TFT 844 - Page 4

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SECTION 1
GENERAL INFORMATION
1.1
General Description
The TFT Model 844 FM Modulation stereo monitor
provides both
on-the-air and off-the-air monitoring of FM broadcast
stations operating in the frequency range of 88 to 108 MHz.
The three meter format allows stereo measurements
while monitoring
total modulation, Left and Right channels. Push
button switches allow monitoring of the following functions on the
LEFT/TEST Meter: left Channel, Right Channel, 38 kHz, 19 kHz pilot,
L+R, L-R, Total modulation, AM noise, and multipath.
Front panel
indicators show when a preset
modulation percentage
is exceeded on either positive or negative
peaks.
Front panel controls allow the monitoring of
two
different frequencies without resetting.
Absence of modulation and carrier failure alarms
are available
as options.
1.2
Specifications
RF SECTION
Frequency range .....
On-site RF input voltage
Antenna input voltage
Tuning . ....... .
AGC range ....... .
Input impedance, antenna
Input connector, antenna
MODULATION METERS, TOTAL
Deviation for 100% indication
Meter Range .•...••
AC Voltmeter range .
Accuracy
(5-KHz tone)
Frequency response
Characteristics .
Remote output .
. 88-108
MHz, tunable in 50 KHz steps
. 1 to 10 volts rms
250 uV to lOOmV
Two 4-digit switches and a push-
button switch for
selecting station
A or B .
. 60 dB
75 ohms
Type F
• + 75 KHz peak to peak
• 1Y to 133% modulation
. Oto -50 dB in 10 dB steps
. +
2% at all modulation levels
+ 0.1 dB typical,+ 0. 25 dB max from
50 Hz to 120 KHz -
Quasi-peak reading
circuit
Suitable for driving remote readout
meter panels.
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