PRC-70 and units of the set.

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MIL-PRF-49118B(CR)

3.5.16.1 Suppressed carrier (SSB, CW and FSK). Suppressed carrier shall be at least

45 dB below the PEP.

3.5.16.2 Lower sidebands. Lower sidebands shall be at least 50 dB below the PEP.

3.5.16.3 Intermodulation Distortion Products (IDP). IDP shall be at least 25 dB below the

two equal amplitude tones modulating the transmitter to the rated PEP in the 2 to 29.9999 MHz

range. The IDP shall be 20 dB below the two equal amplitude tones in the 30.0 to 75.9999

frequency range. When tested in accordance with paragraph 4.5.16, 10% of all IDP data points

(3rd and 5th order both high and low products over the 2 to 75.9999 MHz range) can be up to 3

dB above the specified minimum IDP suppression level and 1% of all data points (3rd and 5th

order, high and low products 2 to 76 MHz range) can be up to 5 dB above the specified IDP

suppression level.

3.5.16.4 Harmonics. The level of harmonics and all other spurious outputs other than

those described above shall be in accordance with 3.7.

3.5.17 Hum and noise. The hum and noise level shall be measured for the inputs and

frequencies of 4.5.16. Hum, ripple and other extraneous noise shall be at least 40 dB below the

output level of either of two equal amplitude tones modulating the transmitter to rated PEP

power for high or low power operation (see 4.5.17).

3.5.18 Transmitter audio frequency response. The audio frequency response shall be

within 4 dB peak-to-valley from 500 Hz to 3000 Hz in all modes of operation. The response at

250 Hz shall be down at least 10 dB from a 1.0 KHz reference and the response at 300 Hz shall

be down at least 6 dB from a 1.0 KHz reference (see paragraph 4.5.18).

3.5.19 Overall wideband response. The overall wideband performance from the

transmitter input, terminating in the security connector to the audio output of an AN/PRC-70

receiver, shall exhibit no more than one error in 105 bits at a 16 KBIT rate with a receiver input

set to 15 dB above the minimum (10dB) SINAD value (see 4.5.19).

3.5.20 Transmitter distortion. The distortion shall be 7% maximum in the FM mode

(see 4.5.20).

3.5.21 Audio processing. The gain compression shall be such that when the audio input is

increased 20 dB above the nominal level (-52 dBm) the input to the respective modulation

circuits shall not increase more than 3 dB (see 4.5.21).

3.5.22 Sidetone. The transmit audio sidetone level shall be within the range of 4 to 11 dB

below the normal receive levels for voice modes and 0 to 7 dB below receive levels for the FSK

and CW modes.

3.5.23 Overall frequency tolerance. The overall frequency tolerance for the Radio Set shall

be less than � 1.66 ppm/yr. Overall tolerance is defined to include the combined effects of initial