, = b-10-3-0,25-22-105 = 33. From the depth of feedback-parallel push-pull stage (1+ / Guo 9) «1 + = 33-0,5 17,5i25 dB.
Therefore, when the battery power is almost possible to give the heat from a common ground source.
New dry-cell batteries, which started to produce our industry this year, designed to power the battery radios. Available in the following five different types of batteries: Battery type combined 54 ASMTSG-5-P is designed for the simultaneous supply of anode and grid circuits; Combination-type battery 65 ANMTS-1,3-P, which can be used to simultaneously supply the heating circuits and the anode; anode battery type 70 AMTSG-5; Two types of batteries makalnyh — 1.28-NVMTS-525-P and 1.28-NVMTS-525.
All battery anode and grid elements are assembled from wafer type and Filament — out of cup.
The batteries assigned to this legend the first number indicates the amount of the rated voltage of the battery freshly accelerated mode with continuous discharge. The letters included in the symbol, are the initial letters of the following words: In the anode, C — mesh, H — bill, the MP-zinc-manganese, VIC. — Air-zinc-manganese, T — wafer design «R — panel (this means that the battery terminals are soldered to the special socket).
The second number (at the end of a symbol or before the letter P) corresponds to the nominal capacity in ampere-hours, which should give the battery, freshly accelerated mode with continuous discharge. We combined battery in the symbol indicates the electrical characteristics of only the anode batteries.
Hitherto battery. only the electrical characteristics obtained when fast discharge mode, which is to a large extent different from the actual mode in which the battery operated in practice. In order to be able to better assess their performance, the new battery shows the duration of the work of the periodic (4 hours); discharge resistance, several times larger than those used at an accelerated rate discharge. For battery-NVMTS 1.28 525-bit value is retained soprotivleniya- same. Adopted discharge duration — 4 hours -primerno corresponds to the average duration of the receiver in normal circumstances.
Electrical characteristics of the battery are shown in the table.
Batteries are operational in the temperature range from + 10 ° to + 40 ° C. Store the battery at low temperatures it is advisable. Batteries, dwells at -40 ° C, after warming completely rebuilt its electrical characteristics. These characteristics remain stable during heating panels up to + 40 ° C. The size and weight of the batteries are shown in Table.
The battery type 70 AMTSG-5 and 1.28-NVMTS .vyvody-525 are made of a flexible insulated wire. Do batteries 1.28 NVMTS-525-P is made in the conclusions: a two pin socket. As for the batteries 54 ASMTSG-5-P and «65-ANTSM-1.3-P, they have outlets displayed on panels with eight slots.
In panels located on the battery 54 ASMTSG-5-n are two. guide notch. In the first position the chips cord coming to the receiver, the legs chips inserted into the sockets, which are designated by white circles, and the second position — in blackened in figure slot. The first position corresponds to the anode voltage of 60 V and — 45 in the second. Filament voltage in either of two positions is the same.
The pin at the socket-type battery 65 ANMTS-1,3-P shown in Fig. 16".
AP3 finger on lamps
Receivers «ARZ-51» and «ARZ-52» can easily translate IA lamps finger-Series powered by batteries.
Fig. 1 is a diagram of «ARZ-51» with a little variation, and Fig. 2 and 3 show the device and installation transient pad. Socket for finger lamps is better to take the ceramic, which are through-holes. In the hole and through the key cap from the evil lamp SB-242 passed the bolt tightening socket and base. Fixing it turns solid and accurate.
Light bulbs replaced 6A10S 1A1P, 6B8S, 1B1P, 6P6S-2P1P.
It is necessary to make the following alterations.
Instead, the power cord connects four-core cable to connect the battery. The first wire (80 in) is soldered to the leg 8 kenotron 6TS5S second (at -80} — to the leg lamp 6P6S 8, the third (-1.2 c) -k switch network and four (1.2 in) -k 7 6B8S leg lamp, a wire coming on this leg of the transformer is disconnected.
Leakage resistance 6P6S grid lamp (Li) sealed off from the chassis and attached to the leg 8 of the same lamp. The resistance of the filter capacitance oscillator capacitor put 120 pF, and the end of the same pro • water, connected to the condenser is transferred to the petal 6 range switch, which is connected fixed capacitor R. 500 pF. Resistance to the screen grid circuit (pin 4) is replaced by someone 22 15 com. Everything else remains the same. The left cartridge slot included grounding wire.
