(Continued. Beginning at No. 1,2,3,4′ 2005)
Instruments based on the radio. Assembly and adjustment of the measuring complex
To configure individual measuring devices and the nodes start after the finalization of the radio and Assembly of these devices It will allow to do without the use of laboratory measuring equipment. It is only necessary when setting up the HS in the calibration of the scales of values of the gain of the transistors and voltage.
First, you configure the led output voltage. Setup is reduced to the selection of a base resistor for the selected transistor. This uses a variable resistor 620 — 750 ohms. To start fully enter the resistor and connect the power Gradually reducing the resistance of the resistor, follow the “behavior” of the led. If you experience very faint glow power off, desolder the variable resistor and measure its value Choose the nearest value and solder into the circuit.
To configure the TOS, you can use the features described here are devices and nodes. Assemble and test the circuit of the receiver of direct amplification. For this purpose, the shift forks are connect the first circuit DV range I to the input of the RF amplifier, the RF amplifier output II connect the RF probe, plug cable RF probe connect with sockets “Star”. Don’t forget: the grounding plug must be inserted all the way to the entrance uzch connected with the output of the pre uzch. Switch toggle switch speaker position connecting directly with the output winding. Connect the power supply and give him the voltage of 220 V. the turn of a knob volume control switch on the complex and set the knob at maximum volume. This should light up the led on the front panel. Turning the knob, check the number of received radio stations and the volume.
To test the operation of the receiver of direct amplification on HF bands required tuned antenna and ground. Make sure the normal work of the receiver of direct amplification on all bands. After that, if the input circuits of the radio before the alteration was not subjected to any manipulation, you should start configuring the TOS. The carrier signals of the received radio stations will be used as the external signal generator. Mixing these signals with the signal HS, the method of zero beating that occurs in the bridge-mixer, you can adjust the HS at all ranges.
Before you start to configure the contours of the TOS, you must make sure it is working. For this complex it is necessary to connect a universal console output Jack of the HS by using short-circuited plugs to connect to the input Jack RF amplifier, to the output socket RF amplifier (I or II) connect the RF probe to the output socket RF probe to enter the plug wire indicator. Install DV range using PD. Plug turn on GS. If the output of the HS will appear high frequency oscillations, will immediately begin to work the led indicator. If the glow is very strong. RF test probe plug to the output socket I RF amplifier and then test the HS in the entire DV range.
Verify that the TOS for the DV range, make sure it is working on all other ranges. Making sure to fully functional GS, disconnect with a fork. Disable universal console. Remove the black background plate, which moves the viewfinder. You will get access to the HS coils and trimmer condensers located on the straps of the drum. The upper range switch connector plug and the antenna input of DV and SV ranges of solder temporary wires to the corresponding slats of the drum. With a fork, install the DV range, the drum with straps is also set to “DV” and tune in to one of the receivable stations. After that the minimum magnetic sound Orient the antenna in space. Turn on the HS. The shorted two-pole plug connect the output of the HS with the output I RF amplifier. The output of the RF amplifier II, connect with the RF probe, the cable which connect to the sockets “Star”.
So you’ve implemented a block diagram of the receiver of direct amplification as a source of external signal. The signal GS is allocated to the resistor 27 ohms. This resistor is selected and the external signal. The mixed signal is amplified by RF amplifier II. is detected, amplified uzch and tapped in the speaker. After connecting RF amplifier and the inclusion of the HS signal of the received station should barely listened to or completely disappear. Knob and try to get the heartbeat moving the reticle scales to the right and to the left from the position corresponding to the setting on the radio. To move the reticle must be extremely slow, otherwise the signal beating will not be heard. Getting the beats, tune in for zero runout signal in the speaker should go away.
Adjusting the frequency of GS and constantly checking her receipt of zero beating, combine both positions of the reticle — position that corresponds to zero beat with the situation tune in the station. Reorientation of magnetic antenna in space to increase signal the receiving radio station to listen simultaneously with the beating, and again adjust the contour generator.
Then go to the reception of radio station in the most high end of the range and the same method to adjust the contour of the GS with the only difference that the setting in this part of the range must be performed using the trimmer capacitor. Return to the long-wave band, tune to a radio station and adjust using the trimmer capacitor the frequency of GS After this check that the frequency of GS frequency of any radio station in the middle of the range. Every time you get a beating with the knob of the output signal amplitude of the HS is necessary to achieve maximum audibility of signal beating.
Tuning variable capacitor should be using dielectric screwdriver. Similarly configured to the contours of all ranges of HS. In this setting the TOS ends.
The main parameters of the TOS:
frequency range 150 kHz to 12 MHz;
peak-to-peak output voltage at the load of 1 kW in the CW mode (average, range) 55 — 150 mV;
100% of THEM in the frequency band 100 Hz — 2500 Hz.
