ULTRAVOX (SEMAR) P12 YEAR 1985.

The ULTRAVOX (SEMAR)  P12 is a portable  12 inches (31cm) B/W television with 16 programs manual rotatable program changer and VST electronic tuning semi automatic search.

The tuning system consist in a preset tuner adapted for selecting a desired one out of a plurality of preset channels, comprising: a memory for storing digital data concerning a plurality of channels to be preset, push-buttons/rotatable knob for addressing the memory for reading the digital data of a desired channel, a digital/analog converter for converting the read digital data into an analog signal, a manually operable variable voltage generator to obtain search mode AFC assisted, a write-in/channel select mode selector to store broadcasted transmission in desired program postion by rotatable program positions knob, a switch circuit responsive to the mode selector switchable between the digital/analog converter and the variable voltage generator, a voltage controlled oscillator responsive to the output of the switch circuit, a tuner employing the voltage controlled oscillator as a local oscillator, a comparator for comparing the outputs of the digital/analog converter and the variable voltage generator,

It has a Transistorized horizontal deflection circuits  made up of a horizontal switching or output transistor, a diode, one or more capacitors and a deflection winding. The output transistor, operating as a switch, is driven by a horizontal rate square wave signal and conducts during a portion of the horizontal trace interval. A diode, connected in parallel with the transistor, conducts during the remainder of the trace interval. A retrace capacitor and the deflection yoke winding are coupled in parallel across the transistor-diode combination. Energy is transferred into and out of the deflection winding via the diode and output transistor during the trace interval and via the retrace capacitor during the retrace interval.
In some television receivers, the collector of the horizontal output transistor is coupled to the B+ power supply through the primary windings of the high voltage transformer.

Was one of the last ULTRAVOX Tv sets and last B/W of that type.


ULTRAVOX S.r.l. RADIO TELEVISIONE — Milano, 

Founded in Milan in 1948 with the denomination Ultravox S.r.l of the brothers Sergio and Cino Stanghi, it was dedicated initially to the production of radiophonic apparatus.

 In 1959 the production was moved in a factory to Caronno Pertusella, in province of Varese, where some years later, there was transferred also the seat of the society, which changed in Ultravox S.p.A.

Later  it was specialised in the television sets production, sector in which the mark Ultravox became celebrated and conquered spaces in the market, with the carrying out of a special portable television set completely to transistor with tuner I expel incorporated FM, the model Hummingbird with protection from 6 thumbs of 1969, planned at the designer's Giovanni's Offredi.

In general the models Ultravox were distinguished compared to others, for the very original and futurist design, like the record player Cockchafer of 1970, created always from Offredi. Particular was the models of television sets built with incorporated record player.

In the eighties, the Lombard company, it had interested  a crisis in the market of the electronics that put it in financial difficulties, and therefore in 1982 it was admitted in the list of the societies in field REL, public society for the curing of the enterprises of the electronic sector.

The REL entered into the capital of the Ultravox acquiring 27 % it, since in 1981, the company, which was counting 105 employees, recorded losses in the budget accumulated 1970, piling up to 926 million lire. The accounts improved in the following years since the turnover passed 2,4 milliards from 1982 to 36 in 1987, year in which after years of losses it reached a profit of budget.

In 1988 together with the REL there acquired the control of Emerson of Florence, company television sets producer. They were noticed the mark of the society and the factory of Siena in resort It isolates of Arbia, when the Ultravox was constituting Siena S.p. A. The Sienese factory was reactivated and there was guided the production of television sets and videotape recorders with the marks Ultravox and Emerson.

In the nineties, the company was swept away by a new crisis, which was heavier than that one that struck it on the antecedent decade.

In 1993 it was forced the factory of Caronno Pertusella to close and subsequently it went to checked administration. To go out of this situation, in the capital of the Ultravox there intervened the Bank Mountain of the Paschi of Siena, with a financing for 8,5 milliard lires.

The Sienese factory remained active only with his 200 employees, and the Ultravox was taken from the Holding company Galaxis, German financial society that was checking the Galaxis, company decoder producer for the reception of satellite TV. Initially the Tuscan society unwound the list of Italian distributor for the Galaxis, then later on it specialised in the production of the decoder. Under the new property the company grew again be in terms of turnover in which of sales, and in 1996, Ultravox became the principal decoder supplier for the television paytv Telepiù (died).

In 1998 the Sienese company changed social reason in Galaxis Produzione S.p. A., and it was producing television sets, videotape recorders and decoder for pay TV with the marks Ultravox and Galaxis.

In 2000 the Ultravox-Galaxis is forced to the closing for bankruptcy.

RIP ITALY !

ULTRAVOX (SEMAR) P12 CHASSIS 2T/1 INTERNAL VIEW.

Power supply is realized with mains transformer and Linear transistorized power supply stabilizer, A DC power supply apparatus includes a rectifier circuit which rectifies an input commercial AC voltage. The rectifier output voltage is smoothed in a smoothing capacitor. Voltage stabilization is provided in the stabilizing circuits by the use of Zener diode circuits to provide biasing to control the collector-emitter paths of respective transistors.A linear regulator circuit according to an embodiment of the present invention has an input node receiving an unregulated voltage and an output node providing a regulated voltage. The linear regulator circuit includes a voltage regulator, a bias circuit, and a current control device.