To power the receiver needed a battery anode or ALS-80 ALS-70 and one element of BSN-500 or two elements AP-L-30, connected in parallel.
The wire to battery positive glow, you must include a rheostat 10 th.
A. Bychkov Mikhailovka Stalingrad region.
Awarded to the notch filter, the circuit is shown in Fig. 1, and is used in the antenna circuit broadcast receivers n used to suppress noise having frequencies close to the intermediate frequency of the receiver. It can also be successfully applied in the negative feedback loop of narrow-band selective amplifiers and other devices that require a significant suppression of a very narrow frequency band.
Polling properties of the filter is much better than the usual parallel loop (without resistance I). With the parallel circuit can not achieve significant interference suppression, since the resistance of the resonant circuit decreases due to losses in its elements. With the notch filter in Fig. , but you can get the noise suppression in the 50 — 60" low Q of the circuit.
The current flowing through the resistance creates a voltage drop on it. With proper choice of the quantity I can ensure that the voltage at the resonance frequency will be equal in magnitude and opposite in phase to the voltage drop at the capacitor C3. Then the voltage at the output terminals of the filter equal to the sum of the voltages will be zero.
The higher the Q-factor inductors 0 I. At the frequency, the greater will rolloff frequency response. Therefore, the value should be selected so as to ensure the highest quality factor of G0 at the frequency Introducing the notation C] = C2 = C and COP obtain formulas:
From the value of the coefficient k depends rolloff frequency response. If you want to maximize the slope characteristics, the coefficient values are selected according to the table provided.
Table k zone 0.1 -0.07 Points
100 — 200 0,05-0,03
However, when such small znaeniyah decreases the value of P (as seen from the formula (2) and the filter when operating in a high-resistance circuit markedly shunts useful signals with frequencies above / 0. Therefore, the data table can only be used for a filter operating in the low impedance circuit. In all Otherwise, should be taken & = 1, since in this case F has a maximum at a given value. The efficacy of the filter plug to a large extent depends on the accuracy of selection of resistance R. If you want to get a significant inhibition, it is advisable to carry out p as variable resistance, making it easier to fine-tune the filter.
Calculate the filter to suppress the interfering signal at a frequency of 460 to. Resistance R should be as large as possible.
Selecting a specific frame structure called the core, determined experimentally, that the quality factor for the maximum / — 460 kHz can be obtained, for example, for L = 240 mH, Qo = 130 (measured).
Assuming that P should be large, taking k = 1. Substituting the values obtained in formula (1). Then the formula (2) is determined
Riga M. Schoenberg
When switched off so that the needle M deviated full scale. Then the frame of the device is connected in parallel shunt resistor is selected so that the needle M deviated to half of the scale. CTL in this condition, the current frame is equal to the current flowing through. Consequently, the resistance of n frames — You can disable and measure it on the bridge or ohmmeter.
Khabarovsk P. Grigoriev
Resistance measurement frame magnetoelectric microammeter, battery flashlight E shunt resistance and WAN switch.
When measuring the resistance of the scope of the magnetoelectric microammeter in amateur conditions (ohmmeter or device type CT-1)) there is a danger of damage of the device, as the current flowing through the frame, significantly greater than that needed for a full deflection.
I propose a simple and safe way to measure the resistance of the frame. To do this you need to collect chain of device M, the resistance of the frame you want to set, additional
Magnetic tip-off at the TV
During the construction of the TV hams are sometimes faced with such unpleasant phenomenon of aiming AC. Noise may manifest itself in the form of either a raster curving edges, or in the form of a dark horizontal stripes. In the first case there is a magnetic leveling in the second — aiming AC power circuits. In this and in another case, the focus of the received image may be poor. The main source of flooding is the magnetic scattering of the magnetic field of the power transformer. In an effort to reduce the size of the TV, radio amateurs have a power transformer in the vicinity of the tube. The field of the transformer affects the electron beam of kinescope, dismissing him from the desired direction. This results in a distorted pattern. In addition to direct action of the field on the electron beam scattering, this field induces a variable voltage in the focusing coil of the deflection coil, wire resistances rows centering and focusing, which in turn distorts the raster. If the yoke is enclosed in a steel screen, then induced emf can not practically be considered.
