Table of Contents
Advertisement
I
~tJ~ ~TJ~=l=
q
~~ ~R=A=L=
Q
~S=C=RJ ~
TJ PJ!:
INTRODUCTION
1.1
The Frequency Period Meters Type 9057 and 9059 are compact portable instruments
particularly suited to the needs of the communications industry. The instruments
are available in either mains or battery-powered versions, with re-charging facilities
provided in the battery pack.
FACILITIES
Type 9057
1 .2
Direct frequency measurement is provided in the range 1OHz to BOMHz and period
measurement from 1OHz to 3MHz, with four gate times. Sensitivity is better than
10mV over the frequency range. Input is on a single channel with a switched attenuator
which permits a maximum input level of lOOmV r.m.s. to be applied.
Type 9059
1 .3
The 9059 is similar to the 9057, but with two input channels, the facilities on
Channel 'A' being the same as for the 9057. The second input (Channel 'B') is
provided with a separate switched attenuator feeding a pre-scaler assembly which extends
the frequency range to 560MHz. The 10mV sensitivity is maintained up to 500MHz,
decreasing to 50mV at 560MHz. The switched attenuator permits a maximum input level of
4V r.m.s. on Channel 'B'.
·
Display
1.4
The six-digit display employs in-line solid state numeric indicators with automatic
positioning of decimal point. An "overflow" indicator lamp effectively extends the
readout to seven digits.
CONSTRUCTION
1
.5
The circuit assemblies are mounted on a main chassis which is secured to the rear of
the front panel assembly, this complete assembly being inserted in a case which is
attached to the front panel assembly by six screws. The power pack is secured to the rear
of the instrument by hand-tightened bolts, the power connections between the two sections
being made Via an 8-way socket on the pack which mates with a fixed plug on the main
chassis. The front panel has a hinged hood which can be closed to protect the panel when
the instrument is not in use.
PARTS LISTS
1.6
Parts Lists for individual assemblies will be found preceding the layout and circuit
diagrams for each assembly.
1-1
9057/9059
Advertisement
Table of Contents
