Showing posts with label transmitter. Show all posts
Showing posts with label transmitter. Show all posts

Circuit Wireless Infra Red Schematic Diagrams

Circuit Wireless Infra Red schematics Circuit Electronics,



Schematics for Wireless Infra Red Circuit Electronics
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Circuit FM Power RF 88-108 Mhz 30 W " BLF245 " Schematic Diagrams

Circuit FM Power RF 88-108 Mhz 30 W " BLF245 " schematics Circuit Electronics,





Schematics for FM Power RF 88-108 Mhz 30 W " BLF245 " Circuit Electronics
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Circuit Oscillator FM Stereo " IC BA1404 " Schematic Diagrams

Circuit Oscillator FM Stereo " IC BA1404 " schematics Circuit Electronics,

Schematics for Oscillator FM Stereo " IC BA1404 " Circuit Electronics
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Electronics 80 MHz - 108 MHz FM transmitter circuit

Circuit 80 MHz - 108 MHz FM transmitter circuit schematics Circuit Electronics,



FM <a href='http://www.circuitlab.org/search/label/transmitter' title=' transmitter  circuits'>transmitter</a> circuit

FM transmitter or often called fm transmitter uses 2 transistors in this article uses 2 transistors 2n2222. If the fm transmitter is in use voltage supply of 9 volt battery and use an antenna whose length is less than 12 inches, then this fm transmitter will be within FCC limits.


Signals from the microphone in the fm transmitter is reinforced by Q1, Q2 with carrier frequency generator is determined by the C5 and L1. The frequency of the FM transmitter is in the range 80 MHz - 108 MHz. L1 can be made ​​with as many as 24 e-mail wire wrap and 6 wrap. The following is a picture series for the fm transmitter fm transmitter referred to in article 2 of this transistor.



rangkaian fm <a href='http://www.circuitlab.org/search/label/transmitter' title=' transmitter  circuits'>transmitter</a> schematics

 


This fm transmitter antenna is connected to the mid point of the antenna length L1 and preferably between 8-12 inches. FM transmitter is only used for experiment and learning materials are not to be used for day-to-day, because the use of FM transmitter frequency regulated and protected by law may be understandable.


Schematics for 80 MHz - 108 MHz FM transmitter circuit Circuit Electronics
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Electronics AM Transmitter circuit analysis

Circuit AM transmitter circuit analysis schematics Circuit Electronics, AM transmitter circuit analysis

Parts of the transmitter AM:

1. The input signal
The input signal in the form of electrical signals generated by mechanical equipment modifier into electrical vibrations. Tools that generate these signals include a microphone, LPs, and others. Power signals issued by these tools, the amplitude is still too small, so it requires strengthening again.



2. audio amplifier
Audio signal that is still small signal voltage amplitude will be strengthened, so that the resulting stress intensity audio signal is strong. amplifier section can be either audio amplifier or preamp only with the amplifier end.

3. Oscillator circuit
Oscillator circuit is an electronic circuit that functions to produce high vibration. The frequency of the resulting circuit is high because if low, this electrical vibration will not radiate much.
Oscillator which is used in the transmitter is the oscillator RF. RF oscillator is a high frequency generator that serves as a signal carrier. Terms oscillator which is capable of generating both high-frequency equipment. Electronic components that can generate these frequencies is Crystal. Crystals are commonly used in FM transmitter has rangkainan 27MHz output frequency.

4. Buffer amplifier (Buffer)
Buffer serves to insulate the RF oscillator with power amplifier, so the fixed oscillator frequency. In addition, this section also reinforces the amplitude of RF signals.

5. Modulator
Modulator is part of an audio signal / information signal with carrier signal. In AM transmitters, the carrier signal amplitude changes are made in accordance with changes in signal amplitude information.

6. Power amplifier
Served to strengthen the power amplifier before dikirimkam termodulsi signal to the antenna to be transmitted. Type of amplifier used is a class C power amplifier class C power amplifier diplih because of its ability to strengthen the radio frequency (above 20kHz). Transistors are used in this amplifier is the RF power transistor, which has the characteristics of the output power ranged from 1 to 75 watts.

7. equalizer
Power supply is a source of power for the transmitter circuit to operate. At the transmitter equalizer is required with a low level of ripple DC. It is intended to prevent hum.

