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Repair
204
025-9368H
4.
The Carrier LED
MUST
follow carrier activity on the channel. It must be lit when carrier is
present and extinguished when carrier is absent. If it is always off, the Model 748 will not
function correctly.
5.
The Carrier and DTMF LEDs are hardware controlled. The drive circuits for these LEDs are also
signal inputs to the microprocessor. When trying to troubleshoot an installation, you can use
these as indicators of what information is being provided to the software of the Model 748.
6.
If the unit is non-operational and the AUX LED on the front panel pulses slowly, contact Zetron
Applications for further assistance.
Summary of Contents for 748
Page 2: ......
Page 68: ...Operation 54 025 9368H Notes...
Page 110: ...Programming 96 025 9368H Notes...
Page 216: ...Feature Set Reference 202 025 9368H Notes...
Page 219: ...Repair 025 9368H 205 MODEL 7XX AUDIO BLOCK DIAGRAM 006 0077A...
Page 225: ...Repair 025 9368H 211 MODEL 7XX CONTROL BOARD 008 9793D Schematic Sheet 1 of 5...
Page 226: ...Repair 212 025 9368H MODEL 7XX CONTROL BOARD SCHEMATIC 008 9793D Sheet 2 of 5...
Page 227: ...Repair 025 9368H 213 MODEL 7XX CONTROL BOARD SCHEMATIC 008 9793D Sheet 3 of 5...
Page 228: ...Repair 214 025 9368H MODEL 7XX CONTROL BOARD SCHEMATIC 008 9793D Sheet 4 of 5...
Page 229: ...Repair 025 9368H 215 MODEL 7XX CONTROL BOARD SCHEMATIC 008 9793D Sheet 5 of 5...
Page 230: ...Repair 216 025 9368H MODEL 7XX CONTROL BOARD 702 9793D Silkscreen...
Page 233: ...Repair 025 9368H 219 MODEL 7XX SINGLE E E CARD 008 9794A Schematic...
Page 234: ...Repair 220 025 9368H MODEL 7XX SINGLE E E CARD 702 9794A Silkscreen...
Page 236: ...Repair 222 025 9368H MODEL 4XB VOICE CARD 008 9236F Schematic...
Page 237: ...Repair 025 9368H 223 MODEL 4XB VOICE CARD 702 9236F Silkscreen...
Page 239: ...Repair 025 9368H 225 MODEL 4XB DIAL CLICK BOARD 008 9242E Schematic...
Page 240: ...Repair 226 025 9368H MODEL 4XB DIAL CLICK BOARD 702 9242E Silkscreen...
Page 254: ...Quick Reference 240 025 9368H Notes...
Page 258: ...Specifications 244 025 9368H...
Page 259: ...Specifications 025 9368H 245...