Thor.......
I bought mine from Signal Dynamics in Florida (www.signaldynamics.com). I
believe this is the company who built the first modulator--if NHTSA's web
site is any documentation. They are very nice to do business with, and they
supported their unit, when I had some problems with it originally. The unit
I have now works fine. I can't remember the prices exactly, but its between
$65 + 90.00. You can order it off their web page. Kriss used to make one,
and I assume they still do...but..., if you go to Google and do a search on
"headlight modulators" I'm sure you'll find others.
To make a 9 month story a bit shorter, the entire situation arose because
the state of Maryland was misinformed on the differences between a modulated
light and a blinking one (see below). It IS illegal to have a BLINKING
light on the front of a NON emergency vehicle--also a Federal MVSS--if I'm
not mistaken.
Back in about 1985 I had one on my Suzuki 850, and I got a ticket for having
a blinking headlight, which, as I noted is illegal. Instead of
investigating, I paid the ticket. Turns out I might have been able to get
around it then, but I didn't know where to begin looking.
In the late 90s, after I got my GTS, I wanted to put one on my bike and
asked the MD MVA Administrator to make a ruling (she's a rider too, and
loves the MD Motorcycle Safety Program, for which I'm an instructor).
Instead of doing it my way, she felt it would be better to go through
channels and see how the MD state police felt about it--as they are
responsible for making the traffic laws in MD. Turns out they thought they
were illegal. So I contacted several groups who eventually put me in touch
with NHTSA and I eventually found a lighting compliance lawyer. I told him
that MD was out of compliance with the rule, and he eventually got through
to the state of MD and helped them realize the wrongness of their thinking.
The entire process took 9 months.
Last August I got stopped by a MD Trooper for having a blinking light on the
front of my bike. I explained to him that modulators were OK, and said I
had a letter at home from the State Police which said that was the case. He
took my info, and I faxed the letter to him. No more problem, except then I
had to write to the Superintendent of the MD state police and find out why
they hadn't put the change in the Traffic Articles (what the regulations are
called here in MD)--I'm still not 100% sure its been done, but I'll follow
up with them as necessary.
Please note that the difference between a modulated light and a blinking
light is the definition: a modulated light cycles from high power to low
power then repeats. A blinking light cycles from ON to OFF then repeats.
That's the difference and that's how the modulated light gets around the
definition of being a blinking light. Personally, I don't see any
difference in blinking or modulated as far as the final product is
concerned. Here in the DC area, I call this kind of thing "bureaucrat-eze".
I'll have to remember to check the MD Traffic Articles and see if the
changes have been made.
Below is the section that covers headlight modulators. I got it off the
net. It's in a government data base but I actually had to call someone
locally to find it. As long as the modulator meets these specs its legal.
Remember that this is in the United States Code, which automatically over
rides state laws. If I'm not mistaken all states are now in compliance, but
you might want to check the regulations in Colorado to make sure. If you
need the name of the lighting compliance lawyer at NHTSA, let me know.
[Code of Federal Regulations]
[Title 49, Volume 5, Parts 400 to 999]
[Revised as of October 1, 1996]
>From the U.S. Government Printing Office via GPO Access
[CITE: 49CFR571.108]
[Page 217-285]
TITLE 49--TRANSPORTATION
PART 571--FEDERAL MOTOR VEHICLE SAFETY STANDARDS--Table of Contents
Subpart B--Federal Motor Vehicle Safety Standards
Sec. 571.108 Standard No. 108; Lamps, reflective devices, and associated
equipment.
S1. Scope. This standard specifies requirements for original and
replacement lamps, reflective devices, and associated equipment.
S2. Purpose. The purpose of this standard is to reduce traffic
accidents and deaths and injuries resulting from
(intervening pages deleted by Henry S. Winokur)
[[Page 243]]
(intervening paragraphs deleted by Henry S. Winokur)
S7.9.4 Motorcycle headlamp modulation system.
S7.9.4.1 A headlamp on a motorcycle may be wired to modulate either the
upper beam or the lower beam from its maximum intensity to a lesser
intensity, provided that:
(a) The rate of modulation shall be 240 <plus-minus> 40 cycles per
minute.
(b) The headlamp shall be operated at maximum power for 50 to 70
percent of each cycle.
(c) The lowest intensity at any test point shall be not less than 17
percent of the maximum intensity measured at the same point.
(d) The modulator switch shall be wired in the power lead of the
beam filament being modulated and not in the ground side of the circuit.
(e) Means shall be provided so that both the lower beam and upper
beam remain operable in the event of a modulator failure.
(f) The system shall include a sensor mounted with the axis of its
sensing element perpendicular to a horizontal plane. Headlamp modulation
shall cease whenever the level of light emitted by a tungsten filament light
operating at 3000 deg. Kelvin is either less than 270 lux (25 foot-candles)
of direct light for upward pointing sensors or less than 60 lux (5.6
foot-candles) of reflected light for downward pointing sensors. The light is
measured by a silicon cell type light meter that is located at the sensor
and pointing in the same direction as the sensor. A Kodak Gray Card (Kodak
R-27) is placed at ground level to simulate the road surface in testing
downward pointing sensors.
(g) When tested in accordance with the test profile shown in Figure
9, the voltage drop across the modulator when the lamp is on at all test
conditions for 12 volt systems and 6 volt systems shall not be greater than
.45 volt. The modulator shall meet all the provisions of the standard after
completion of the test profile shown in Figure 9.
(h) Means shall be provided so that both the lower and upper beam
function at design voltage when the headlamp control switch is in either the
lower or upper beam position when the modulator is off.
S7.9.4.2(a) Each motorcycle headlamp modulator not intended as
original equipment, or its container, shall be labeled with the maximum
wattage, and the minimum wattage appropriate for its use. Additionally,
each such modulator shall comply with S7.9.4.1 (a) through (g) when
connected to a headlamp of the maximum rated power and a headlamp of the
minimum rated power, and shall provide means so that the modulated beam
functions at design voltage when the modulator is off.
(b) Instructions, with a diagram, shall be provided for mounting the
light sensor including location on the motorcycle, distance above the road
surface, and orientation with respect to the light.
Regards,
Henry S. Winokur
94 GTS1000, AMA, MRF,
Nationally Certified Riding Instructor
Columbia, MD Ride for Kids Task Force
West Bethesda, MD USA
