Shure U2 Service Manual page 19

Shure U2 Hand-Held UHF Transmitter
Tone Key Level Adjustment
Service Procedures
1. Use a dc power supply to apply 2.5 ± 0.01 Vdc to the
battery terminals.
2. No audio is applied to the audio input.
3. Do not use filters on the measuring instrument.
4. The tone key frequency will be approximately 32.768 kHz.
5. Adjust R286 so that a tone key level of -22.8 ±0.1 dBu (56 mV)
is measured at pin 1 of U204. For JB models, this level is
–24.7dBu ±0.1 dBu (45 mV).
18
25B1022 (AG)