Chronograph Results and variables that effect readings…….
The spread between the existing brands of chronographs on the market today is aprx. 8.0%. This has a lot to do with the quality of
the sensors & components used, the distance in which the sensors
are spaced apart, and the firmware design of the product itself.
Variables that will effect results are as follows:
1. Temperature, altitude, & the effects these have on different powders.
2. Temperature of the barrel and the ammunition itself. a cold
barrel will produce different results from a very hot one. The same
with the ammunition.
3. Lighting - MUST be balanced on both sensors evenly.
If the sun changes position, you must maintain a balanced condition on
both sensors. Whether in bright sunlight (using the top screens) or on
shady days (in which the top screens are optional), it is critical to
maintain a balanced situation on both sensors. DO NOT position a
chronograph with the sunlight directly behind or in front of your
shooting position. In this situation, the light will always be stronger
on the sensor closest to the position of the sun. Relocate to another
position where the light is to the left, right, or overhead positions.
It is possible to tilt a tripod panhead allowing the screens to angle
themselves toward a late afternoon light in order to maintain a
BALANCED diffused light on both sensors. Remember to also angle your
shooting position to prevent damaging the equipment with a stray shot.
4. Muzzle blast - If the muzzle blast reaches the first sensor
before the projectile, your results may be in error or not recorded at
all. If the muzzle blast causes your screens to shake, the readings
could also be affected. Suggestion - when using high powered rifles
move back away from the chronograph sensors (12 - 18 feet), until
proper velocities are recorded, and then move forward one foot at a
time, to determine the closest distance at which each weapon will
perform at. Then record that information for future use. Different
calibers, brands, barrels, and ammunition will affect the distance, so
it may be necessary to test each accordingly.
5. The CED Infrared screens are designed for use when mother
nature is not cooperating or for times and locations where insufficient
light exists. If they are used under bright sunlight condition, it is
possible that the sunlight may over-power them or create an in-balanced
condition. It is critically important on ALL chronographs to maintain a
BALANCED light condition on both sensors. Therefore, in such conditions
re-position the chronograph to an area of shade away from the sunlight,
or remove the infrared screens and use natural sunlight in a balanced
position, or cover the infrared screens with a large cardboard to
prevent natural sunlight from reaching the sensors.
6. Spacing. Make sure that your sensors are properly positioned
and tightened. If they are off by even 1/16" it will cause incorrect
readings. Each sensor has an internal pressure plate. Slide the sensor
completely on the mounting bracket until it fits snugly and then
tighten the custom pressure plate from the bottom of each sensor until
it stays firmly in place. DO NOT over-tighten as it may become
difficult to remove later.
7. Glints - If there is water, sand, snow, or bright concrete on
the ground below your tripod / chronograph set-up, the sunlight may
bounce (reflect) light off the ground surface shining it back up onto
the projectile, which in turn may prevent the sensors from detecting a
light drop (shadow)of the projectile, resulting in a poor or no reading
situation.
8. Indoor - Fluorescent lighting is the kiss of death to any
chronograph system. Their light does not allow the sensors to "see" the
projectile properly. Additionally, as all fluorescent lights "flutter",
it is possible for the chronograph sensors to detect this fluttering
which in turn will create false velocity readings. The chronograph may
fill itself with velocities in a short period of time, all caused by
the overhead lighting itself. Cover the top of the IR screens if this
type of lighting is near your chronograph set-up to prevent it
interfering. Also make sure that no additional light is penetrating
onto either sensor which could then create an in-balance of light on
them.
9. Some ranges are designed with small narrow bays or short
backdrops, which may cause excessive sound wave and / or muzzle blast
problems. These have been known to cause interference with chronograph
results.
10. When using the CED Infrared in an indoor shooting range with
AC electricity to power the infrared screen set, make sure the AC
supply itself is a full 110V output. If the range is located a great
distance from the power transformer, it is possible that the output is
less than 110V and this may prevent proper performance. Customers in a
few cases have found that although they got green lights on both IR
screens, no recordings occurred. In such cases, it is better to use the
NiMH Battery Pack instead. When the switch to the NiMH Battery pack was
made, the problem ceased.
11. Other variables - Depending on the quality of the
chronograph & sensors, other variables such as mobile phone
transmissions and high electrical tension poles or electrified fencing
can all have effects on chronograph performance. Even high amounts of
static electricity from summer thunder storms in the area of use can
result in problems. In such cases, change the location of use or wait
for better weather conditions to occur.
One method of testing the main unit & sensors of CED Chronographs to see if they are functioning is the flashlight
test! This test can be conducted in your home, as it requires no actual
shooting or the complete set-up of the system.
Install a fresh battery in the main unit, but DO NOT turn it on!
Plug in BOTH sensors into their proper "START" & "STOP" jacks.
Position the two sensors "back to back" so that they are touching each
other. Make sure the sides, which have the square holes for placement
of the mounting bracket are facing each other. Now, turn on the main
unit. Make sure that you see the display screen appear with the "0000"
showing. Once you have done this, take a flashlight, turn it on and
while holding it 2-3 inches above the sensors, run the light beam (as
FAST as you can) over BOTH sensors. Make sure that you cross over the
FIRST sensor (the one plugged into the START jack) first and then over
the second sensor that is plugged into the STOP jack. If you do this
correctly, you should see a recording on the display screen ranging
from 70 fps up to 300+ fps. This will show you that both the sensors
and the main unit are functioning! If you continue to see no velocity
recorded on the main unit, but only "0000", then a problem with either
one or both sensors exists or with the main unit itself.
For customers who own the Infrared Screen Sets, another method
of testing the equipment is to set-up the chronograph completely in the
home using the infrared screens and to shoot rubber bands through the
chronograph. Remember, the system is designed not to record velocities
under 50 fps, so it is necessary to shoot the rubber bands faster than
this speed to be recorded.
It is sincerely hoped that the above information provided is of
assistance in answering most of the questions that arise during
chronograph use.
IMPORTANT INFO (CED Millennium Chronograph Model)
We have learned of a problem with some USB adapters that has
affected people trying to download to USB ports on Windows XP systems
with the CED Millennium Chronograph. It seems a company called
Prolific, that makes USB chipsets, released a horrible Windows XP
driver earlier this year. The drivers are reported to do all sorts of
bad things and is difficult to remove. There are reports of symptoms
that look like a virus, system lockups, "The infamous blue screen of
death", etc. Some systems have been reported to be so messed up that
the only cure is to reformat the hard drive.
Unfortunately there are several manufacturers of USB chipsets
and internal components are never displayed on the finished adapters so
it is impossible to know what brands are affected.
We used to recommend Keyspan adapters but their's no longer
seems compatible with your chronograph. I believe it is because they
only support devices with full hardware handshaking.
We now recommend people to buy their USB adapter from
http://www.serialIO.com. Theirs is bundled with drivers that work with
simple devices like the Millennium and will not cause Windows system
problems. They even have drivers for OSX!
Please note that the new CED M2 Chronograph comes with a
built-in USB port and cable for easy downloads to any PC. However, the
software is not Mac compatible.