Electronic Circuit: VHF Dip Meter Based on Transistors

Radio. - This is one of implementation transistors to build VHF Dip meter in this time. It is only need small component completed to build this project in this time.

Beside we will show you electronic design circuit and component parts need, we also will give you global description about this circuit. So, please enjoy to continue reading this article until finish and get more useful.

Electronic Circuit Design

Image Courtesy of https://www.eleccircuit.com/

Component Parts

• Transistors
• Inductor
• Capacitors
• Resistors
• Variable resistors
• Battery

Description

VHF dip meter based on transistors high voltage generator using NE555 IC for you. According Eleccircuits blog mentioned that this is a simple VHF dip meter circuit.The DIP meter is the frequency meter by use the LC resonance circuit that adjustable until the frequency show peak amplitude. The circuit include variable frequency generator circuit, rectifier and a moving coil meter.

In the oscillator include two transistors T1 and T2. The tuning circuit include C1 and coil Lx this coil will is outside the metal box. When apply the power to circuit, the voltage from the oscillator will be rectifier by diodes D1 and capacitor C2. Then, send signal to P1 that use to adjust meter.

If bring the coil Lx near the others LC circuits, that resonance same the frequency is generated. This LC circuit will pull power from Lx, cause the lower voltage drop across the meter. The adjusting frequency by C1 if the frequency resonance can read frequency by the meter.

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Electronic Design: White / LF Noise Generator Circuit using 741 IC

Radio Circuit. - This is one of implementation of Op-Amp IC 741 to build radio generator or oscillator system. It is only need small component completed to build this electronic circuit that basically component.

The electronic design circuit of White / LF Noise Generator using 741 IC is look like in Figure 1 below. Other component used like resistors, capacitors, and zener diode.

Beside we will show you electronic design circuit and component parts need, we also will give you global description about this circuit. So, please enjoy to continue reading this article until finish and get more useful.

Electronic Circuit Design

Figure 1. Circuit of White / LF Noise Generator using 741 IC (Source: Electronicprojects.org)

Component Parts

• R1 = 470 KΩ
• R2, R5, R8, R9 = 10 KΩ
• R3, R6, R10 = 100 KΩ
• R4 = 4.7 KΩ
• R7 = 1 MΩ
• C1 = 0.47 µF
• C2 = 100 µF/10v
• C3, C6 = 1 µF/16v
• C4 = 0.15 µF
• C5 = 0.015 µF
• C7 = 0.001 µF
• C8 = 100 µF/25V
• IC1, IC2 = 741
• ZD1 = 12V 400mW

Description

The electronic circuit design like in Figure 1 above show you generator circuit using Op-Amp 741 IC. Other component need also that can supply with low voltage DC +12V and ground source to charge this IC and all system component from power supply built. With this electronic design circuit you can produce White / LF noise generator that useful now.

According Electronicprojects blog mentioned that in every musician today is in need of a noise source, particularly those who practice with a group or use a synthesizer. The white noise generator gives an output to be fed to an amplifier. The white noise generated by the 12V zener diode is amplified 200 times along with the noise of the noisy 741 IC (IC1). The output is thus very noisy with plenty of white noise.

The output of IC1 is given to a low pass filter which cuts off high frequencies. Point A is connected to amplifier IC2. The feedback network of IC2 includes a 0.15 µF capacitor which reduces the gain at high frequencies.

The 0.001 µF capacitor at the output of IC2 also loads the output at high frequencies and reduce them. Thus the resultant output has a large amount of low frequency (LF) noise.

A small amount of white noise due to the IC itself is produced at the output, but it can be ignored. Point B is an artificial center point created for IC1 and IC2. Point C is connected to the capacitor which reduce the gain of IC2 at high frequencies..

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Electronic Design: FM Transmitter Circuit Using CD4069 and Varicap Diode Without Coil

Radio Circuit. - This is one of implementation of varicap diode and CD4069 IC to build radio generator or oscillator system. It is only need small component completed to build this electronic circuit that basically component.

The electronic design circuit of FM Transmitter Circuit Using CD4069 and Varicap Diode Without Coil is look like in Figure 1 below. Other component used like resistors, capacitors, and Ceramic crystal filter 10.7 MHz.

Beside we will show you electronic design circuit and component parts need, we also will give you global description about this circuit. So, please enjoy to continue reading this article until finish and get more useful.

Electronic Circuit Design

Figure 1. FM Transmitter Circuit Using CD4069 and Varicap Diode Without Coil (Source: Eleccircuits)

Component Parts

• R1_____________6.8K
• R2_____________10K
• R3_____________1K
• R4_____________1M
• R5_____________100K
• R6_____________1.5M
• Capacitors
• C1, C3__________0.1uF 50V Polyester capacitors
• C2_____________10uF 25V Electrolytic capacitors
• C4_____________100pF 50V Polyester capacitors
• C5_____________100uF 16V Electrolytic capacitors
• C6_____________22pF 50V polyester capacitors
• C7_____________0.001 uF 50V polyester capacitors
• Semiconductors
• IC1____________CD4069
• D1____________ Varicap diode
• Others
• Condenser Micro phone
• Ceramic crystal filter 10.7 MHz

Description

The electronic circuit design like in Figure 1 above show you radio transmitter oscillator circuit using varicap diode and CD4069. Other component need also that can supply with low voltage DC +9V and ground source to charge this IC and all system component from power supply built. With this electronic design circuit you can produce FM transmitter generator that useful now.

According Eleccircuits blog mentioned that in Figure 1 above is RF oscillator circuit which use a inverter IC1/2 and ceramic crystal filter 10.7 MHz to use drive IC1/4 – IC1/6 by through IC1/3.

When inverter in parallel form this impedance output is low thus they can drive directly an antenna.

When output of IC1/4 – IC1/6 are square wave which have much more internal harmonic. The harmonic number 9 of frequency 10.7 MHz (96.3 MHz) will take place at the center of the FM band.

The IC1/1 is audio amplifier which signal from the the micro phone will be amplified and will send to varicap diode. This signal causes the capacitance of the varicap diode changed and make also oscillator frequency changes. Thus its occurs modulation frequency.

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