These rugged counters are at home on the production line, in
the lab, or in the field and do the work of counters costing
much more. They measure frequencies to 125 MHz, 250 MHz or
520 MHz (depending on model), period of signals to 2 MHz,
period average to 10 ps resolution and totalize to 9,999,999
Full autoranging is supplemented by selectable four-range
manual operation. In autorange, the display is automatically
filled to a maximum 7-digit readout. A unique hysteresis
capability eliminates undesirable up-and-down ranging for
This automatic feature is activated every time you select a
new range orfunction, which means you never have to wait for
a second reading, the
first one in the new measurement sequence is always correct.
Autoreset saves time and reduces errors.
Automatic Clean Dropout
The 1911A and 1912A Channel B input has a circuit which
automatically monitors the input and gives you instant
warning in the form of zero readout whenever your input
signal falls below the sensitivity threshold of the trigger
circuit. When the signal level returns to an acceptable
level, the counter locks on for a correct reading.
A basic sensitivity of 15 mV, backed by Fluke’s conservative
design margin, guarantees you will get reliable, solid
readings every time. In practice, a typical sensitivity of
10 mV will be experienced.
Versatile Time Bases
The standard 0.5 ppm per month timebase assures excellent
long term stability for bench, production or field use. A
convenient rear panel external timebase input jack and
switch let you operate from your own 10 MHz frequency
standard at any time. Choice of optional time bases with
improved aging rates and temperature stabilities allows you
to purchase only as much stability as you’ll need in your
Input Signal Conditioning
Each counter offers trigger level and attenuator controls
which operate over the dynamic range of the input to permit
accurate readings in the presence of noise. Even ringing TTL
signals can be accurately measured. In addition, the 1911A
offers a separate 50 ohm input for 50 MHz to 250 MHz and the
1912A does the same but goes to 520 MHz.
All three counters are available with rechargeable batteries
for field portability. Order 1910A -01,1911A-01, or 1912-01.
Four hours minimum operation gives you plenty of opportunity
to solve those tough field service problems