In one embodiment, the current control device is implemented as an NPN bipolar junction transistor (BJT) having a collector electrode forming the input node of the linear regulator circuit, an emitter electrode coupled to the input of the voltage regulator, and a base electrode coupled to the second terminal of the bias circuit. A first capacitor may be coupled between the input and reference terminals of the voltage regulator and a second capacitor may be coupled between the output and reference terminals of the voltage regulator. The voltage regulator may be implemented as known to those skilled in the art, such as an LDO or non-LDO 3-terminal regulator or the like.
The bias circuit may include a bias device and a current source. The bias device has a first terminal coupled to the output terminal of the voltage regulator and a second terminal coupled to the control electrode of the current control device. The current source has an input coupled to the first current electrode of the current control device and an output coupled to the second terminal of the bias device. A capacitor may be coupled between the first and second terminals of the bias device.
In the bias device and current source embodiment, the bias device may be implemented as a Zener diode, one or more diodes coupled in series, at least one light emitting diode, or any other bias device which develops sufficient voltage while receiving current from the current source. The current source may be implemented with a PNP BJT having its collector electrode coupled to the second terminal of the bias device, at least one first resistor having a first end coupled to the emitter electrode of the PNP BJT and a second end, a Zener diode and a second resistor. The Zener diode has an anode coupled to the base electrode of the PNP BJT and a cathode coupled to the second end of the first resistor. The second resistor has a first end coupled to the anode of the Zener diode and a second end coupled to the reference terminal of the voltage regulator. A second Zener diode may be included having an anode coupled to the cathode of the first Zener diode and a cathode coupled to the first current electrode of the current control device.
A circuit is disclosed for improving operation of a linear regulator, having an input terminal, an output terminal, and a reference terminal. The circuit includes an input node, a transistor, a bias circuit, and first and second capacitors. The transistor has a first current electrode coupled to the input node, a second current electrode for coupling to the input terminal of the linear regulator, and a control electrode. The bias circuit has a first terminal for coupling to the output terminal of the linear regulator and a second terminal coupled to the control electrode of the transistor. The first capacitor is for coupling between the input and reference terminals of the linear regulator, and the second capacitor is for coupling between the output and reference terminals of the linear regulator. The bias circuit develops a voltage sufficient to drive the control terminal of the transistor and to operate the linear regulator. The bias circuit may be a battery, a bias device and a current source, a floating power supply, a charge pump, or any combination thereof. The transistor may be implemented as a BJT or FET or any other suitable current controlled device.



Power Supply: The examples chosen are taken from manufacturers' circuit diagrams and are usually simplified to emphasise the fundamental nature of the circuit. For each example the particular transistor properties that are exploited to achieve the desired performance are made clear. As a rough and ready classification the circuits are arranged in order of frequency: this part is devoted to circuits used at zero frequency, field frequency and audio frequencies. Series Regulator Circuit Portable television receivers are designed to operate from batteries (usually 12V car batteries) and from the a.c. mains. The receiver usually has an 11V supply line, and circuitry is required to ensure that the supply line is at this voltage whether the power source is a battery or the mains. The supply line also needs to have good regulation, i.e. a low output resistance, to ensure that the voltage remains constant in spite of variations in the mean current taken by some of the stages in the receiver. Fig. 1 shows a typical circuit of the power -supply arrangements. The mains transformer and bridge rectifier are designed to deliver about 16V. The battery can be assumed to give just over 12V. Both feed the regulator circuit Trl, Tr2, Tr3, which gives an 11V output and can be regarded as a three -stage direct -coupled amplifier. The first stage Tr 1 is required to give an output current proportional to the difference between two voltages, one being a constant voltage derived from the voltage reference diode D I (which is biased via R3 from the stabilised supply). The second voltage is obtained from a preset potential divider connected across the output of the unit, and is therefore a sample of the output voltage. In effect therefore Tr 1 compares the output voltage of the unit with a fixed voltage and gives an output current proportional to the difference between them. Clearly a field-effect transistor could do this, but the low input resistance of a bipolar transistor is no disadvantage and it can give a current output many times that of a field-effect transistor and is generally preferred therefore. The output current of the first stage is amplified by the two subsequent stages and then becomes the output current of the unit. Clearly therefore Tr2 and Tr3 should be current amplifiers and they normally take the form of emitter followers or common emitter stages (which have the same current gain). By adjusting the preset control we can alter the fraction of the output voltage' applied to the first stage and can thus set the output voltage of the unit at any desired value within a certain range. By making assumptions about the current gain of the transistors we can calculate the degree of regulation obtainable. For example, suppose the gain of Tr2 and Tr3 in cascade is 1,000, and that the current output demanded from the unit changes by 0.1A (for example due to the disconnection of part of the load). The corresponding change in Tr l's collector current is 0.1mA and, if the standing collector current of Tr 1 is 1mA, then its mutual conductance is approximately 4OmA/V and the base voltage must change by 2.5mV to bring about the required change in collector current. If the preset potential divider feeds one half of the output voltage to Tr l's base, then the change in output voltage must be 5mV. Thus an 0.1A change in output current brings about only 5mV change in output voltage: this represents an output resistance of only 0.0552.

GENERAL BASIC TRANSISTOR LINE OUTPUT STAGE OPERATION:

The basic essentials of a transistor line output stage are shown in Fig. 1(a). They comprise: a line output transformer which provides the d.c. feed to the line output transistor and serves mainly to generate the high -voltage pulse from which the e.h.t. is derived, and also in practice other supplies for various sections of the receiver; the line output transistor and its parallel efficiency diode which form a bidirectional switch; a tuning capacitor which resonates with the line output transformer primary winding and the scan coils to determine the flyback time; and the scan coils, with a series capacitor which provides a d.c. block and also serves to provide slight integration of the deflection current to compensate for the scan distortion that would otherwise be present due to the use of flat screen, wide deflection angle c.r.t.s. This basic circuit is widely used in small -screen portable receivers with little elaboration - some use a pnp output transistor however, with its collector connected to chassis.