The direction of the induced current
Golf scattering throttle filter is similar to the distortion, but this field is much weaker field of the transformer. To reduce interference would be desirable to have a power transformer further from the tube, but it is not always possible without increasing the size of the TV. Possible to reduce the stray field of the power transformer, the transformer having concluded a steel screen. But it turns out that for weakening leakage field transformer is four times the wall thickness of the steel screen should be 3-4 l ‘l. This screen is difficult to make, saying that he turns serious. Possible to reduce the effect of stray fields on the electron beam without using complicated screen. A significant reduction in crosstalk obtained rec appropriate orientation relative to the tube power transformer. Dependence of the field strength of the transformer on the axis of compensating the stray field of the transformer. The degree of compensation of the magnetic leakage field depends on the value of the emf induced in the shorted branch. The magnitude of the induced EMF in turn depends on the resistance of a closed loop, that is, e. On its thickness and width. Fig. 2 shows a closed loop. It can be made of aluminum or copper red thickness of 2-3 mm. The thicker the material loop, the better, because it reduces the resistance to the induced electromotive force and the greater the intensity of the compensating field. The appearance of the induced emf in closed loop is connected to some additional consumption of power is released as heat. This power is low and the practice of it can be ignored. On average, closed loop heating spent 3-5 volts.
Thus, to reduce the interference from the power transformer should have a power transformer at a suitable distance from the kinescope properly oriented with respect to the transformer tube, placed on the transformer shorted compensating coil, transformer positioned under the chassis.
Occurrence IA raster dark horizontal band shows what happens aiming AC power circuits. This usually occurs when the poor performance of the smoothing filter. Increase the capacity and inductance of the smoothing filter. But if it for any reason can not be accomplished, it is necessary to turn the choke filter in a filter plug for a frequency of 50 Hz. For this parallel choke filter attached condenser. At the same time the throttle should be set at 50 Hz. The capacitance value of the parallel capacitor depends on the inductor.
In the case of IA raster two dark horizontal bands are aiming at a frequency of 100 Hz. Choke in this case, you should configure the frequency of 100 Hz. By adjusting the throttle is possible to reduce the voltage of the rectified AC component of three to six times.
Interference AC especially strong in terms of «long-range» reception when watching TV from the bathroom does not ring mains.
When setting up the TV for long-range reception must be correctly positioned transformers and reactors, to compensate for their magnetic fields.
RADIO EXCHANGE OF EXPERIENCE
However, most used tone controls increases the nonlinear distortion of the device. For example, in some tone control rise higher and lower frequencies is performed decreasing depth of negative feedback, this feedback being covered by an output stage amplifier. Reducing the feedback in this case leads to an increase of nonlinear distortion in the output stage are at the edges of a reproduced band and without increase.
Much more sophisticated tone control is a passive four. This brings a four-pole permanent path attenuation at medium frequencies.
it is equal to unity. Moving the potentiometer reduces the amount of feedback ua higher or lower frequencies, thereby increasing the gain at these frequencies.
Moving the potentiometer increases or decreases the signal attenuation at higher or lower frequencies. Adjustment range depends on the attenuation introduced by the four-pole in the midrange. In most cases, the attenuation is 20 dB (the signal decreases ten times) that allows to raise the higher and lower frequency by about 15 dB.
To compensate for the attenuation introduced by the regulator, in the bass amplifier is necessary to introduce an additional gain stage.
From these drawbacks are deep tone control with feedback.
This control is a cascade of colors with deep negative feedback.
The output impedance of the regulator stage tone thanks to the feedback is small. This property can be used when pre-n output amplifier placed on different chassis and controller is a cascade output stage preamplifier. Turning capacity up to 500 pF (capacitance connecting the shield wire) to the frequency response of the path is not affected.
Some of them lack is the need, use a potentiometer with a tap from the middle point, method of manufacturing such a withdrawal was described in the journal «Radna» (1950, № 2, p. 31).
The output impedance of the cascade, followed by a tone control is included, it should be small (about ten kilohms). This condition is fulfilled automatically if used in a cascade transistor 6N8S.
Eating a low-voltage soldering iron
For low-voltage supply (15-25) soldering power, HS 50-60 from the network, temporary voltage in instead, I use the transformer block paper capacitors with a total capacity of 12-16 schfl series with the winding of the soldering iron:
The advantage of this is the ease of soldering performance reel winding need only one or two layers of wire.