8. Antenna
Antennas in a transmitter is spearheading the delivery of a radio signal transmitter to a receiver. If the antenna is used at a transmitter not meeting the correct specification, then the results are not expected to be achieved. In addition to the range to be erratic also the possibility of damage to the transmitter circuit due to back pressure from the antenna. When the rod antenna is widely used on aircraft such as the transistor radio, car radio receiver, walky Talky, Handy Talky, and so forth.

How it works series AM transmitters:

This powerful AM transmitters ntuk fairly large, use the tuner 3.587 mhz ceramic resonator and resonator filters are also sold with a value of 5.5 mhz, 7.7 mhz and 10.7 mhz.Jarak transmitter range is approximately 2-4 km. the working principle of this circuit are: filter resonator / ceramic filters generate value from the filter frequency resonator tsb. This frequency is amplified by the transistor can be changed so that t1.frekuensi dpperlukan C7 as a regulator / placement. superimposed sound signal through the audio transformer.frekuensi which awakened by the filter resonator and fed t1 kepenguat to be strengthened further so as to achieve the desired power passed to the antenna. t2 and t3 as a buffer as a final power amp
Schematics for AM transmitter circuit analysis Circuit Electronics
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Electronics USB FM transmitter circuit

Circuit USB FM transmitter circuit schematics Circuit Electronics,
USB to FM <a href='http://www.circuitlab.org/search/label/transmitter' title=' transmitter  circuits'>transmitter</a> circuit

Here's a simple VHF FM transmitter that could be used to play audio files from an MP3 player or computer on a standard VHF FM radio. The circuit use no coils that have to be wound. This FM transmitter can be used to listen to your own music throughout your home. When this FM transmitter used in the car, there is no need for a separate input to the car stereo to play back the music files from your MP3 player.


To keep the circuit simple as well as compact, it was decided to use a chip made by Maxim Integrated Products, the MAX2606 [1]. This IC from the MAX2605-MAX2609 series has been specifically designed for low-noise RF applications with a fixed frequency. The VCO (Voltage Controlled Oscillator) in this IC uses a Colpitts oscillator circuit. The variable-capacitance (varicap) diode and feedback capacitors for the tuning have also been integrated on this chip, so that you only need an external inductor to fix the central oscillator frequency.










USB to fm <a href='http://www.circuitlab.org/search/label/transmitter' title=' transmitter  circuits'>transmitter</a> schematics
USB FM transmitter schematics


It is possible to fine-tune the frequency by varying the voltage to the varicap. Not much is demanded of the inductor, a type with a relatively low Q factor (35 to 40) is sufficient according to Maxim. The supply voltage to the IC should be between 2.7 and 5.5 V, the current consumption is between 2 and 4 mA. With values like these it seemed a good idea to supply the circuit with power from a USB port.


A common-mode choke is connected in series with the USB connections in order to avoid interference between the circuit and the PC supply. There is not much else to the circuit. The stereo signal connected to K1 is combined via R1 and R2 and is then passed via volume control P1 to the Tune input of IC1, where it causes the carrier wave to be frequency modulated. Filter R6/C7 is used to restrict the bandwidth of the audio signal. The setting of the frequency (across the whole VHF FM boadcast band) is done with P2, which is connected to the 5 V supply voltage.


The PCB designed uses resistors and capacitors with 0805 SMD packaging. The size of the board is only 41.2 x 17.9 mm, which is practically dongle-sized. For the aerial an almost straight copper track has been placed at the edge of the board. In practice we achieved a range of about 6 metres (18 feet) with this. There is also room for a 5-way SIL header on the board. Here we find the inputs to the 3.5 mm jack plug, the input to P1 and the supply voltage. The latter permits the circuit to be powered independently from the mains supply, via for example three AA batteries or a Lithium button cell. Inductor L1 in the prototype is a type made by Murata that has a fairly high Q factor: minimum 60 at 100 MHz.











usb to fm <a href='http://www.circuitlab.org/search/label/transmitter' title=' transmitter  circuits'>transmitter</a> pcb layout
Layout PCB USB FM transmitter

 


Take care when you solder filter choke L2, since the connections on both sides are very close together. The supply voltage is connected to this, so make sure that you don’t short out the USB supply! Use a resistance meter to check that there is no short between the two supply connectors before connecting the circuit to a USB port on a computer or to the batteries.


