Product manual

Installation
58 025-9158L
mode, measuring across the Rx inputs of the Model 6 while the Model 26 is transmitting
an FFSK test tone. (See Appendix D starting on page
109.)
The Model 26 FFSK output level for a radio communication interface should be set to the
radio manufacturers specification. It is normally recommended that the data signal
produce a 2.5 kHz deviation for wide band and 1.5 kHz for narrow band on FM or PM
type transmitters.
Use JP10 to aid in obtaining the correct signal level. This jumper can be set for TEL
(wire line systems), POWER (heavily loaded wire line or multiple position systems) or
RADIO (radio systems requiring low levels of input audio).
FFSK POST-RCV
This pot is a secondary, receive level adjustment for the FFSK level. It should be turned
completely counterclockwise (its lowest setting).
2W RCV AND 4W RCV
The appropriate pot should be adjusted for a FFSK receive level of 1.0 VP-P at the FFSK
test point on the rear panel of the Mode 26. If this level cannot be obtained with this pot,
the FFSK POST-RCV pot can be turned to increase this signal. Use a remote Model 6
transmitting an FFSK test tone to produce a receive signal. Be sure that the remote Model
6 has had its transmit level set before you do this. (See Appendix D starting on page
109.)
Before performing this adjustment verify that the receive impedance jumpers have been
properly set (JP9 & JP11). Remember that one Model 26 must have this jumper set for
600Ω impedance (Position A). If there are any other Model 26 positions, their jumpers
should be set to Position B.
COR
This pot is used to adjust the COR detect circuit threshold and needs to be adjusted
whether the RX COR input is being used or not. This pot can usually be set to about its
middle position. The important thing here is that the COR/VOX LED is off when nothing
is connected to the RX COR+ input (JP8 must be in position B and COR configured for
COR, Tx on COR Low in the Communications Mode Menu for this test) and goes on
when it is grounded.
VOX
This pot adjusts the VOX detect circuit and does not need to be adjusted if VOX is not
being used (in which case JP3 should be in the B position = VOX disabled).
The COR/VOX LED is the indicator of what VOX is detecting. It will be on when it
detects channel activity and off when it does not. The VOX pot is like a squelch on a