(1) measuring the high-frequency current to try to use a multimeter current file, as measured buffer stage suitable for 100 or 250MA the stall without applying 50MA file, and the measurement point is important to and connected capacitor 0.01uF tiles to prevent self-excited .
(2) of the inductive element one should pay attention to the polarity of the coil head and tail, the second, as far as possible away from the three to make the adjacent mutually perpendicular.
(3) When repeatedly adjust the resonant circuit and the level current is almost constant, very possible that L the C numerical deviation is too large due to the deviation is too large to have been caused by self-excited.
(4) Disconnect the oscillating crystal, the transmitter power output stage current should be zero, otherwise it should progressively examination to exclude self-excited.
(5) adjust the buffer stage amplifier stage is important to the measuring tube current, must not only to determine accurate or not tuned in the resonant inductor connected to the bulb depending on the brightness than normal value is much greater because the current self-excited, and small Bulb brightness has changed little, and easily burned transistor.
(6) transmitters monitor headphones howling should first check the power supply voltage, transmitter power, power consumption naturally.
(7) the receiver high frequency preamplifier section and put in the audio amplifier section best shield grounding heat sink should be ground in a safe and tube shell insulation.
(8) If the components are intact, welding correct normal quiescent current and can not afford to vibration in the launch of the tube junction and a 10 ~ 51PF capacitor to facilitate the start-up. If not from the vibration, you can replace the crystal with a 1000pF capacitor to replace newcomer bad vibration is crystal.
(9) When the output is always enough belief tube B value and the top-level excitation coil turns small and repeated debugging invalid, the level of the inductor polarity reversed to give it a try.
(10) wound core inductor interturn Do not be too close, so adjust core inductance change slowly and evenly, easy to find the best resonance point. Core with plastic pipe can be added to the rubber band.
(11) debug ideal or not important to a field strength meter indicates prevail, but the length of the field strength meter antenna, the state, the distance from the transmitter near coiled or directly welded to the resonant loop, these are will change the indication value of the field strength meter, rather than the resonant circuit of the transmitter is suddenly changed, therefore its indicated value is relative rather than actual. In short, to follow such a principle, regardless of the field strength meter indicates what value, as long as the field strength meter to adjust the resonant circuit by gradually increased until it stops rising to the shock level should also be slightly returned to Lee oscillation stability.
(12) modulation excessive will cause distortion and even burned down the tubes, but the modulation will waste carrier power to reduce the communication distance. Installation and commissioning
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