10.1.14. Sound signals

On the car the set from two voice-frequency signals 22 is established. 3721 and 221. 3721 with electromagnetic vibration system.
In signals the electromagnet with a winding is mounted. The anchor of an electromagnet is connected to a membrane and contacts. At inclusion of signals current passes on a winding and attracts an anchor, and together with it and moves a membrane. Movement of an anchor causes disconnection of contacts. Course of current on a winding stops and the anchor under the influence of elasticity of a membrane comes back to a starting position. At the same time contacts become isolated and on a winding current begins to proceed again, attracting an anchor and a membrane. Fluctuations of a membrane cause sound vibrations.
Signals join the switch under a steering wheel via the relay 113.3747 — 10 or 90. 3747.
Technical characteristics of sound signals
Type..... 22. 3721 and 221. 3721
Rated voltage, In..... 12
Loudness, dB..... 105 — 108
The consumed set current, And..... 15
Maintenance of sound signals
Sound signals are calculated on short-term work therefore it is necessary to avoid inclusion of signals for a long time. If signals sound poorly or only one signal sounds, to remove them from the car, to examine and adjust in the following order:

Fig. 9.43. Sound signal: 1 — the case; 2 — the adjusting screw; 3 — a nut; 4 — the plug




- to establish a technological plate under a nut of 3 (fig. 9.43) of the central bolt and to fix a plate with signals in a vice;
- to connect the rechargeable battery and serially including signals, to establish what of them sounds poorly and is subject to adjustment. Adjustment is carried out by the screw 2;
- to include a signal and to listen to its work. Then, having included both signals, to listen to their collaboration. If necessary to adjust the second signal. Normally adjusted signal has to consume current no more than 7,0 — 7,5 And.