Service manual

Page 4
INSTALLATION - continued
DTMF TONE OUTPUT LEVEL
With the service monitor set up as in the previous test: press a DTMF key on the 805
and adjust potentiometer RV1 (accessible through the upper opening) for 2/3 of the
level that modulation limiting occurs as observed on the service monitor. For instance,
if modulation limiting occurs at 5.0 KHZ, then set RV1 for a DTMF tone modulation of
3.3 KHz. If CTCSS tone is also being transmitted at the same time, set RV1 for a
combined CTCSS + DTMF deviation of 4.0 KHz. Verify that the DTMF tones are not
clipped or distorted as observed on the service monitor oscilloscope.
For other system deviation limits, as in 2.5 KHz systems, utilize the same technique
and 2/3 ratio in adjusting the DTMF and voice modulation levels .
Location of Adjustments
Once the DTMF and voice modulation adjustments have been completed, remove the backing
from the rear panel label included and place the label over the potentiometer adjustment access
area.