Circuit Variations:
Variations to the basic circuit commonly found include: transposition of the scan coils and the correction capacitor; connection of the line output transformer primary winding and its e.h.t. overwinding in series; connection of the deflection components to a tap on the transformer to obtain correct matching of the components and conditions in the stage; use of a boost diode which operates in identical manner to the arrangement used in valve line output stages, thereby increasing the effective supply to the stage; omission of the efficiency diode where the stage is operated from an h.t. line, the collector -base junction of the line output transistor then providing the efficiency diode action without, in doing so, producing scan distortion; addition of inductors to provide linearity and width adjustment; use of a pair of series -connected line output transistors in some large -screen colour chassis; and in colour sets the addition of line convergence circuitry which is normally connected in series between the line scan coils and chassis. These variations on the basic circuit do not alter the basic mode of operation however.

Resonance
The most important fact to appreciate about the circuit is that when the transistor and diode are cut off during the flyback period - when the beam is being rapidly returned from the right-hand side of the screen to the left-hand side the tuning capacitor together with the scan coils and the primary winding of the line output transformer form a parallel resonant circuit: the equivalent circuit is shown in Fig. 1(b). The line output transformer primary winding and the tuning capacitor as drawn in Fig. 1(a) may look like a series tuned circuit, but from the signal point of view the end of the transformer primary winding connected to the power supply is earthy, giving the equivalent arrangement shown in Fig. 1(b).

The Flyback Period:
Since the operation of the circuit depends mainly upon what happens during the line flyback period, the simplest point at which to break into the scanning cycle is at the end of the forward scan, i.e. with the beam deflected to the right-hand side of the screen, see Fig. 2. At this point the line output transistor is suddenly switched off by the squarewave drive applied to its base. Prior to this action a linearly increasing current has been flowing in the line output transformer primary winding and the scan coils, and as a result magnetic fields have been built up around these components. When the transistor is switched off these fields collapse, maintaining a flow of current which rapidly decays to zero and returns the beam to the centre of the screen. This flow of current charges the tuning capacitor, and the voltage at A rises to a high positive value - of the order of 1- 2k V in large -screen sets, 200V in the case of mains/battery portable sets. The energy in the circuit is now stored in the tuning capacitor which next discharges, reversing the flow of current in the circuit with the result that the beam is rapidly deflected to the left-hand side of the screen - see Fig. 3. When the tuning capacitor has discharged, the voltage at A has fallen to zero and the circuit energy is once more stored in the form of magnetic fields around the inductive components. One half -cycle of oscillation has occurred, and the flyback is complete.

Energy Recovery:
First Part of Forward Scan The circuit then tries to continue the cycle of oscillation, i.e. the magnetic fields again collapse, maintaining a current flow which this time would charge the tuning capacitor negatively (upper plate). When the voltage at A reaches about -0.6V however the efficiency diode becomes forward biased and switches on. This damps the circuit, preventing further oscillation, but the magnetic fields continue to collapse and in doing so produce a linearly decaying current flow which provides the first part of the forward scan, the beam returning towards the centre of the screen - see Fig. 4. The diode shorts out the tuning capacitor but the scan correction capacitor charges during this period, its right-hand plate becoming positive with respect to its left-hand plate, i.e. point A. Completion of Forward Scan When the current falls to zero, the diode will switch off. Shortly before this state of affairs is reached however the transistor is switched on. In practice this is usually about a third of the way through the scan. The squarewave applied to its base drives it rapidly to saturation, clamping the voltage at point A at a small positive value - the collector emitter saturation voltage of the transistor. Current now flows via the transistor and the primary winding of the line output transformer, the scan correction capacitor discharges, and the resultant flow of current in the line scan coils drives the beam to the right-hand side of the screen see Fig. 5.

Efficiency:
The transistor is then cut off again, to give the flyback, and the cycle of events recurs. The efficiency of the circuit is high since there is negligible resistance present. Energy is fed into the circuit in the form of the magnetic fields that build up when the output transistor is switched on. This action connects the line output transformer primary winding across the supply, and as a result a linearly increasing current flows through it. Since the width is
dependent on the supply voltage, this must be stabilised.

Harmonic Tuning:
There is another oscillatory action in the circuit during the flyback period. The considerable leakage inductance between the primary and the e.h.t. windings of the line output transformer, and the appreciable self -capacitance present, form a tuned circuit which is shocked into oscillation by the flyback pulse. Unless this oscillation is controlled, it will continue into and modulate the scan. The technique used to overcome this effect is to tune the leakage inductance and the associated capacitance to an odd harmonic of the line flyback oscillation frequency. By doing this the oscillatory actions present at the beginning of the scan cancel. Either third or fifth harmonic tuning is used. Third harmonic tuning also has the effect of increasing the amplitude of the e.h.t. pulse, and is generally used where a half -wave e.h.t. rectifier is employed. Fifth harmonic tuning results in a flat-topped e.h.t. pulse, giving improved e.h.t. regulation, and is generally used where an e.h.t. tripler is employed to produce the e.h.t. The tuning is mainly built into the line output transformer, though an external variable inductance is commonly found in colour chassis so that the tuning can be adjusted. With a following post I will go into the subject of modern TV line timebases in greater detail with other models and technology shown here at  Obsolete Technology Tellye !


