Standard C828M - Channel Increase

12. Chaimel Increase
1.
Specifications of Crystal Oscillating Unit
Use the crystal oscillating unit of the size of HC25/U. The fi rst local oscillator
frequency of C828M is based on 8-multipIication system, and the fi rst intermediate
frequency is 22.0 MHz. Therefore, the frequency of the crystal oscillating unit
can be obtained from the following formula:
fr-22.0
fo=
8
2.
fo: Frequency of crystal oscillating unit (MHz)
fr: Wanted transmit/receive frequency (MHz)
Crystal Oscillator Installation Procedures
When the crystal oscillating unit of your desired frequency is reay, take out
the chasis of this transceiver from the case by removing the two case mounting
screws from the rear. For the arrangement of the socket of the crystal oscillat
ing unit, see Fig. 12-1 below.
CRYSTAL LOCATION
oo
CKSE)
OCES)
CKSn)
CKEID
OdOD
CKmD
CKHE)
(ÜöSkD
(UDO
QlilHD
Figure 12-1
3. Frequency Adjustment
The offset oscillator of C828M and the frequencies of the actually loaded Chan
nels have been precisely adjusted. However, if additional Channels are installed,
be sure to perform necessary Channel frequency adjustments. In case that a fre
quency counter is not available, conduct the adjustments according to the follow
ing procedures, using the accessory terminal:
First, connect a 30 to 50/iA amperemeter to the accessory terminal No. 1 and
No. 6 pins.
(a) Align the receiving frequency of your Station with the frequency of your
party's Station. While in reception of the signal from your party's Station, ad-
just the trimmer capacitor in the crystal oscillating circuit so that the connected
amperemeter indicates zero graduation. If the sound is distorted or you hear
- 14 —