Product manual

Setting Voice Audio Output Level to Station PA System
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6. Enter the letter “e” as many times as necessary to exit the programming mode.
Move switch SW1-8 on the transponder motherboard to the OFF position.
Remove the serial cable from the transponder.
Model 26 Receive Sensitivity
Set the Model 26 FFSK Receive sensitivity by performing the following steps. Refer to
Figure 28 for locations and Table 7 for descriptions.
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Setting the Model 26 FFSK receive level:
1. Connect an oscilloscope or DVM at the test point labeled FFSK (TP-6) on the
rear panel of the Model 26.
2. Make initial setting to the receive audio control of the Model 26 based on the
type of wire line system to which it is interfaced.
• 2-wire = turn RCV 4W (R69) fully counterclockwise and RCV 2W (R81)
fully clockwise
• 4-wire = turn RCV 4W (R69) fully clockwise and RCV 2W (R81) fully
counterclockwise
3. Turn FFSK POST RCV (R78) fully counterclockwise and VOX (R31) to its
mid-position.
4. At one of the stations where the Model 6 has already had its transmit levels set,
place the Model 6 in the FFSK Level Set mode to generate a test signal.
5. Note the level of the signal at FFSK (TP-6) on the Model 26 and make the
necessary adjustment.
• If the voltage at FFSK (TP-6) is less than 1.0 Vp-p (0.35 Vrms), turn FFSK
POST RCV (R78) clockwise until it reads 1.0 Vp-p
• If the voltage at FFSK (TP-6)is greater than 1.0 Vp-p (0.35 Vrms), turn
RCV 4W (R69) or RCV 2W (R81) counterclockwise until it reads 1.0 Vp-p
6. Once the level setting is complete, you may remove the test equipment and return
the system to the normal operating mode.
Setting Voice Audio Output Level to Station PA System
It is not intended that the Model 6 station transponder unit directly drive the PA speakers
in the fire station in which they are installed. The PA audio coming from J3-pin 9 and J3-
pin 11 should be routed to an input on the station house PA amplifier.
The audio level sent to those connectors is controlled by the pot R87. Initially this control
is set to its mid-range position, and it may turn out that no further adjustment is required