PHILIPS TDA2549 I.F. amplifier and demodulator for multistandard TV receivers:

GENERAL DESCRIPTION
The TDA2549 is a complete i.f. circuit with a.f.c., a.g.c., demodulation and video preamplification facilities for
multistandard television receivers. It is capable of handling positively and negatively modulated video signals in both
colour and black/white receivers.
Features
• Gain-controlled wide-band amplifier providing complete i.f. gain
• Synchronous demodulator for positive and negative modulation
• Video preamplifier with noise protection for negative modulation
• Auxiliary video input and output (75 Ω)
• Video switch to select between auxiliary video input signal and demodulated video signal
• A.F.C. circuit with on/off switch and inverter switch
• A.G.C. circuit for positive modulation (mean level) and negative modulation (noise gate)
• A.G.C. output for controlling MOSFET tuners.

THOMSON TDA3190 COMPLETE TV SOUND CHANNEL:

The TDA3190 is a monolithicintegratedcircuit in a
16-lead dual in-line plastic package.It performsall
the functionsneededfor the TV soundchannel :
.IF LIMITER AMPLIFIER
.ACTIVE LOW-PASSFILTER
.FM DETECTOR
.DC VOLUMECONTROL
.AF PREAMPLIFIER
.AF OUTPUT STAGE
DESCRIPTION
The TDA3190 can give an output power of 4.2 W
(d = 10 %) into a 16 Ω load at VS = 24 V, or 1.5 W
(d = 10 %) into an 8 Ω load at VS = 12 V. This
performance,togetherwiththe FM-IF sectionchar-
acteristicsof high sensitivity, highAM rejection and
low distortion, enables the device to be used in
almost every type of televisionreceivers.
The device has no irradiation problems, hence no
externalscreening is needed.
The TDA3190 is a pin to pin replacement of
TDA1190Z.
The electrical characteristics of the TDA3190 re-
mainalmost constantover the frequencyrange4.5
to 6 MHz, therefore it can be used in all television
standards (FM mod.). The TDA3190 has a high
inputimpedance,soitcanwork withaceramicfilter
or with a tuned circuit that provide the necessary
input selectivity.
The value of the resistors connected to pin 9,
determinethe AC gain of the audio frequencyam-
plifier. This enablesthe desiredgainto be selected
in relation to the frequency deviation at which the
output stage of the AF amplifier, must enter into
clipping.
CapacitorC8, connectedbetween pins10 and11,
determinesthe uppercutofffrequencyof the audio
bandwidth.Toincreasethebandwidththe valuesof
C8 and C7 must be reduced, keeping the ratio
C7/C8 as shown in the table of fig. 16.
The capacitor connected between pin 16 and
ground, togetherwith the internal resistor of 10 KΩ
forms the de-emphasis network. The Boucherot
cell eliminates the high frequency oscillations
causedbytheinductiveloadandthewiresconnect-
ing theloudspeaker.


ULTRAVOX (SEMAR)  P12  CHASSIS 2T/1 Preset tuner:

 A preset tuner adapted for selecting a desired one out of a plurality of preset channels, comprising: a memory for storing digital data concerning a plurality of channels to be preset, push-buttons/rotatable knob for addressing the memory for reading the digital data of a desired channel, a digital/analog converter for converting the read digital data into an analog signal, a manually operable variable voltage generator to obtain search mode AFC assisted, a write-in/channel select mode selector, a switch circuit responsive to the mode selector switchable between the digital/analog converter and the variable voltage generator, a voltage controlled oscillator responsive to the output of the switch circuit, a tuner employing the voltage controlled oscillator as a local oscillator, a comparator for comparing the outputs of the digital/analog converter and the variable voltage generator, a counter to be reset responsive to the push-button search mode AFC  and to be enabled responsive to the write-in mode output of the mode selector to make a counting operation as a function of the output of the comparator, the output of the counter being loaded as the digital data concerning a channel in the memory, as addressed, a reference oscillator, a frequency comparator for comparing the output of the reference oscillator and the intermediate frequency output of the tuner, a filter for filtering the frequency comparator output to provide a correction control signal to the digital/analog converter, the digital/analog converter being adapted to be corrected for deviation of the intermediate frequency of the tuner as a function of the correction control signal.

 A typical conventional preset tuner such as employed in tv receivers and the like comprises a mechanical preset scheme. For example, such a preset tuner employing variable inductance devices as a tuning element is adapted to preset a plurality of channels by varying the inductance value of the variable inductance devices in association with the manual operation of a tuning knob. Another example of such a tuner using a variable capacitance device such as a variable capacitance diode as a tuning element employs variable resistors adjustable in association with the manual operation of a tuning knob for the purpose of a presetting operation.

 Such preset tuners as described above as employing a variable inductance device, a variable capacitance device and the like require provision of the same number of variable inductance devices, variable resistors and the like as that of presetting channel selection switches, which makes the tuner large in size, with the result that such tuner is disadvantageous particularly in case where such tuner is employed in an indash type portable tv receiver, where the tuner is provided in a limited space.


Accordingly, a principal object of the present invention is to provide an improved preset tuner, wherein the data concerning the local oscillation frequencies corresponding to the respective preset channels is preloaded in a memory in a digital representation format.
Another object of the present invention is to provide an improved preset tuner, which is adapted for implementation by large scale integration integrated circuits.
A further object of the present invention is to provide an improved preset tuner, which is adapted for implementation in an electronic structure rather than mechanical structure.


