked recently it will have "disappeared" again to the top of the list when something is added to a different thread.

Battery/Coil System:
Since there is a capacitor across the points, and since the points are in series with the primary of the coil, because of the cam profile no current flows through the primary when the points are open so no internal heat is generated in the coil through most of the rotation of the cam. When the points close the inductance and resistance of the primary keeps the current from rising very rapidly so d(current)/d(time) isn't large enough to generate a spark. However, after a sufficient dwell time (~L/R) with the points closed the current will have risen to saturate at its maximum value of V(battery)/R(primary). When the points open the current in the primary instantaneously drops to zero causing a voltage in the secondary that is large enough to jump the spark gap. Because the points are in series and the battery always supplies a full 6/12 V the "battery-type" cam profile minimizes the time that full current flows through the coil and thus minimizes the heating.

E.T. (Magneto) System:
The points are in parallel with the primary coil so because of the profile of the cam no current flows through the primary through most of the rotation so no internal heat is generated in the coil. When the points open the smaller inductance of a magneto-type coil combined with the larger total resistance of the primary + stator circuit allows the current to rise rapidly enough to cause a voltage in the secondary that is large enough to jump the spark gap. Because the points are in parallel the "magneto-type" cam profile minimizes the time the current flows through the coil and thus the heating is minimized.

p.s. A few months ago I wrote:
Originally Posted by Magnetoman
If at some point in the future someone produces a dual-polarity, 6 V LED headlamp bulb with the "filaments" positioned to give proper focus with the Lucas reflector, that certainly would improve the lighting from an E.T. system. A "50 Watt equivalent" LED would draw less power the the current 24 W tungsten bulb.
Yesterday I ordered a BFP LED headlamp bulb that is supposed to be dual-polarity, operate anywhere from 6 V to 24 V, and have the proper beam profile. If it actually performs as advertised it will be the silver bullet for the E.T.'s feeble headlight. My Triumph is currently trapped behind other bikes in the garage so it will be a while before I have a chance to test the bulb but I'll eventually report the results here.

Last edited by Magnetoman; 01/09/19 6:10 pm. Reason: p.s.
Re: Repairing an ET Ignition System [Re: Magnetoman] #762147
01/10/19 2:57 pm
01/10/19 2:57 pm
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Thanks for the explanation, MM.
I am not fully following the explanation regarding the the points being in series on a battery/coil and in parallel on a magneto, as the wiring on my mag bike appears to be the same as you would use if it was a battery/coil, i.e., wire from stator coil to + terminal on AC ignition coil (I think, its not in front of me so I don't remember for sure if its the + or - terminal), wire from + terminal on ignition coil to points, wire from condenser to +terminal on AC ignition coil, and wire from - terminal on AC ignition coil to ground. If I replace the AC ignition coil with a battery and the stator with a battery, the rest of the wiring stays the same. Is the difference in the internal wiring of an AC ignition coil as compared to a DC ignition coil?
In any event, my take away is that the point cams are not interchangeable between the systems for reasons having to do with excess heat to the coil and not strength of spark.
Incidentally, years ago, I had Triumph T100C with battery coil ignition, except that I had used a big capacitor as a battery eliminator. The advance unit went bad and I used a 5 degree ET advance unit because I had one and I wasn't aware of the different cam profiles. Ran fine that way for years and then I sold it. Never had any problems with the coils overheating. Just lucky I guess.

Ed from NJ

Re: Repairing an ET Ignition System [Re: edunham] #762170
01/10/19 5:21 pm
01/10/19 5:21 pm
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Originally Posted by edunham
I am not fully following the explanation regarding the the points...
If you look at both types of circuit diagrams, when the points are closed on an E.T. system no current flows through the coil, but when they are closed on a battery system full current flows through the coil. Aside from anything else, this makes the two systems significantly different.

Re: Repairing an ET Ignition System [Re: Magnetoman] #765756
02/18/19 6:09 pm
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I have a new question. It’s about the horn. The bike runs fine everything works as it should. I took the horn apart and got it buzzing pretty loud using a door bell transformer which is AC 8 v. Closes I good find for a power supply.
When I put on the bike , I can barely hear it Sounds very weak. At idle it’ll dim the head light. So I rev it up and it still isn’t any better.
It’s all new harness and horn switch. How much power should be going to the horn ? How do I check it.? It’s a new 5 wire stator.
Any help would be appreciated.

Re: Repairing an ET Ignition System [Re: Magnetoman] #765762
02/18/19 6:57 pm
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Originally Posted by Mori55
When I put on the bike , I can barely hear it
Loud pipes save lives, ET horns don't...

