Model 950

Location of Front Panel

Terminals and Controls

1784 Chessie Lane, Ottawa, IL 61350 • Tel: 800/252-7074, 815/434-7800 • FAX: 815/434-8176

e-mail: sales@freqdev.com • Web Address: http://www.freqdev.com

4

100

B

A

20

OUT

x100

10

0

A-B

A

GND

OFFSET

ON

TUNEABLE ACTIVE FILTER

FREQUENCY

INPUT

GAIN

(dB)

+

x1

R

200

500

50

20

10

CORNER

IN Hz

950

N

E

G

A

-

Location of Front Panel Terminals and Controls

C&D

F

E

B

H

I

FRONT PANEL

A. POWER Status Lamp: This red LED

indicates whether or not the power to the

analog filter circuitry of a Model 950

instrument is on.

B. INPUT Switch: This three position

toggle configures the instrument for

either differential inputs (A-B), a single-

ended input (A), or input nulling (GND)

which grounds both the (A) and (B) input

terminals.

C. & D. (A) and (B) Input Terminals:

This pair of shielded, female BNC

connectors accept signal inputs (A) and

(B).

The instrument applies a non-

inverting gain to input (A) and an equal

but opposite inverting gain to input (B)

while the GAIN switch sets the magnitude

of differential gain to 0, 10, or 20 dB. The

BNC

shields

have

been

internally

connected to the instrument ground.

E. GAIN Switch:

This three-position

toggle switch selects an overall filter gain

of 0, 10, or 20dB.

F. OFFSET Adjust: This adjustment is

intended to zero the offset that results

from the instrument’s own circuitry and

does not provide for wide range offset to

remove dc input signals.

G. CORNER FREQUENCY Selector

Switch (10-500Hz):

This six position

rotary switch selects the digit value of the

corner frequency. The switch selectable

values are 10, 20, 50, 100, 200 and 500,

H. MULTIPLIER Selector Switch: This

two-position toggle switch multiplies by a

factor of either 1 or 100x, the value set

on the CORNER FREQUENCY selector

switch.

I. OUT Terminal:

This terminal is a

female BNC connector. The shield on

the BNC is internally connected to the

instrument ground.

REAR PANEL

J. IDENTIFICATION LABEL: This label

identifies the date of manufacture, serial

number, filter type and operating power

requirements.

K. POWER CONNECTION:

Denotes

power plug location.

L. POWER ON/OFF Switch:

A two-

position toggle switch on the back panel

Power Module that interrupts/completes

the power circuit.

M. Voltage Selector Module:

115V Operation

The power module window shows the

operating voltage (115V or 230V).

At

time of shipment, the voltage window will

be set to the 115V position.

230V Operation

For 230V operation, use a small flathead

screwdriver to pry open the fuse module

door. Remove the fuse cartridge, fuse

clip and single fuse for 115V operation.

Install two 5 X 20 mm 250V, 0.1A fuses

into the fuse cartridge, rotate and insert

fuse cartridge so 230V is visible in fuse

module door when closed.

A

115v

FUSE

(250V 0.1A)

(250V 0.1A)

NOM. FREQ.

60 Hz

50 Hz

230v

APR.01

MADE IN U.S.A

SN: 00105

950L8L

SELECT

Location of Rear Panel Terminals and Controls

J

M

L

G

K