How AFC Circuit Works in B/W Analog Television Receiver:

Push-Button tuning on u.h.f. while being very convenient often leaves a margin of mistuning, especially after some wear and tear has occurred on the mechanism. Even dial tuning can lead to errors due to the difficulty many people experience in judging the correct point. Oscillator drift due to temperature changes can also cause mistuning. Automatic frequency control (a.f.c.) will correct all these faults. The vision carrier when the set is correctly tuned on u.h.f. is at 39.5MHz as it passes down the i.f. strip. Thus if at the end of the i.f. strip a discriminator tuned circuit is incorporated centred on 39.5MHz the discriminator output will be zero at 39.5MHz and will move positively' one side of 39.5MHz and negatively the other as the tuning drifts. This response is shown in Fig. 1.

If the tuning is not correct then the discriminator output is not zero and if this output is applied to change the reverse bias on a tuning diode mounted in the oscillator section of the u.h.f. tuner it will correct most of the error. Tuning, varicap or varactor diodes-to give them a few of their names-are junction diodes normally operated with reverse bias but not sufficient to bias them into the breakdown region in which zener diodes operate. The greater the reverse bias the lower their capacitance: a typical curve, for the PHILIPS BB105 or STC BA141 tuning diode, is shown in Fig. 2. All diodes exhibit this basic type of characteristic but special diodes have to be used for u.h.f. because they must not introduce any excessive loss into the tuned circuits they control. In other words, just as a coil has to have a good Q so does a varicap diode. Normally, we don't worry about the Q of a capacitor as it is usually very good. However, a tuning diode is not a true capacitor. It has, for example, leakage current so the Q of the diode is a factor which has to be considered. The diode manufacturer however will have considered these points and if you buy a diode specified for u.h.f. use you will have no trouble. These points have been mentioned to clear up any misunderstandings and to show why any old diode won't do.

Basic AFC System
To return to our TV set, if the oscillator frequency is too high then the vision carrier frequency will also be too high and in the simple arrangement shown in Fig. 3 the discriminator will give a negative signal to decrease the bias on the tuning diode thus increasing its capacitance and in turn reducing the oscillator frequency and correcting the error. Note that in this diagram the reverse bias on the diode is applied to its cathode. It is therefore positive with respect to ground so that a negative signal from the discriminator will reduce the positive voltage on the diode thus reducing its bias and increasing its capacitance. In this arrangement the diode is biased somewhere near the mid point of its characteristic by the positive d.c. bias fed into one side of the discriminator. The discriminator thus adds to or subtracts from this d.c. bias.

AFC Loop Gain:
The amount by which the error is reduced depends on the gain of the circuit. An estimate of the gain required must first be made by guessing how much error is likely to be given by your push -buttons or hand tuning: 1MHz would be an outside figure as a tuning error of that magnitude would produce a very bad picture of low definition in one direction and badly broken up in the other. This error should be reduced to about 100kHz to be really unnoticeable, indicating a required gain of ten. In fitting a.f.c. to an existing set some measure- ments should be done as an experiment before finally deciding on the circuit gain. The first thing to do is  to add the suggested discriminator to the i.f. strip. As the circuit (Fig. 4) shows a Foster -Seeley type discriminator is used and with the coils specified and the driver circuit shown it should give ±4V for 0.5MHz input variation.

EXAMPLE of Circuit Description:
The driver stage Tr1 takes a small sample signal from the i.f. strip but this should be large enough to drive Tr1 into saturation. That is to say Tr1 is a limiter stage so that the signal amplitude applied to the discriminator coil L2 stays constant over the normal range of signal levels. Trl is biased at approximately 7mA which, according to the original report ("Simple a.f.c. system for 625 -line TV receivers" by P. Bissmire, PHILIPS Technical Communications, March, 1970), gives the best limiting performance. C1, R14 and R3 damp the stage to prevent oscillation. C2 decouples the power feed and should be close to the circuit. The coil former and can are the normal ones used for TV sets and so should be easily obtainable: the former diameter is 5mm. and length 40mm. and winding details are given in Fig. 5.

The invention being thus described, it will be obvious that the same may be varied in many ways. Such variations are not to be regarded as a departure from the spirit and scope of the invention, and all such modifications as would be obvious to one skilled in the art are intended to be included within the scope of the developed apparates both tubes or transistors.

ULTRAVOX (SEMAR) P12 CHASSIS 2T/1 CRT TUBE A31-510W.

TELEVISION TUBE A31-510W

QUICK REFERENCE DATA

31cm (12in) rectangular direct viewing television tube. A separate safety
screen is not required. Especially for use in portable receivers with push-
through presentation.

A special feature of this tube is its short warm—up time.

Deflection angle 110 deg
Final accelerator voltage max. 15 kV
Neck diameter 20 mm —u-

Light transmission 50 % E

Maximum overall length 233 mm

A legible picture appears within 5 seconds (typ. )

This data should be read in conjunction with
GENERAL OPERATIONAL RECOMMENDATIONS — TELEVISION PICTURE TUBES

HEATER
Vh 11  V
Ah 140 mA
Cathode warm —up time (typ. ) 5 s

OPERATING CONDITIONS

Va2, a4 12 kV
VG3 (focus electrode) control range 0 to 350 V
V  A1 250 V
Vg for visual extinction of focused raster  -35 to -69 V
*Vk for visual extinction of focused raster 32 to 58 V

*For cathode modulation, all voltages are measured with respect to grid.

SCREEN
Metal backedFluorescent colour White
Light transmission (approx. ) 50 %.

Focusing Electrostatic

DEFLECTION Magnetic
Diagonal deflection ‘angle  110 deg
Horizontal deflection angle 99 deg
Vertical deflection angle 80 deg

The deflection eons should designed so that their internal contour is in accordance
with the reference line gauge shown on page 4.