Originally Posted by Mori55
At idle it’ll dim the head light. So I rev it up and it still isn’t any better.
I don't remember what the resistance of the horn should be, but it's wired in parallel with the light so at all rpm the power (35W max.) is shared between the two based on the relative resistances. Have you tried the horn with the light off?

Re: Repairing an ET Ignition System [Re: Magnetoman] #765797
02/19/19 12:03 am
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Well I shut the light off and it’s buzzing better but for some reason the high beam indicator blows when I hit the high beam button. The biggest pain for me is the bike has to be running to check this stuff. Since I’m not good with a meter I’m not sure what to set on to check it. Where is she going to kick me out tonight. To me if it was a bike with a battery I could just turn it on and check things.

Re: Repairing an ET Ignition System [Re: Magnetoman] #765848
02/19/19 5:42 pm
02/19/19 5:42 pm
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Originally Posted by Mori55
To me if it was a bike with a battery I could just turn it on and check things.
You've already determined that the stator's lighting coils are working (the lights come on) as are its ignition coils (the bike runs), so everything else can be checked with an ohmmeter. The only thing a battery system would do for you is supply a voltage to check with a voltmeter at various locations, but the battery inside an ohmmeter accomplishes the same thing except now you check ohms.

Using an ohmmeter and the circuit diagram you check between various points on the wires, as well as from those points to the frame, to make sure the resistances are what they should be and that there are no conduction paths that shouldn't be (e.g. a short to the frame). As an example of what they "should" be, you already know the headlight works so measure the resistance directly across the bulb. Then, with the headlight switch 'on', measure the resistance between the connector in the brown/blue wire that is closest to the stator and the frame. The difference between those two measurements tells you the total excess resistance in the headlamp circuit which, ideally, would be 0. If it is a significant fraction of the bulb's resistance (say, 10%) you need to find and eliminate as much of that excess resistance as you can by checking all the connectors in the circuit.

The first place I'd check is the resistance across the horn button. It should be infinite except when pushed, and then very close to 0 when pushed. If the horn's resistance were 10 Ohms an additional resistance of only 1 Ohm would dissipate 10% of the available power in the switch, leaving that much less to operate the horn.

An inexpensive ohmmeter will have trouble giving good readings for small resistances, in which case you should touch the leads together to see how much the offset is from 0 is (e.g. two needle widths), then measure the small resistance (e.g. three needle widths) and estimate the resistance from how many needle widths it is between the 0 and 1 marks on the ohmmeter's face. If the extra 1 needle width in this example corresponded to ~0.1 Ohms on your meter that would represent an excess power loss of ~0.6 W in a 6 V circuit, which wouldn't be enough to have an effect on the operation of your horn.

Re: Repairing an ET Ignition System [Re: Magnetoman] #765852
02/19/19 5:55 pm
02/19/19 5:55 pm
Joined: Apr 2017
Posts: 759
NJ USA
M
Mori55 Online content
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Mori55  Online Content
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Joined: Apr 2017
Posts: 759
NJ USA
Thanks !

Re: Repairing an ET Ignition System [Re: Magnetoman] #765910
02/20/19 2:44 am
02/20/19 2:44 am
Joined: Apr 2017
Posts: 759
NJ USA
M
Mori55 Online content
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Mori55  Online Content
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Joined: Apr 2017
Posts: 759
NJ USA
Magnetoman
Two questions if you please. Would a 25/25 bpf halogen bulb work for the headlight ? I’ve also seen cbs has a led bpf that you can get 6 volts +or - ground. Could I use a bridge rectifier with this bulb since it’s DC.?
Not really sure about this stuff.
I saw this video, would this work ?
https://youtu.be/eKqrIvJGeZg
Thanks.

Last edited by Mori55; 02/20/19 2:55 am.
Re: Repairing an ET Ignition System [Re: Magnetoman] #765911
02/20/19 3:06 am
02/20/19 3:06 am
Joined: Sep 2013
Posts: 1,910
Pacific northwest
Q
quinten Online confused
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quinten  Online Confused
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Joined: Sep 2013
Posts: 1,910
Pacific northwest

Weak ac horn ?

The cold resistance of metal is not even close to the hot resistance .
The resistance of the headlight filament can change 10-fold in a millisecond .

This can play hell with the limited power available. For ET lighing and horn .

As the horn is added , it bleets like a sick lamb
.... the bulb cools and becomes less resistive ... and again steal current from horn .
The circuit will see-saw ... and kind of work , if you tap the horn , but will equalize if you hold down the horn .
The inrush current gives
a different result than the stabilized circuit .

.

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