P1 has the opposite effect to what you would expect (clockwise reduces the volume), because this made the board layout much easier. The deviation and audio bandwidth varies with the setting of P1. The maximum sensitivity of the audio input is fairly large. With P1 set to its maximum level, a stereo input of 10 mVrms is sufficient for the sound on the radio to remain clear. This also depends on the setting of the VCO. With a higher tuning voltage the input signal may be almost twice as large (see VCO tuning curve in the data sheet). Above that level some audible distortion becomes apparent. If the attenuation can’t be easily set by P1, you can increase the values of R1 and R2 without any problems.


Measurements with an RF analyzer showed that the third harmonic had a strong presence in the transmitted spectrum (about 10 dB below the fundamental frequency). This should really have been much lower. With a low-impedance source connected to both inputs the bandwidth varies from 13.1 kHz (P1 at maximum) to 57 kHz (with the wiper of P1 set to 1/10).


In this circuit the pre-emphasis of the input is missing. Radios in Europe have a built-in de-emphasis network of 50 μs (75 μs in the US). The sound from the radio will therefore sound noticeably muffled. To correct this, and also to stop a stereo receiver from mistakenly reacting to a 19 kHz component in the audio signal, an enhancement circuit Is published elsewhere in this issue (Pre-emphasis for FM Transmitter, also with a PCB). Author: Mathieu Coustans, Elektor Magazine, 2009


MP3 FM transmitter Parts List


Resistors (all SMD 0805)

R1,R2 = 22kΩ

R3 = 4kΩ7

R4,R5 = 1kΩ

R6 = 270Ω

P1 = 10kΩ preset, SMD (TS53YJ103MR10 Vishay Sfernice, Farnell # 1557933)

P2 = 100kΩ preset, SMD(TS53YJ104MR10 Vishay Sfernice, Farnell # 1557934)



Capacitors (all SMD 0805)

C1,C2,C5 = 4μF7 10V

C3,C8 = 100nF

C4,C7 = 2nF2

C6 = 470nF

Inductors


L1 = 390nF, SMD 1206 (LQH31HNR39K03L Murata, Farnell # 1515418)



L2 = 2200Ω @ 100MHz, SMD, common-mode choke, 1206 type(DLW31SN222SQ2L Murata, Farnell #1515599)



 

Semiconductors



IC1 = MAX2606EUT+, SMD SOT23-6 (Maxim Integrated Products)



 

Miscellaneous



K1 = 3.5mm stereo audio jack SMD (SJ1-3513-SMT



CUI Inc, DIGI-Key # CP1-3513SJCT-ND)



K2 = 5-pin header (only required in combination with 090305-I pre-emphasis circuit)



K3 = USB connector type A, SMD (2410 07 Lumberg, Farnell # 1308875)



Notice. The use of a VHF FM transmitter, even a low power device like the one described here, is subject to radio regulations and may not be legal in all countries.

source [ Link ]

Schematics for USB FM transmitter circuit Circuit Electronics
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Electronics Wireless transmitter microphone circuit

Circuit Wireless transmitter microphone circuit schematics Circuit Electronics,
Wireless <a href='http://www.circuitlab.org/search/label/transmitter' title=' transmitter  circuits'>transmitter</a> microphone circuit

Wireless FM transmitter circuit Microphone Hi Fi using a model-ready transmitters, this is because the buil-up transmitter module has a transmission capability of a stable and very effective to emit 10 mW RF. so that the target of Hi Fi FM Wireless Microphone transmitter circuit Hi Fi can be realized. The series can be seen from the FM transmitter Microphone Wireless Hi Fi transmitter module is that it stands alone with an additional R7, R8 and C6 to produce high-quality RF frequency.





In the series of FM transmitter Microphone Wireless Hi Fi module requires power consumption of a battery 12 VDC. Transmission antenna is directly connected with the circuit module Wireless FM transmitter Wireless FM Microphone Hi Fi.


Wireless <a href='http://www.circuitlab.org/search/label/transmitter' title=' transmitter  circuits'>transmitter</a> microphone circuit schematics

Input section of the circuit transmitter Wireless FM Microphone Hi Fi signals to the modulation of 100mV RMS. A microphone preamplifier with IC TL081 is used to reproduce the signal from the microphone into a signal with 100mV rms level as needed this wireless FM transmitter module. strengthening the signal from the microphone preamplifier circuit in FM transmitter Microphone Wireless Hi Fiini regulated by P1. R1, R2 and C1 in the range of an FM transmitter Microphone Wireless Hi Fi is used to provide supply to the microphone electred used.
Schematics for Wireless transmitter microphone circuit Circuit Electronics
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Schematic Diagram Telephone FM Transmitter

Descrition & Circuit


This project is taken from www.electronics-lab.com.

