Page 1 - 1961 , Volume v.12 n.9 , Issue May-1961
P. 1
H E W L E T T - P A C K A R D
JOURNAL
T E C H N I C A L I N F O R M A T I O N F R O M T H E - h p - L A B O R A T O R I E S Vol. 12, No. 9
1
BUSHED CALIFORNIA THE HEWLETT-PACKARD COMPANY, 1501 PAGE MILL ROAD, PALO ALTO, CALIFORNIA MAY, 961
Two New Transistorized Frequency Counters
with Increased Readout and Low-Frequency Capabilities
THE accuracy, speed and simplicity with kc counter has a 5-digit display system. Each
which measurements can be made with the counter is available with either an in-line read
electronic frequency counter have made it one out or with an improved arrangement of the
of the most useful and popular instruments familiar column readout. Both counters are
available. In the ten years since it was first fully transistorized and are packaged in cab
offered commercially, considerable industry inets only 3i" high. The cabinet style is such
effort has been devoted to further refinement that the standard bench-type instrument can
of digital counting techniques and to expand also be used in a relay rack, if desired, by add
ing the versatility of equipment employing ing a pair of simple brackets supplied with the
these techniques. Drawing from the experience instrument.
of its years of leadership in this field, Hewlett-
N E W R E A D O U T
Packard has recently introduced the electronic
FEATURES
counters shown below as the first of a new gen
In addition to these basic specifications, the
eration of digital frequency and time-measur
new counters have several unusual operating
ing instruments.
conveniences. One of the most apparent of
Of the two new counters one operates over
these is that the readout is steady and continu
the frequency range from 2 cps to 1.2 mega
ous, changing only when the measured count
cycles and the other from 2 cps to 300 kilo
cycles. Both will measure frequency, period, changes. This display storage feature is in con
trast to the usual arrangement wherein the con
and the average of up to 103 periods as well as
the ratio of two frequencies, and both will tinuity of the display is interrupted during the
operate on signals down to 0.1 volt rms. The interval in which the counter is counting. As
higher frequency counter presents its measure is known, display storage requires that each
ments on a 6-digit display system, while the 300 flip-flop in the counting circuitry be duplicated
Fig. 1. Neu- -hp- 1.2-megacycle and 100-kilocycle thus giving much increased low-frequency accu
general-purpose frequency counters are designed racy. Instrument panel is 3^" high or less than
to display measurements in a non-intermittent type height of 5U4GB tube shown in scale for com
readout that eliminates usual visual interruptions parison. Besides in-line type of readout shown,
in readings. Counters are also arranged to measure counters also have a new arrangement of column-
low frequencies by averaging up to 105 periods. type readout (Fig. 8).
P R I N T E D I N U . S . A . C O P Y R I G H T 1 9 6 1 H E W L E T T - P A C K A R D C O .
© Copr. 1949-1998 Hewlett-Packard Co.