CAPACITANCES:
cg all 7. 0 pF
ck all 3. 0 pF
ca2 a4 m 450 to 900 pF
a2,a4 —B 150 PF

EXTERNAL CONDUCTIVE COATING
This tube has external conductive coating, M, which must be connected to chassis.
and the 'capacitance ‘of this ‘coating to the final anode is used to provide smoothing
for the eht supply.
 The electrical connection to this coating must be made within
the area specified on the tube outline drawing;

RASTER CENTRING

See notes under this heading in ' General Operational Recommendations - Television
Picture Tubes' .

Centring magnet field intensity 0 to 800 A/m
Maximum distance of centre of centering field from reference line 47 mm

Adjustment of the centring magnet should not be such that '3. general reduction in
brightness of the raster occurs.

REFERENCE LINE GAUGE see page 4
MOUNTING POSITION Any

The tube socket should not be rigidily mounted but should have flexible leads and be
allowed to move freely.

This ‘tube is fitted with a pin protector in "order to avoid ‘damage to ‘the glass base
due to bending of the base pins whilst handling the tube.

it is advisable to keep this pin protector on the base until it can be replaced by the
socket after the installation of the tube in any equipment.

TELEVISION TUBE A31-410W

RATINGS (DESIGN MAXIMUM SYSTEM)

Va2 a4 max. (at i=0 a2 a4) (see note 1) 15 kV
Vva2 a4,“ min, 8.5kv
va3 max. 500 V
-Va3 max. 50 V
Va1 max. 350 V
va1 min. 200 V
~vg(pk) max. (see note 2) 350 V
~Vg max. (see note 3) ~ 100 V



Adequate precautions should be taken to ensure that the receiver is protected
from damage which may be caused by a possible high voltage flashover within
the tube. '

Maximum pulse duration 22% of one cycle with a maximum of 1. 5ms

The d. c. value of bias must not be such as to allow the grid to become positive
with respect to the cathode, except during the period immediately after switching
the receiver on or off when it may be allowed to rise to +2. OV. It is advisable to
limit the positive excursion of the video signal to +5V(pk) max. This may be
achieved automatically by the series connection of a 10kohm resistor.

. The metal hand must be earthed by means of the tag provided.

The mounting lugs will not necessarily be in electrical contact with the metal
band.

Weight tube alone (approx. ) 2. 8 kg

ULTRAVOX MOD. DONATELLO 16C YEAR 1967.

The ULTRAVOX MOD. DONATELLO 16C is a portable B/W television with 16 inches screen and completely based on tubes technology.

Tuning is performed with VHF and UHF channel selectors on the right side, and the set doesn't weight much like comparing to others sets like the weight of a  PHILIPS portable models from the same era of time.

The B/W Tubes Television set was powered with a External Voltage stabiliser unit (portable metal box) which relates to voltage regulators of the type employed to supply alternating current and a constant voltage to a load circuit from a source in which the line voltage varies. Conventional AC-operated television receivers exhibit several undesirable performance attributes. For example, under low-line voltage conditions such as those encountered during peak load periods or temporary power brown-outs imposed during times of power shortage, picture shrinkage and defocusing are encountered and under extreme brown-out conditions the receiver loses synchronization with a resultant total loss of picture intelligibility.

On the other hand, abnormally high-line voltage conditions are sometimes encountered, and this can lead to excessive high voltage and X-ray generation. In addition, either abnormally high steady state line voltage conditions or high voltage transients such as those encountered during electrical storms or during power line switching operations may subject the active devices and other components of the receiver to over-voltage stresses which can lead to excessive component failure.

It is a principal object of the present invention to provide a new and improved AC-operated television receiver having greatly improved performance characteristics in the presence of fluctuating power supply voltages.

A more specific object of the invention is to provide an AC-operated television receiver affording substantially undegraded performance under even extremely low-line voltage conditions without excessive high voltage and X-ray generation under even extremely high-line voltage conditions.

Still another and extremely important object of the invention is to provide a new and improved AC-operated television receiver having greatly improved reliability against component failure. Such regulators are frequently provided employing saturable core reactors and condensers connected in circuit...  in such manner as to provide a plurality of variable voltage vectors which vary in different senses, as the line voltage varies, but which add vectorially in such manner that their vector sum remains substantially constant upon variations in line voltage, for providing automatic voltage stabilization of single or multiphase A. C. circuits where the supply voltage and frequency are subject to variation above and below normal value and where the load is subject to variation between normal limits.
voltage stabilization
is automatically effected by the provision of an inductive pilot control device which is adapted to provide two excitation supply voltages for producing excitation or satuation of two magnetic circuits of a reversible booster transformer unit or units and diversion of flux from one magnetic circuit to the other, the booster unit being energized by primary windings from the A. C. supplysystem and being provided with a secondary winding or windings connected between the supply system and the corresponding inain or distribution circuit and in series therewith, through which a corrective boost voltage is
imrorjiiced into the circuit under the influence of the pilot control device, of an amount equal to that of the supply voltage fluctuation which initiated it and appropriate in polarity and direction for restoring the voltage to normal value and providing automatic stabilization of the circuit voltage against supply voltages which fluctuate above and below normal value.

The pilot control device which may be employed singly or may comprise three units or their equivalent when applied to multiphase supply systems comprises a pair of closed magnetic circuits or cores constructed of strip wound magnetic material or stacked laminations, the two
circuits forming a pair being constructed of materials possessing dis~similar magnetic characteristics when jointly energized by identical windings in series or by a collective primary winding, the said magnetic circuits being suitably proportioned to provide equal fluxes when ener-
gized at normal voltage.

