20

Am79D2251

Attenuation Distortion

The attenuation of the signal in either path is nominally independent of the frequency. The deviations

from nominal attenuation will stay within the limits shown in Figure 6. The reference frequency is

1014 Hz and the signal level is –10 dBm0.

Figure 6. Transmit and Receive Path Attenuation vs. Frequency

Minimum transmit attenuation at 60 Hz is 24 dB

Group Delay Distortion

For either transmission path, the group delay distortion is within the limits shown in

Figure 7. The minimum value of the group delay is taken as the reference. The signal level should

be –10 dBm0.

Figure 7. Group Delay Distortion

2

0.6

0

Dual ISLAC Specification

0.65

-0.125

0.125

0

0.80

0.2

Receive path

1

Frequency (Hz)

0

90

150

420

Delay (µS)

Dual ISLAC Specification

(Either Path)

Frequency (Hz)