On the car the complete set from two voice-frequency signals 22 is established. 3721 and 221. 3721 with electromagnetic vibrating system.

In signals the electromagnet with a winding is mounted. The electromagnet anchor is connected to a membrane and contacts. At inclusion of signals the current passes on a winding and draws an anchor, and together with it and moves a membrane. Anchor moving causes disconnection of contacts. Current course on a winding stops also an anchor under the influence of elasticity of a membrane comes back in a starting position. Thus contacts become isolated and on a winding the current starts to proceed again, drawing an anchor and a membrane. Membrane fluctuations cause sound fluctuations.

Signals join the switch under a steering wheel through the relay 113.3747 — 10 or 90. 3747.

Technical characteristics of sound signals

Type..... 22. 3721 and 221. 3721

Rated voltage, В.... 12

Loudness, дБ..... 105—108

Consumed current strength of the complete set, А.... 15

Maintenance service of sound signals

Sound signals are calculated on short-term work, therefore it is necessary to avoid inclusion of signals for long time. If signals sound poorly or one signal sounds only, to remove them from the car, to examine and adjust in a following order:

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

- To establish under a nut 3 (fig. 9.43) the central bolt a technological plate and to fix a plate with signals in a vice;

- To connect the storage 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 hear to its work. Then, having included both signals, to hear to their teamwork. If necessary to adjust the second signal. Normally adjusted signal should consume a current no more than 7,0-7,5 And.