The pilot control device is provided with a main and an auxiliary secondary winding or group of windings, the main secondary winding or windings being adapted to provide a voltage representing the difference in the fluxes of the two circuits to which it is jointly associated, while
the auxiliary secondary winding embraces only one circuit, preferably that subject to the least amount of flux variation. Either of the windings consists of two equal sections or in effect a double winding with a center tapping to which one end of the single winding is connected.

The voltage in the single secondary winding of the pilot device becomes directionally additive to that in one half of the tapped secondary winding and substractive in respect to that in the other half. When the supply voltage is normal the voltage provided by the single secondary winding is zero, since there is no difference of flux in the two magnetic circuits, and the two excitation voltages
produced in the halves of the other secondary winding are equal and when connected to the two excitation windings of the booster units, do not produce any diversion of flux between the two circuits or sets of circuits in the magnetic system of the booster transformer unit become equal, and since the series winding on the booster unit is arranged to provide a voltage due to the difference of
the fluxes in its two magnetic circuits or sets of magnetic circuits, no corrective voltage is introduced into the main circuit by the booster. If, however, the supply voltage varies from normal the pilot control device provides a voltage across the one secondary winding due to the difference in the fluxes of the two dis-similar magnetic circuits of which it is comprised, which voltage is combined with thosc in the halves of the other secondary winding to provide two excitation voltages which vary complementarily to each other as the supply voltage fluotuates, and cause a transference of flux between the two
circuits or groups of circuits in the booster unit and automatically provide a corrective boost voltage in the main circuit in which the series winding of the booster transformer is includcd of a value equal to that of the variation in supply voltage which initiated it.
The pilot device may be arranged in various ways, forboth single phase and multiphase operation, as exemplified by the constructions hereinafter more fully described.Similarly, numerous arrangements of the booster transformer unit are possible, some of which are hereinafter described in detail. The booster transformer unit embodies thc principles of the inductive devices described in my co-pending Application No. 411,189, filed February 18, 1954.

As an alternative to the provision of an auxiliary secondary winding on the pilot control device this may be
replaced by an independent or external source of supply,which may be either subject to or independent of supply voltage variation, provided such supply may be arranged with a center tapping if required.

Feed-back arrangements may be employed for providing compensation against voltage drop due to the effects of load in various ways. These are preferably providedon the booster transformer unit and may comprise a current transformer in one or more lines of the main circuit,
the secondary output of the transformer being rectified and arranged to energize an additional excitation winding on the booster transformer unit which in clfect increases the amount of the corrective boost voltage as the load increases.




ULTRAVOX S.r.l. RADIO TELEVISIONE — Milano,

Ultravox was a ' Company Italian manufacturer of consumer electronics .
Founded in Milan in 1948 under the name Ultravox by brothers Sergio e Cino Stanghi, Initially devoted to the production of radios. In 1959 the production was moved to a plant in Caronno Pertusella in the provinces of Varese, A Few years later, was the company's Also Transferred to Headquarters, Which Was Transformed into Ultravox Group.Later in the production of Specialized Televisions, In Which sector to the mark won and Ultravox Became famous , with the creation of a special television Completely portable transistors with built-in FM radio tuner, the model with 6 inches of COLIBRI' screen in 1969, designed by John Offredi designers.In general, the models Ultravox distinguished than others, for the design, very original and futuristic, like the Beetle turntable of 1970, created always by Offredi. There were many models of televisions manufactured with built-in turntable.
In the eighties, the Company, was affected by a crisis That Began in the electronics market in financial Difficulties, and for this reason in 1982 was admitted into the list of Companies Within The REL, a public company for the consolidation of Companies electronic form .
In 1988 together with REL Gained Control of the Emerson of Florence, a manufacturer of Televisions.
The factory was started in Siena was reactivated and the production of TVs and VCRs with Ultravox and Emerson brands. In the same year Ultravox launches on market the new version of Radio-TV model Colibri With 6-inch color CRT display and AM / FM tuner.
The unit participated in the selection of the Golden Compass Award of 1989. In the nineties, the company was Overwhelmed by a new crisis, which effectively was more severe than That hit in the decade before. In 1993 he was forced to close and then Went into bankruptcy. To Overcome this situation, the Bank Monte dei Paschi di Siena intervened in the capital of Ultravox , with funding of 8.5 billion pounds . Then Remained only the Siena active plant with 200 employees ITS, Ultravox was aquired by Galaxis Holding, the holding company controlled the German Galaxis , in manufacturer of set-top boxes for receiving satellite TV.Initially the company served as a distributor for the Italian Tuscan Galaxis, then later he Specialized in the production of decoders.Under the new ownership The company came back to grow both in terms of turnover and sales, and in 1996, Ultravox became the leading provider of pay-TV decoders for Telepiù (Failed).

In 1998 the company changed name to Siena SpA Production ITS Galaxis and produced TV sets, VCRs and cable boxes for pay TV with Ultravox and Galaxis brands.In 2000, Ultravox-Galaxis is forced to close due to bankruptcy. In the 2000-Ultravox Galaxis is forced to close two to bankruptcy.The brand Ultravox  " reappears " on the market in 2007 by a distributor in Campania (Italy) with Autovox another Italian brand. .........................

A good point  on good  old  B/W Televisions.....................

The Sixties was a time of great change for TV. At the start of the decade there were just monochrome sets with valves, designed for 405 -line transmissions at VHF. By the end there was 625 -line colour at UHF, with transistorised chassis that used the odd IC.

