TB 9-6625-336-35
SECTION I
IDENTIFICATION AND DESCRIPTION
This bulletin provides instructions for the
1. Test Instrument Identification.
calibration of Frequency Comparator CM77 and CM77A; and Transfer Oscillator, Hewlett-
Packard Models 540A and 540B. The manufacturer's manuals and TM 11-6625-493-15
were used as the prime data sources in compiling these instructions. The equipment being
calibrated will be referred to as the TI (test instrument) throughout this bulletin.
a. Model Variations. Described in text.
b. Time and Technique. The time required for this calibration is approximately 2
hours, using the dc and low frequency technique.
2. DA Form 2416 (Calibration Data Card)
prescribed by TB 750-25-1. DA Form 2416 must be annotated in accordance with TB 750-
25-1 for each calibration performed.
b. Adjustments to be reported on DA Form 2416 are designated (R) at the end of the
sentence in which they appear. When adjustments are in tables, the (R) follows the
designated adjustment. Report only those adjustments made and designated with (R).
3. Calibration Description. TI parameters and performance specifications which
pertain to this calibration are listed in table 1.
Table 1. Calibration Description
Test instrument parameters
Performance specifications
Line voltage regulation
115 or 220 V ac 10%, 50 to 1,000 Hz, 115 W
Fundamental frequency:
Range
100 to 200 MHz
Output
Approx. 2 V into 50Ω
Stability
< 0.002% change per minute after 30 minute warmup
Dial accuracy
0.5%
Amplifier:
Gain
Adjustable to 40 dB max
100 Hz to 2 MHz
Undistorted output (Max)
1 V rms usable signal across 1 kΩ load
Frequency range
100 Hz to 200 kHz
Vertical deflection sensitivity
5 mV rms per inch
Horizontal sweep:
External
1 V per in., 20 Hz to 5 kHz
Internal
Power supply frequency with phase control
2