B. Kazhinsky, M. login is not a lot of free blade hydraulic system MI login. Fig. 1 shows a kinematic diagram of this engine. To the head 3 two crankshaft crank valovsharnnrno attached horizontal rod 2 vertically set blades 4. Shaft cranks are offset with respect to one another by 120 °. Thus, if one pair of cranks (two rolls) with the rod is in its lowermost position n its lopatkn wholly immersed in water, the two other groups of vanes at the other rods are taken out of the water entirely. If the ‘one pair of cranks, is in the highest position, the group of blades it shtangn entirely removed from the water, and the remaining rods lopatkn half submerged in water.
With a pulley 5 of any one of these trees is removed the total capacity of the entire system of hydro-dvngatelya. GTrn appropriate amount crankshafts n sufficient flow rate can provide hydroelectric energy of a farm PLD farm, located on the banks of the river abounding in a PLD. Power setting less than 1-2 kW can be built on small rivers (at a flow rate of 1 m / n more) to power radios and electric lighting. Hydro mount on the river so that the crankshaft is located across the river, and the horizontal uitangn 2 — along rekn.
For the calibration of transmitters the range 38-40 MHz is convenient to use the two-wire, open-end line length for 8 + 9 m distance between the wires 5 + ■ + 20 cm (Fig. 1, a). Moving along the sensitive indicator, are two adjacent node voltage corresponding to the minimum deviation of the galvanometer needle. Measure the distance between the points (/), is a long wave transmitter X Hmm — 21m.
Indicator can be made to using a sensitive galvanometer and a detector. The resistance is in the range 10 to 100, and someone chosen so as not to overload the passage of the galvanometer voltage antinodes. Instead of a self-made display is very convenient to use a voltmeter VKS-7B. To do this, the input pins of the device attach two rigid copper conductor, which move along the line. Receiver calibration can be performed using a generator GSS-6. Hose with a divider connected to the output of «0-1» generator. Naprizhenne modulated RF applied to the input of the receiver circuit comprising a detector in priemink fall harmonic GSS-6. To determine the frequency at which the receiver is tuned, find two adjacent frequency generator GSS-6 (/ 1/2), harmonics, which are heard in the receiver. The frequency of the receiver is determined by the expression NC
When calibration receiver to beware of the settings on the second channel. R. Svoren
The apparatus for radio-hams
Funkausstellung in Dusseldorf
((50 kHz — 10 MHz and 10-25 MHz). Ensuring the stability of the frequency from 0.01 to
For transmitters and receivers in the bands 145, 435 and 465 MHz oscillatory circuits are made in the form of segments of long lines. These contours are two cylindrical ceramic rod, silver-plated, ground and polished with great accuracy. The rods are fixed to the ceramic holders. At the ends of the rods are copper-plated, 4 mm wide belts for podpayki connecting wires. For coarse adjustment is korotkozamy-kayuschny bridge (also ceramic), internal slot is silvered. Fine-tuning is carried out with the help of variable capacitor (1,8-4,0pf). To ensure the most advantageous compromise between the requirements of maximum quality factor and a high resonance resistance, characteristic impedance circuit is selected to be 215 ohms.
Of the numerous types of variable capacitors for HF and VHF equipment should be noted dual variable capacitor unit capacity from 4.5 to 40 pF each. The capacitors are assembled on HF ceramics of silvered brass plates (rotor — a semi-circular shape). The output from the rotor was done by rubbing the silvered contact. Between packets stator plates both capacitors mounted screen separating them:
As the «news» was advertised dual trimmer assembled on a ceramic plate dimensions 35 X 45 mm. Mr. rotor stator plates are made of silver-plated brass. Between the two capacitors mounted screen. Setting capacitors by using a screwdriver or a special key.
Demonstrated various types of relays, in particular small-size (22X32X34 mm) relay to switch the antenna. This relay has two pairs of contacts maloemkostnye (1.8 pF between the springs and the frame), load capacity up to 30 W per contact pair.
At one of the booths on display in one of the stations (in the range of 80 m) of the German Radio Club. At the other stand — different designs measuring LF and HF generators, VHF transmitters and receivers, tube voltmeters, etc. n. The company, which has developed these patterns produces chassis and kits for self-assembly of various devices by radio amateurs.
Using the GSS-6 at establishing HF transmitters
Standard signal generator GSS-6 commonly used by radio amateurs when setting up the receiver, it may be very useful in establishing amateur transmitters. Here are a few examples of the use of the generator.
