Changing The Frequency; Test Conditions - Shure T1 Service Manual

Shure T1 Body-Pack Transmitters

Changing the Frequency

Alignment

Test Conditions

Service Procedures
T1 Series System Operating Frequencies
Group
T
T
T
A
A
A
A
B
B
C
C
The operating frequency of the T1 transmitter may be changed with-
in a specific group by changing the crystal on the pc board. (For Group
information, see the preceding section.) Check the transmitter for proper
operation before attempting to change its operating frequency. After in-
stalling the new crystal, perform the alignment procedures. Then run an
operational test to ensure the transmitter is functioning properly. Finally,
update the label to show the new frequency and letter identification code.
Note: To ensure proper operation, obtain the crystal from Shure and
verify that it operates within the frequency range of the pc board.
Since crystals are marked with their nominal oscillating frequency,
not a letter code, you can use the following equation to determine
the frequency at which a transmitter will operate with a given crystal:
Carrier Frequency = (9  nominal crystal freq. in
The and audio alignments are generally done together, as a
RF
single, continuous procedure. Before beginning, be sure to do the setup
described in the following subsection, "Test Conditions."
The following test conditions apply unless otherwise specified (see
Figure 2):
S
An external 9-volt supply is connected to the battery terminals
(J101 and J102).
S
The Power On/Off switch is off.
S
The Mute switch is set to "Mute."
10
Table 2
Crystal Code Freq. (
V 169.445
AC 170.245
W 171.845
CA 176.200
CC 177.600
CE 182.200
CF 183.600
CG 186.200
CL 192.200
CQ 202.200
CV 208.200
z)
MH
z) –.09
MH
25C1016 (CC)