Pic. 127. Scheme for turning on the sound signal:
1 - sound signal; 2 - mounting block; 3 - relay for turning on the sound signal; 4 - sound signal switch.
C-309 beeps are tone-type electromagnetic signals tuned to a specific sound tone. The main sound frequency of the C-309 signal is 503... 523 Hz.
There is an adjusting screw on the body of the sound signal, which can be used to adjust the strength and frequency of the sound of the signal. If the adjustment does not eliminate wheezing or if the signal is intermittent, then it is necessary to disassemble it and clean the contacts of the breaker located in the signal housing. When assembling the signal, the old gasket should be installed between the membrane and the signal housing so as not to disturb the gap of 1.15±0.05 mm between the core and the armature.
If the signal does not turn on, then check the reliability of the wire connection, the condition of the switch and relay contacts in the mounting block. Clean contacts if necessary.