The Manvel Telephone System is one of the first full duplex ( tow way) communication System, In this type of telephone Network the subscriber has a telephone set, this telephone set consist of magnetic bell, Generator and hand Set, While the exchange consist on single board which is known as F-36 Board, In F-36 Board type of telephone system, the subscriber can’t dial the required subscriber number directly, first he calls the operator and then the operator connects them to the required subscriber.
The F-36 Board has two ports, one is connected to the subscriber, while the other one is connected to the exchange end, Each subscriber which is connected to the exchange has a LED on the control penal of the exchange with a female feeder. When a subscriber wants to call some one, first he generate a signal (voltage) through the generator place in side the subscriber telephone set, this voltage turn ON LED placed against each subscriber number, The operator in telephone exchange connect his hand set to the calling subscriber and take from him the called party number, then the operator send AC voltage towards the called subscriber, due to this voltage the called party telephone set ring up and when he pickup the handset the operator connect his to the calling subscriber, this way a connection establish between the subscriber. Merits of Manvel Telephone Exchange
There are the following main Merits of the Manvel Telephone Exchange,
- It is First full duplex Telephone System
- It has a best sound quality.
- Central battery System.
- Easy to connect to the called party.
- Small & less in weight.
De-Merits of Manvel Telephone Exchange
- In this type of exchange there is less privacy.
- 24 hours Communication can’t be possible.
- Without battery can’t work.
- This system is very costly.
- The installation is much difficult.