Charles 7305-14 4W-2W, Руководство пользователя

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Section 730–514–202
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7.4 Front Panel RCV and XMT GN/ATN Switches(Transmission Level Adjustment)
The RCV GN, ATN DIP switches and the XMT GN, ATN DIP switches are used to provide up to 24dB of prescrip-
tion gain or attenuation in 0.1dB increments. See Part 8 for alignment of the receive and transmit voice paths.
7.5 Switch S7 [BON (Build-Out-Network)]
Switch S7 is used to balance out the DC resistance and capacitance of a 2W cable. If the 2W cable is 100 to 250
feet of 26 AWG wire, place S7 in the IN position. If the 2W cable is less than 100 feet of 26 AWG, place S7 in the
OUT position.
Table 3. SIG/TRK, Type I/Type II/Type III, And 2W/4W Station Interface Conditioning With FCC Facility
Code Cross References*
FCC Code Signaling Inter-
face
E&M Interface Switch Positions
face
S3 and S4 S5 S6
TL31M or TC31M Type I (non-looped) Signaling SIG Type I/III 4W
TL11M 2W
TL31E or TC31E Type I (non-looped) Trunk TRK Type I/III 4W
TL11E 2W
TL32M or TC32M Type II (looped) Signaling SIG Type II 4W
TL12M 2W
TL32E or TC32E Type II (looped) Trunk TRK Type II 4W
TL12E 2W
*For type III operation, place switch S5 in the TYPE I/III position.
7.6 Switches On S8 [Receive Equalization Adjustment (RCV EQLR)]
The RCV EQLR switches on S8 are used to provide up to 11dB of prescription equalization (1000 to 2800Hz) in 1
dB increments and up to –1.5dB of low frequency equalization (1000 to 400Hz) in –0.5dB increments. The equal-
izer pivots around 1000Hz so no RCV LEVEL readjustment is required. Condition the receive equalizer according
to Table 6 and the following:
Step Action
1. Determine the 2800Hz and 400Hz losses of the cable with respect to the 1000Hz loss (loss should be
expressed as a positive number, gain as a negative number).
2. Find a line from Table 6 that best matches the facility response and set the switches on S8 as required
by that line. (See EXAMPLE below.)
Note: Choose a response from the table such that the 2800Hz level is less than or equal to the 1000Hz level.
EXAMPLE (For Cable Equalization)
1. 2800Hz cable loss equals 13.1dB.
2. 1000Hz cable loss equals 5.7dB.
3. 400Hz cable loss equals 1.7dB.
4. 2800Hz loss with respect to 1000Hz equals ( + 13.1dB) –( + 5.7dB) = + 7.4dB.
5. 400Hz loss with respect to 1000Hz equals (+ 1.7dB) –( + 5.7dB) = –4.0dB.
6. Choose the line: 2800Hz = + 7.2dB, 400Hz = –4.1dB.