Audio Alignment - Shure T2 Service Manual

Audio Alignment (Both Models)
25C1018 (CC)
Shure T2 Vocal Artist Microphone Transmitter
C: Spurious Emissions (
1. Set the spectrum analyzer as follows:
S
Scale: 10 dB/div
S
Start Frequency: 10 MHz
S
Stop Frequency:1 GHz
S
Reference level: 20 dBm
2. Check the level of spurious emissions: All must be at least
44 dB below the carrier level. If necessary, retune C226.
D: Current Drain (
ETSI
1. With a digital multimeter, measure the current drain of the trans-
mitter: it should be less than 35 mA. If it is too high, try detuning
C226, but make sure that the power and spurious response re-
main within specification.
2. Check that 9 Vdc (±0.35 Vdc) is present at the head board +9 V
location (I133 on the audio board).
The audio boards on the
are identical except for the pcb number printed on the board. (These
numbers differ because the boards are made as parts of larger assem-
blies for the two different models.)
The audio board has changed relatively little in the history of the T2.
Two examples of changes are the renumbering of the
used to be D101, and the red, D102) and some slightly different designa-
tions (e.g., 1 used to be
I GN
E: Setup
1. Disconnect the power supply from the T2.
2. Unsolder the test cable.
3. Replace C240 (domestic units) or C242 (
board.
4. Slide the board assembly, battery terminals first, into the test
handle: be sure to align the sides of the assembly with the han-
dle's inner tracks. Alternatively, slide the assembly through the
test ring.
5. Screw the audio test head into the handle or ring. Connect a
-to- cable between the audio analyzer and the test
BNC BNC
head.
6. Reconnect the 9 V power supply to the battery terminals of the
T2.
7. Place the Mic switch in the "On" position. Verify that the green
power (D103) lights steadily.
LED
19
-Approved Models)
ETSI
-Approved Models)
-approved and
FCC ETSI
).
IGND
ETSI
Service Procedures
-approved models
s (the green
LED
units) on the
RF