Electro-Metrics EM-2115, Instruction Manual

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EM-2115 3.0 PERFORMANCE CHECK
(EM2115S3-11)
Example:
Frequency Range 1 IF = 175 kHz.
Frequency Indication = 22 kHz
Image Frequency = 2(175 kHz) + 22 kHz = 372 kHz.
Thus for the example shown, the Image Frequency is 372 kHz.
e. Increase the Signal Generator output level by 30 dB. Tune the Signal Generator
for a peak indication on the analog meter of the EM-2115.
f. Subtract the digital meter reading from the +60 dB(µV) reference indication and
add 30 dB to the difference. This figure will be the Image Rejection for the Fre-
quency Range and frequency selected.
g. Repeat Steps b thru f for the mid-frequency points of Frequency Ranges 2-15 us-
ing the following information.
IF Frequency Vs Frequency Range
0.009-0.070 MHz: 175 kHz
0.070-0.500 MHz: 1st IF = 1.6 MHz, 2nd = 175 kHz
0.500-3.4 MHz: 175 kHz
2.4-30 MHz: 1.6 MHz
20-100 MHz: 8.7 MHz
100-200 MHz: 1st IF = 38.7 MHz, 2nd IF = 8.7 MHz
200-500 MHz: 1st IF = 68.7 MHz, 2nd IF = 8.7 MHz
500-1000 MHz: 1st IF = 98.7 MHz, 2nd IF = 8.7 MHz
IF Bandwidth Setting
0.009-3.4 MHz = 200 Hz
2.4-30 MHz = 1 kHz
20-1000 MHz = 100/120 kHz
3.4.9 IF Rejection
Specification: 45 dB minimum
Equipment required: Signal Generator
a. Set the front panel controls as follows:
DETECTOR ...................................................AVERAGE
SAMPLE TIME Control ................................Mid-range.
FREQUENCY RANGE .................................0.009-0.035 MHz.
FREQUENCY INDICATION .......................0.220 MHz.