Calibration oscillator. As can be any generally located on the coil body, each of which contains 50-100 turns. By varying the frequency of the generator GSS-6, achieve zero beat. Since in this case the frequency of GSC-6 equal to the frequency of the master oscillator, the latter can be determined from the scale generator. Perhaps, however, that zero beat will be formed from a harmonic oscillator. In this case, you must define another (neighboring)! harmonics and a fundamental frequency calculated as the difference between two adjacent harmonic.
Example. Zero heartbeat detected at frequencies 1200-1400 kHz.
The main clock frequency is 1400 — 1200 = 200 kHz. The correctness of calculation can be verified by finding the zero beat with the main clock frequency.
/ Preset oscillating circuit amplifier stage. In this case, we note the response on the testimony tube voltmeter VKS-7. MD setting should be remembered that after switching on the circuit IC and I to the transmitter setting will change somewhat due to the wiring capacitance between the n-duelektrodnyh containers lamps.
Fine-tuning the oscillation circuit
By changing the frequency of the GSS-6 response was observed for the minimum reading of the anode or at the maximum milliamp readings of the voltmeter VKS-7.
Determination of the depth of modulation (Fig. 4).
Contact the generator GSS-6 to the output circuit or an antenna katutsі ‘Coy transmitter by means of the coil / -ev- switch range GSS-6 is set to an intermediate position (between two figures), rec This arrow voltmeter and modulometra unit GSS-6 show » zero. «
We are approaching ice to L3 so that the voltmeter unit GSS-6 showed a 1 uV. At this point, lometr mode will show a signal modulation factor in the transmitter. Les coil contains 30 to 50 turns of PEL-1 0.2.
In all the above dimensions need to use exit «0-1 V» generator GSS-6. lt;
S. Rudolf I
N OC voltage measurement re — ** alternating current universal device type ABO-5 frequency range can be expanded using a remote probe, in which the rectifier element is a semiconductor diode point type DG-C.
Described remote probe to the device type ABO-M collected in the usual way a peak voltmeter (RNS. 1) on a semiconductor diode type DGTS-4. This probe can measure voltage in circuits to high frequency 100 MHz (possibly higher n) in the range of from 0.2 to 20-25 in. The use of other types of diodes (eg DG-TS6, TS7-DG). It will allow some extend these limits to higher voltages.
The entire console is assembled in a small (diameter 38 mm, height 30 mm) PTO karbolit cylindrical body (Fig. 2)) of the quartz resonator removable screw-plugs; it is necessary, Dimo for accession to the prefix circuits with a frequency of 30-50 MHz and over-the plugs in order to avoid increasing the input capacitances. The capacitor C2 must be beziiduk n Zion possible small-size (for example, Tina CSR-2). Output ends, made in the form of two twisted conductors 0.5-0.75 mm vinyl chloride insulation, connected to the terminals Device ABO-5 included in the measurement scale microamperes (60, 300 microamperes PLD 3 mA) for nostoinnogo current.
The unit with the probe best graduating, giving him sine wave frequency of about 100 rings. As a model of the device can be used such as a voltmeter VKS-7B. The dependence of the current measuring device ABO-5 from the high voltage, since two volts and You are a
Kzazhimu GEN ‘
0 and 1 V t GiD — »» K’zazhimu ,, + yi-a"
A. Dolnik above, linear. Therefore, we can define a constant factor for the transfer current (microamps) to the effective value of the voltage (volts).
This ratio is in the range ‘/ ~ th — gt; / z5- By selecting the resistance value of the /? You can set the value of the coefficient, convenient for practical translation. For the scale of 0-3 is necessary to construct a graph. If you change the diode need to re-produce the grading district to determine the coefficient.
Input capacitance probe with screwed plugs is about 7 pF and impedance 2 at frequencies from 1 to 500 kHz — about 16 com; with increasing frequency 7. falls to 7-8 when W Mc com. Availability capacitor enables measurements in circuits with constant component of not more than 200.
Experience with ABO-5M device equipped with such a probe has shown that they can often replace the voltmeter type VCS-7B; This eliminates extra SOURCE-IECN noise and spurious relationships because overall supply chain. Especially convenient when setting up such a device in the high-frequency resonance circuit television n measure the output voltage, as well as an indicator of zero; in the latter case it works well even at frequencies above 1000 MHz.
