Timer

The Model J tachometer/timer is a highly reliable,
quartz-accurate, vibration-proof instrument which offers
several advanced features not found on other similar
products. It is economically priced and available in both
single and dual engine versions and is easy to install.
A single pushbutton switch is used to place the
instrument in different modes which display engine RPM,
time of the last flight, current flight time, total engine time
or the current redline setting. These are all viewed on a
highly visible liquid crystal display (LCD) which does not
washout in bright sunlight as light emitting diodes
sometimes do. It has 1/2" high characters and is easily
readable from a distance.
The unit is first turned on by pressing the multifunction
pushbutton switch. It then momentarily
illuminates all of the segments of the LCD to verify that
all numerals are functioning properly. After about two
seconds, the display then continuously alternates
between total accumulated engine hours and the
duration of the last engine operation (basically, the
duration of the last flight). If the engine is not started
within the next three minutes, the instrument shuts itself
off and will retain and display the same information when
turned on again.
If the engine is started, the last flight time is
cleared to zero and the internal timers start advancing.
The display then shows rotational speed in 10 RPM
steps to a maximum of 19,990. If the speed exceeds the
internal redline setting, the display flashes on and off.
The redline is easily set via the pushbutton switch in 50
RPM steps, and is retained in continuous memory until
changed to a new value. To prevent accidental changes,
the method used to alter it is simple and easy to
remember, yet it must be done intentionally. If the
pushbutton is depressed while the engine is running,
RPM is temporarily replaced by the time of the current
engine operation (the current flight time) for about two
seconds.
Once the engine is shut off, the display alternates
between the total/last time format again for about three
minutes before shutting itself off. If the pilot forgets to
enter the flight time in the log, its still in memory and can
be displayed for another three minutes by pressing the
pushbutton again.
The placement of an internal jumper block
configures the instrument for 0.5, 1, 2, 3, 4, 5, 6 or 7
pulses per revolution. This is compatible with most
single and multi-cylinder 2 or 4 stroke engines and other
settings can be provided on special order at no additional
cost. Some special order devices have included 1.5
pulses per revolution for a 3 cylinder Subaru engine and
4.5 pulses per revolution for a popular 9 cylinder radial.
The dual engine version (Model J2) incorporates a
simple two position toggle switch to select which engine
RPM is being displayed. Although only one RPM is
displayed at a time, the internal electronics constantly
monitors both. If either engine goes over redline,
regardless of which is being displayed, the LCD flashes
on and off to alert the pilot to the potential problem. Also,
since it is uncommon to operate only one engine at a
time, the dual model still uses only one set of timers,
which are advanced if either engine is operating.
For those electronics buffs who have computerized
instrument consoles, the unit includes a computer
interface which can be used to record data or display it in
a custom format on accessory equipment. The current
flight time and the RPM of both engines (if a dual model)
is output in a standard, serial format at approximately
two times a second.
The instrument is powered by a single internal 9V
battery. Lifetime