KENNEDY (ELCIT) KB20 ELECTRON YEAR 1974.

The KENNEDY (ELCIT) KB20  ELECTRON  is a 20 inches (50cm) B/W television with 8 programs preselection tuning keyboard and potentiometric search in a drawbar.

The mechanical turret approach to television tuning has been used almost exclusively for the past 60 years. Even though replete with the inherent disadvantages of mechanical complexity, unreliability and cost, such apparatus has been technically capable of performing its intended function and as a result the consumer has had to bear the burdens associated with the device. However, with the " recent "  Broadcast demands for parity of tuning for UHF and VHF channels, the increasing number of UHF and cable TV stations have imposed new tuning performance requirements which severely tax the capability of the mechanical turret tuner. Consequently, attempts are now being made to provide all electronic tuning to meet the new requirements.

 One " " new " " tuning system currently being incorporated in some television receivers uses a varactor tuner which overcomes some of the disadvantages of mechanical turret tuner by accomplishing tuning electronically. As the name indicates, the heart of such a tuner is a varactor diode which is used as a capacitive tuning element in the RF and local oscillator sections. In this system, channel selection is made by applying a given reverse bias voltage to the varactor to change its electrical capacitance. The channel selection biasing can be performed by mechanically or electrically switching approximately 5 or many more preset potentiometers. The problem with such arrangement is that it quite seriously limits the number of channels available to the consumer. Additionally, it suffers from the drawback that all potentiometers require adjusting for the desired channels. The VHF channels are usually factory adjusted while the six UHF channels require on-location adjustment. Moreover, using this arrangement, the only indication--during adjustment--of which channel is selected is by station identification.
Springs component in old tv's tuner :
Most old televisions tuning mechanisms were incorporating coil springs in one form or another for various functions. They can be of the compression type which are wound with spaces between adjacent turns and are intended to be squeezed under pressure : when released they expand to their original form. The mounting springs under record-player turntable units are examples of this type. Alternatively the spring can be of the expanding variety. The coils are wound closely together with adjacent turns touching. The applied tension tends to pull them apart and they exert a contracting force to counteract this and pull the linked components together. In the majority of applications this type is used. Springs often become damaged by being over stretched, or the end loop breaks. More frequently the spring simply becomes detached and disappears. Thus the engineer is faced with the task of finding and fitting a replacement. While it is possible to apply to the makers of the equipment for the right spring this involves delay and of course there is always the problem of identifying the right one out of the many used in the particular mechanism. For this reason many engineers find it more convenient to make their own replacements.

Making a Coil Spring: The operation was quite simple, the equipment needed being a wheelbrace, vice, selection of long screwdrivers with varying diameter shanks and a supply of piano wire of various gauges. The wheelbrace is mounted horizontally in the vice with the wheel uppermost and a screwdriver chosen and inserted into the chuck with the blade foremost. This serves as a mandrel on which the spring can be wound. Because a spring expands slightly in diameter after it is wound the diameter of the screwdriver shank should be a little less than the required inside diameter of the spring. One end of the piano wire should be inserted in the chuck and secured to prevent it coming free. The wheel is then slowly turned and the wire taken up around the screwdriver shank. Keep the wire taut and pull it backward (see Fig. 1) toward the chuck at an angle which keeps the adjacent turns together but does not make a turn ride over the top of its predecessor. When the spring has reached the required length cut the wire and remove the springand screwdriver from the chuck.
As an aid in determining the size of the spring required-especially if the original is lost and there is no pattern to make a comparison with-here are a few observations on the characteristics of coil springs as determined by their dimensions.
Properties of Coil Springs: There are two main properties of a spring, the length to which it can be expanded in comparison to its closed length and its tension or strength in the expanded state. If a coil spring is expanded too far its coils will not return to their original position and the spring is said to be stretched. The amount that a spring can be expanded without becoming stretched is governed by the number of turns and the diameter. The greater the number of turns the less each one has to deviate from its resting position for the complete spring to reach a particular length. Also the greater the diameter the smaller the strain and therefore the more the spring can be expanded. The strength of a spring is related to the gauge of wire and the diameter. A heavy gauge will obviously give greater tension than a lighter one but also a spring with a large diameter will exert less force than a smaller one because as we have seen there is less strain when it is expanded. More force is exerted when the spring is well expanded than when it is nearly closed. If therefore we need a spring that is strong and will stretch a long way we need a large number of turns but not so many that the spring is too long in its closed position. It needs to be of fairly large diameter but as this will make it weaker we must compensate by using a heavy gauge of wire. A weak spring with a long stretch is easily made with thinner wire and a large diameter while a strong spring with a short stretch need have few turns and small diameter. So the various factors are interdependent and although spring design can be quite an exact art-by varying the various parameters-something suitable for the job can usually be made up by judicously estimating the size from the foregoing principles. If a spring has become stretched nothing can be done to restore it by squeezing it up as it has now become a compression spring and the expanded state is its normal one. Rather than winding a completely new spring however the old one can be unwound on a wheelbrace-by reversing the winding process and then rewound tightly. Proper unwinding is essential, not just pulling the spring out straight, because this will produce kinks.
Leaf Springs: From coil springs we turn to leaf springs. These were used as contacts in tuner units and are also were used in the press  button channel selector of the Philips colour TV range and other fabricants. To make a positive contact the leaf spring must be tensioned just right. In the case of the turret tuner the leaf must be so sprung that the contacting stud moves it about a tenth of an inch away from the resting position. If as sometimes happens contact is made without much movement of the leaf there will be little if any pressure and the contact will very likely be intermittent. If on the other hand the leaf is adjusted too far forward it may be caught by the edge of the coil biscuit and crumpled when the turret is rotated.
The set is a hybrid chassis featured  type and it has 4 tubes in power circuits parts.

These sets were collocated in the cheap market allowing so even affordable television sets without concurrence of more expensive other models from bigger brands.

This kind of tv sets are rare by the fact that very few of them were sold.

(Television set kindly donated to me by Marshal Elia Z.)

KENNEDY / ELCIT was a Radio fabrication industry which in the 1953 joined Visiola to produce television sets and other domestic appliances such washing machines and fridge.


ELCIT Was even proprietary of the MAGNADYNE brand which WAS a radio and Television well known brand.

In the 1960 the society was joined and aquired by SEIMART because of a market contraction which landed to GEPI a new society which re - founded ELCIT.

The conglomerate of ELCIT AND SEIMART which was a joint developed by GEPI a government special system invented to "save" industry with "some" difficulties (!!!) was unified.


NOTE:
SEIMART and its conglomerate was even proprietary of brands like:

ETERPHON KENNEDY RAYMOND VISIOLA and DAMAITER.

and

MAGNADYNE +

KENNEDY

and;

The following sub brands were even from the group but were specialized in other fields like
preparing materials, developing parts and other jobs like domestic appliances and even CRT TUBE manufacutring.

NEOHM was a resistor fabricant and was part of the group

Basically the industry group was completely autonomous exept for semiconductors which were coming from other well known brands and manufacturers.

RADSET

VISSET

NEOHM was a resistor fabricant and was part of the group

VITAUT
STAMPLAST
STAMFER

BOBSET
CIRSTA
FRIMAX

MOBFER P

TRAMAX
FINPLAST
VALVEX (CRT TUBES AND TUBES)

ELCIT died in 1998 by typically Italian Industry Destroy culture (and , of course, chinese and turkish (super CRAP) basar !) and all workers and employee landed.......... on the street !!!!!!!!!!!!!

R.I.P. ITALY !