Instead, the device ABO-5 can be successfully applied any micro-ammeter with outside dimensions: bottom of the B-10 and moss to the top
Recent radiovystavkn in Western Europe indicate a growing interest for use in the broadcasting equipment of transistors.
On radiovystavk’e in West Germany, many companies exposed compact broadcast receivers and amplifiers transistors.
For our readers interested present one extremely compact amplifier for playback gram-plates (Fig. 1). Its compactness is achieved due to the complete absence of transition and output transformers. The amplifier is assembled on four planar transistors. The output push-pooled cascade used in one arm transistor of the «p-p-p ‘, in the other -» n-p-n «, which allowed rec applied to the base of both transistors in-phase voltage signal to obtain the output opposite-phase currents and voltage without the use of PLD You are a reflex
C5 one of the amateur ^ log has a description of a very compact regenerative receiver. Until now, the regenerator to make the transistor was difficult because of the inability to obtain a smooth approach to the lasing threshold, and therefore more sensitive receiver. The described receiver (Fig. 2) implemented the American radio amateur, and, according to him, has an extremely high sensitivity to weak signals.
Adjustment is made by means of paired variable capacitors. The stator plate block these capacitors should be connected to the terminals’ antenna — the Earth. «
Between the handle and the axis of the capacitors must be installed sleeve of insulating material in order to approach hand had no effect on the setting. Adjusting the feedback is carried out con-
Egt; receivers designed for receiving FM signals, as well as television channels sound node is the most complex frequency detector. Basically a proliferation of two types of detectors: frequency detector with pre-restrictor and the detector relations Khodnev transformer. Dynamic speaker has a resistance of 200 ohms moving coil inserted directly to the district average
Regenerative receiver transistorized capacitor C3. Variable Sotfo-tance /? And serves to adjust the sensitivity, it changes the emitter voltage of the transistor. Handsets have to be taken from the ohmic resistance is not lower than 2000 ohms, chokes Dr and DRG — 1 mlg.
The author recommends that the design of the receiver have the battery as far as possible from the high-frequency part, as well as possible to use more recent district not exposed to long-term storage electrolytic capacitors.
If an outdoor antenna length of 25-35 meters carrying out reception at the same time serving as a stop.
Both detectors have two major drawbacks — it is low efficiency and difficult in the performance of a set of contour coils. The disadvantage is also the need for detectors at the entrance large enough Natochka between the two batteries and interconnected collectors of transistors. Amplifier output power of 150 mW. It is intended for use by crystal pickup.
«Funk Technik» N 21 of 1955
radio remote at 200- 1000 km.
In our conditions for such a receiver should be added to a cascade of high-frequency point-triode type S1G and regenerator apply planar transistor P1E.
Adding the high frequency stage is necessary in order to eliminate the emission of a regenerative stage.
«Radia Electronics *, November 1955
voltage signal. For small signals, limiting noise does not come, that’s all. World Cup benefits nullified. Setting such detectors complex in amateur conditions.
A few years ago, it has been proposed a so-called quadrature frequency detector grid (see. «Radio» № 10 of 1950). Such an FM detector is much presche discriminator, but it also works well only at high signal levels.
An American designer is provided with quadrature detector grid, working equally well as in the strong and weak signals. Its efficiency is so great that when it does not require an intermediate gain stage NCh.Preimuschestvom such a detector is also a possibility of using it in the conventional high-frequency pentode. The only requirement for this lamp is the presence of sharply decreasing the characteristics of the safety net.
When the amplitude of the signal voltage on the control grid, in excess of 1.5, the detector operates as a conventional quadrature detector, whose output 20 is obtained in the low voltage. But he. It can work in drugomrezhime. When the voltage at the output not exceeding 0.4, the detector works as a self-excited generator, tighten the incoming FM signal (in the previous mode, this generation is suppressed by the incoming signal).
For such generation capacity between the protective and the control grid must have a value of at least 0.1 per and Q of the circuit in the circuit of the control grid must be large. For this purpose, the coil and the magnetic core is configured as a tank circuit capacitance is used and the lamp assembly. 1 The proposed detector is recommended for use in the channel single-channel television sound receivers. In the audio channel operate only three lamps.
This detector has another advantage: when the pickup when playing grammzapisi it can be attached to the protective tube grid FM detector. With this inclusion, this lamp is used as an extra gain stage LF. Needless switching is carried out by an open wire from the capacitor to the ground and connect it to the pickup.
.RCA Review", December 1955