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To service, remove the 1505 from the rack or place on a circuit card extension for access while troubleshooting. 3.5 Power Primary power for the card is a regulated source of 12 Vdc.
4.2 Signal Connections and Card Edge Con- nector Pin Assignment Refer to the schematic and Table 4 (shows the 1505’s pin assignments and has a blank for any customized functions that might be configured) for the appropriate pin number to make connec- tions.
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To maintain a 600 termination, it will be necessary to cre- ate a resistive pad on the output of the 1505 line driver. A similar pad must be installed in each parallel device. This resistive pad creates...
The Tellabs (or equivalent) card cage interface connector pins may have a different numbering scheme than the 1505. Table 4 depicts the card edge pin numbers as shown in the schematic, which is also the same as one type of connec- tor, followed by two alternate numbering schemes as used on other connectors.
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Table 4. Card Edge Connector Pin Assignments (Solder Side) Card Alt #1 Alt #2 Edge Conn Conn Card Alt #1 Alt #2 Edge Conn Conn Function Ch #4 Rx Bal. Line In (-) Ch #4 Rx Mute Ch #4 Rx Bal. Line In (+) Ch #4 Rx UnBal Line In Ch #3 Rx UnBal Line In Ch #3 Rx Bal Line In (+)
6. Theory of Operation 6.1 General The 1505 module uses a low loss, wide band transformer for each channel to interface to the phone line. Gain elements are low noise, low distortion, high gain operational amplifiers for quality performance. Each channel utilizes one...
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6.6 Sum Audio The 1505 has a sum audio input circuit and a sum audio output circuit which allows matrix operation with several modules. This allows the expansion of receive input channels or transmit line channels.
1505 Parts List Part No. Description 012-0085 PCB SUB ASSY 1505MIX/LINE 031-0226 TEXT SPEC 1505 AUD MIX/LD 065-0463 PCB 1505 AUD MIX/LIN DR 071-0566 SCHEMATIC 1505 MIX/LINE D 102-0120 CAP CER 20P 5% 50V S2L 102-0290 CAP CER100P S2L 5% 50V...
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Part No. Description 134-2837 RES RN55D 15.0K 1% 1/4W 134-2967 RES RN55D 12.1K 1% 1/4W 134-3032 RES RN55D 15.8K 1% 1/4W 136-0001 RES COMP 2.7 5% 1/4W 136-0022 RES COMP 150 5% 1/4W 136-0040 RES COMP 4.7K 5% 1/4W 136-0044 RES COMP 10K 5% 1/4W 136-0050 RES COMP 33K 5% 1/4W...
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Part No. Description 286-1766 CONN JUMPER PLUG 286-1772 CONNECTOR 36PIN STRIP TIN 286-1964 TEST POINT YELLOW .055 MNT Part No. Description 286-2011 CONN PCB MODULAR 4PIN HS 299-0303 SWITCH 6PST DIP 318-0246 XFORMER 10K CT-10K CT JP10 JP11 318-0259 XFORMER 600CT-600CT JP12 JP13 425-0178...