In the process of setting the TOS automatically checks the health of RIO, AP, RF probe, indicator and uzch. After configuring the TOS, check the HRU connect the universal receiver to the complex, HRU output Jack connect to the input Jack RF amplifier, one output Jack RF amplifier type plug RF probe, the output socket RF probe connect it to the input of the indicator. Turn with a fork HRU. Will light the led indicator, signaling the presence of oscillations of the drive. The measured double amplitude signal is 350 mV into 1 kω loads. Disconnect the HRU and the universal console. The volume control is set to the correct position for maximum volume Free of the nest “SV.”, in the connector in the right Central compartment type connector mating with the two-wire cable and jumper plug. In the ninth slot lamp panel plug switch frequency generation. The second plug to enter alternately in the nest № 1 — 7. Each time there will be oscillations of audio frequency and pulse shape.
Return the power switch to position 1. Using the volume start to decrease the sound volume. This first will be an increase in the frequency of the audio signal, and then there was the sound of pure tones. This moment corresponds to the generation of sinusoidal oscillations. The frequency of these oscillations is about 700 Hz. Then repeat, turning the power switch frequency from position 1 to position 7. Every time you install a volume control in the position corresponding to maximum volume and then gradually reducing the level of the input signal GSC, seek pure tone. The frequency of the sinusoidal oscillations will grow up to 1400 Hz in position 7 of the switch.
Diagram of the universal consoles (the resistor values are allocated with the* icon is selected while on the construction site:
SA1 — in p-n-p. SA-2 — in position GSC)
Calibration of scales for a universal console is made with a few (5 — 10 pieces) transistors with known values To within the range of values 10 — 100, the regulated source of DC voltage within the range of 1 — 30 V and the DC voltmeter to the same voltage range
The potentiometer (scale values) 10 kω console is placed to the far right (under the scheme). Toggle switch SA1 to set the desired polarity of the supply. The conclusions of one of the transistors with a known value inserted in the corresponding slots of the panels. The potentiometer 1.5 kOhm put in the lowest position (under the scheme).
The console with the cable connected to the complex.
The power switch frequency is set to the 1 (100 Hz). Free slot “This.” from plugs, toggle switch loudspeaker put in the down position and connect the power supply to the network. With proper transistor GSC should immediately appear fluctuations. Slowly turning the potentiometer 1.5 kOhm, achieve the breakdown of generation. Against the handle pointer of the potentiometer make a paper scale glued to the body consoles, level, and record the value In the first transistor. Replace the reference transistor to another and again, rotate the potentiometer from the leftmost position (on a scale), achieve disruption of oscillations GSC and mark the value at which there is a failure. Thus calibrate full scale, repeating this operation at each point three to five times.
The calibration of the scale of the voltmeter consoles are the reference transistor p-n-p structure with a known value, which in the future will always be used for voltage measurements.
The potentiometer 1.5 kOhm, put in the lowest position (under the scheme). Connect the DC voltmeter to the output terminals of the voltage source. Set the output voltage of about 1 V. the potentiometer 10 kω turn to the left. Connect the box to the complex.
Using the cable with the test leads connect the console with the output terminals of the voltage source. As a rule, GSC immediately starts to work. If this does not happen, it is necessary to somewhat reduce the voltage to that value, unless there is generation. Note at what voltage this happens, and apply to paper scale level, and the voltage value. Increasing the source voltage, tear generation. Note the voltage and record this value against a new mark. Continuing to rotate the potentiometer, again start the generator, make a mark on the scale and an increase in voltage of tear generation Record about this point voltage value, at which there was a breakdown of the oscillations. In this way go through diapazoni voltages up to 30 V. the voltage Level at the output of the source down to zero, the potentiometer back to the left and repeat all over again. Adjust marks. Disconnect the voltage source and a voltmeter. Disconnect the power supply from the network.
For scale calibration of the voltage stabilizing Zener pick up a dozen with the measured values of voltage stabilization from 3 V to 12 V. 13 Install 1 potentiometer , 5 kOhm at the low end of the potentiometer 10 kOhms set to the left position. The socket panel on the front of the console, insert the conclusions of the Zener diode: anode — into the socket of the emitter, the cathode — in socket base. Switch SA1 is put into the “p-n-p”. On the switch frequency (9-pin vacuum tube panel) set the frequency to 100 Hz. Connect a console to the system using the cable and turn on the power supply. After one or two seconds GSC will start to generate oscillations of audio frequency.
Press the SB1 button and slowly rotate the potentiometer 10 kOhm clockwise to the failure of the generation. On the scale of the voltmeter draw a second circle on her mark known value voltage stabilization (East) of the first Zener diode. Set the knob of potentiometer 10 kOhm again to the left, replace the Zener diode, press a button and rotate the potentiometer 10 kω, again get a failure generation. Note on the scale a new value Ist. Thus calibrate the entire scale of values Ist. The universal calibration consoles ends.
R. HAKOBYAN
(To be continued)