ZETRON 025-9581M, Руководство по установке и обслуживанию

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Appendix C: Using a Model 620x in a Model 26-based System
182 025-9581M
• Set jumper JP5 (FFSK Output Range) to the “ TEL ” position, if FFSK transmit
levels cannot be set high enough, move it to the “ PWR ” position and try again
Setting Levels in the Model 620x
The underlying assumption for this entire chapter is that you are adding one or two station
transponder units to a system that is already in existence and functioning properly. This
means that you do not need to set levels for the Model 26 dispatcher unit or for the other
station transponders already in service.
The procedures presented here will guide you through quickly setting the receive and
transmit FFSK levels for the Model 6203 and Model 6204 station transponders that have
just been added to the system. In an effort to promote clarity, the level setting procedures
are presented it two formats. The first set is written for radio-based systems. The second
set is written for wire-line-based systems. In addition, the procedures deal only with the
setting of FFSK levels to ensure reliable communications between the Model 26 and the
station transponder units. A brief procedure for adjusting the voice levels going to the PA
amplifier in the station house is presented
on page 186 .
Equipment for this Procedure
• A small, flat-bladed screwdriver suitable for adjusting the potentiometers on the
transponder board of the Station Transponder Unit
• An oscilloscope, actually you may want two of them, one at the Model 26 location
and one at the Model 6203 location
• For setting levels in a radio-based system, a service monitor is required to check
channel deviation levels
• Again, you will want two of these, a laptop computer or PC with an available serial
port and running serial terminal software to be used for controlling either the Model
26 or any of the Model 6203/Model 6204 units, the settings should be: 9600 baud,
8-bit words, 1 stop-bit, no parity checking, and flow control set to none
• Serial cables (Zetron P/N 709-7208) for connecting between PC and Model 26 and
Model 620x
Note The procedures given here only cover setting the FFSK levels to
ensure reliable data packet communication between the Model 26
dispatcher and the station transponder units. Once this is done,
you still have to adjust the voice audio levels on one or both ends
in order to clearly understand announcements made over the
system.