The following decade was one of growth. The "space race" had begun in 1957, when the USSR launched Sputnik 1 and terrified the Americans. Thereafter the USA began to spend countless billions of dollars on space missions. This got underway in earnest in the Sixties, with the announcement that America would be going all out to get a man on the moon by the end of the decade. There followed the Mercury series of earth - orbit missions, then the Apollo launches. Success was achieved in 1969. Most of these missions were televised, and in those days anything to do with space was hot stuff. It was inevitable that everyone wanted to have a television set. At the time an average receiver would be a monochrome one with a 14in. tube - there was no colour until 1967. It would cost about 75 guineas. 
TV sets were often priced in guineas (21 shillings) as it made the price look a bit easier on the pocket. Anyway 75 guineas, equivalent to about £78.75 in 2000's currency, was a lot of money then.  For those who couldn't, rental was a good option. The Sixties was a period of tremendous growth for rental TV. 
Much else was rented at that time, even radios, also washing machines, spin driers, refrigerators and, later on, audio tape recorders (no VCRs then). 
For most people these things were too expensive for cash purchase. 
There were no credit cards then. And when it came to a TV set, the question of reli- ability had to be taken into account: renting took care of repair costs. 

TV reliability.........The TV sets of the period were notoriously unreliable. They still used valves, which meant that a large amount of heat was generated. The dropper resistor contributed to this: it was used mainly as a series device to reduce the mains voltage to the level required to power the valve heaters. These were generally connected in series, so the heater volt- ages of all the valves were added together and the total was subtracted from the mains voltage. The difference was the voltage across the heater section of the dropper resistor, whose value was determined by simple application of Ohm's Law. 
As valves are voltage -operated devices, there was no need to stabilise the current. So the power supply circuits in TV sets were very simple. They often consisted of nothing more than a dropper resistor, a half or biphase rectifier and a couple of smoothing capacitors. If a TV set had a transformer and a full wave rectifier in addition to the other components, it was sophisticated!
 As the valve heaters were connected in series they were like Christmas -tree lights: should one fail they all went out and the TV set ceased to function. Another common problem with valves is the cathode -to -heater short. When this fault occurs in a valve, some of the heaters in the chain would go out and some would stay on. Those that stayed on would glow like search- lights, often becoming damaged as a result. Dropper failure could cause loss of HT (dead set with the heaters glowing), or no heater supply with HT present. When the HT rectifier valve went low emission, there was low EHT, a small picture and poor performance all round. CRTs would go soft or low emission, the result being a faint picture, or cathode -to -heater short-circuit, the result this time being uncontrollable brightness. On average a TV set would have twelve to fourteen valves, any one of which could go low -emission or fail in some other way. All valves have a finite life, so each one would probably have to be replaced at one time or another. The amount of heat generated in an average TV set would dry out the capacitors, which then failed. So you can see why people rented! 

The CRT could cause various problems. Because of its cost, it was the gen- eral practice to place its heater at the earthy end of the chain. In this position it was less likely to be overloaded by a heater chain fault. But during the winter months, when the mains voltage dropped a bit, it would be starved of power. This would eventually lead to 'cathode poi- soning' with loss of emission. The 'cure' for this was to fit a booster transformer designed to overrun the heater by 10, 20 or 30 per cent. It would work fine for a while, until the CRT completely expired. At about this time CRT reactivators came into being - and a weird and wonderful collection of devices they turned out to be. Regunned tubes also started to appear. You couldn't do this with the `hard -glass' triode tubes made by Emitron. These were fitted in a number of older sets. Yes, they were still around, at least during the early Sixties.



Developments................... A great deal of development occurred during the Sixties. Many TV sets and radios made in the early Sixties were still hard -wired: the introduction of the printed circuit board changed the construction of electronic equipment forever. The first one was in a Pam transistor radio. PCBs were ideal for use in transistor radios, because of the small size of the components used and the fact that such radios ran almost cold. 
They were not so good for use with valve circuitry, as the heat from the valves caused all sorts of problems. Print cracks could develop if a board became warped. If it became carbonised there could be serious leakage and tracking problems. In addition it was more difficult to remove components from a PCB. Many technicians at that time didn't like PCBs. As the Sixties progressed, transistors took over more and more in TV sets. They first appeared in a rather random fashion, for example in the sync separator stages in some Pye models. Then the IF strip became transistorised. Early transistors were based on the use of germanium, which was far from ideal. 

The change to silicon produced devices that were more robust and had a better signal-to-noise ratio. 
Car radios became fully transistorised, and 'solid-state' circuitry ceased to be based on earlier valve arrangements. Many hi-fi amplifiers had been transistorised from the late Fifties, and all tape recorders were now solid-state. 
Both reel-to-reel and compact -cassette recorders were available at this time. Initially, audio cassette recorders had a maximum upper frequency response of only about 9kHz. 
To increase it meant either a smaller head gap or a faster speed. Philips, which developed the compact audio cassette and holds the patents for the design (which we still use in 2000!) wouldn't allow an increase in speed. Good reel-to-reel recorders had a fre- quency response that extended to 20kHz when the tape speed was 15in./sec. 
This is true hi-fi. In time the frequency response of compact -cassette recorders did improve, because of the use of better head materials with a smaller gap. 
This led to the demise of the reel-to-reel audio recorder as a domestic product We began to benefit from spin-offs of the space race between the USA and the USSR. 
The need to squeeze as much technology as possible into the early computers in the Mercury space capsules used by the USA lead to the first inte- grated circuits. 
This technology soon found its way into consumer equipment. Often these devices were hybrid encap- sulations rather than true chips, but they did improve reliability and saved space. The few chips around in those days were analogue devices.  To start with most UHF tuners used valves such as the PC86 and PC88. They were all manually tuned. Some had slow-motion drives and others had push -buttons. They didn't have a lot of gain, so it was important to have an adequate aerial and use low -loss cable..............................