TM 9-4910-700-14 & P
CHAPTER 1
INTRODUCTION AND SPECIFICATIONS
1-1. INTRODUCTION. This manual covers 1-3. DESCRIPTION, The test set has two
panel meters which simultaneously dis-
test set, tachometer-dwell.
The manual play the engine r.p.m. and dwell angle.
contains instructions for operation and The tachometer operates off of an in-
direct secondary impulse pickup which
maintenance of the test set.
SAFETY PRECAUTIONS, The following can be clipped around any of the spark-
1-2.
plug wires. The dwell meter is con-
safety precautions are applicable to
nected across the distributor points to
the use of the test set.
ground. It has provisions for meas-
//WARNING //
CAUTION SHOULD BE EXERCISED WHEN WORKING uring dwell angle directly in degrees
for 8, 6 and 4 cylinder four cycle
WITH SECONDARY IGNITION SYSTEMS. HIGH
engines, Errors in r.p.m. will result
VOLTAGE IS PRESENT WHICH CAN CAUSE IN-
JURY DIRECTLY THROUGH ELECTRICAL SHOCK, when used with 2 cycle engines.
1-4. SPECIFICATIONS. Table 1-1 gives
OR INDIRECTLY THROUGH REFLEX ACTIONS
the specifications and pertinent data
RESULTING IN INJURY. ALSO, WHEN WORK-
for the test set.
ING IN THE ENGINE COMPARTMENT OF AUTO-
MOBILES AND TRUCKS, CARE SHOULD BE TAKEN
TO AVOID ROTATING PARTS SUCH AS FAN
BLADES AND BELTS.
TABLE 1-l. SPECIFICATIONS AND DATA
FUNCTIONS
0-1000rpm; 0-5000rpm
Ranges
3% of full scale readings
Accuracy
Dwell
0-60 degrees
Ranges (6 and 8 cyl engines)
0-90 degrees
Ranges (4 cyl engines)
0-100 percent
Ranges (all configurations)
3% of full scale readings
Accuracy
Point Voltage
0-1 volt
Ranges
.03 volts at .2 volts
Accuracy
Two 4 1/2" Meters
Display
Vehicle battery 12-16V
Operating Power
Accessories
battery power, lead for dwell connection
Integral carrying case.
9 1/4 x 10 x 3 1/4
Size
Weight
Approximately 9 LBS
1-1