With some modification, I create my own version of FM Telephone bug complete with stripboard layout.

Theortically, the frequency range is from 88MHz to 94MHz but you may experiment with the coil structure to tune it



Circuit



Strip Board Layout






Parts List


Diode IN4384 4
LED 1
Resistor 12k 1
1k 1
200R 1
Capacitor 470p 1
330p 1
25p 1
12p 1
Transistor A933(PNP) 1
Coil *See note 1

*Coil note

7 or 8 turns of 22AWG(diameter .6mm) around 9/64inch(3.6mm)
drill bit. Antenna using the same wire 22AWG, 5inch long

Picture




Compact!




With antenna!




Put it online!




Get ready to tune your radio!


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6 Watts FM broadcast 87,5-108MHz

The layout of the BFR91-BFR96(S)-2SC1971 6 Watts FM broadcast (87,5-108MHz) Profline
Broadband RF-amplifier has been created with sPRINT Layout v3.0.
You can get a Shareware copy at: http://www.abacom.de
The pcb outline is: 85 x 55 mm (width x height), bitmap resolution is 600dpi.
Use FR-4 double sided photoresist epoxy pcb material for best results.

(*) When printing the layout, be sure to resize it!

Design (C)2005 Rdvv, The Netherlands.
Rework (C)2006 by Helix. The Netherlands.
Intitial 2SC1971 microstripline design (C)2002 Sotiris Papadimitriou/ASPiSYS, Ltd. Greece.
(That should cover it!)

Breedband%20Foto_Radio Transmitter Amplifier 6Watt MicroStripline 2SC1971 2sc1971-microstripline(comp)_Radio Transmitter Amplifier 6Watt MicroStripline 2SC1971 2sc1971-microstripline(pcb)_Radio Transmitter Amplifier 6Watt MicroStripline 2SC1971 2sc1971-microstripline(silk)_Radio Transmitter Amplifier 6Watt MicroStripline 2SC1971

BFR91-BFR96(S)-2SC1971 6 Watts FM broadcast (87,5-108MHz) Profline Broadband RF-amplifier

All component values are drawn on the .comp and .silklayer bitmaps, with the following
exceptions;

1.- mount a ferroxcube bead (3 mm diameter, 5 mm length) over one of the wires of the 56E
    resistor (i.e. the wire wich is connected to the base of the 2SC1971 rf-transistor)
2.- the 1uH and 4.7uH coils are ready-made molded type coils.
3.- resistor values are in Ohms, 0.25watts (carbon or metalfilm).
4.- the 47E adjustable resistor measures 10mm diameter, vertical mount (Piher).
5.- all capacitor are ceramic except the 10nF and 100nF ones, these are multilayer types.
6.- the two trimmer capacitors are 22pF, Green (Philips).
7.- the two 150E resistors (at the collector of the BFR96(S) are mounted vertically.

(I)  make sure to mount the rf-transistor on a appropriate heatsink and use some thermal
     heatsink compound between the flange of the rf-transistor and the heatsink or cabinet!
     (Thermal resistance heatsink at least 6°C/W.)
(II) all parts are soldered directly on the toplayer of the pcb.

NOTE: on several places connect the groundplane (bottomlayer) to the groundplane on the
      toplayer, choose at will.

Happy constructing!

(C)2006 Helix. The Netherlands.

URL  : http://groups.yahoo.com/group/lpfm-pirate_radio/

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RF circuit Amplifier sd1127 transmitter 5Watt

SD1127 RF power transistor 5watt. This transistor circuit amplifier mounts somewhat differently from all the other parts. Turn over the PC board and set the transistor snugly into the large hole and bend the leads over and into
the indicated holes. The leads should be as short as possible without shorting against the transistor case. Solder the three transistor leads. See drawing in the step below.

Now we call for something unusual - soldering the transistor case to the PC board. Run a neat "flow" of solder around the transistor case to the PC board ground plane. The SD1127 power transistor is designed by the manufacturer to be soldered directly to a PC board ground plane for heat sinking and proper VHF performance. This part is different from other metal can transistors in that the case is connected internally to the emitter rather than the collector.

This provides much higher gain at VHF frequencies.

sd1127_RF_circuit_Amplifier 5Watt (SD1127)

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Schematic Diagram Electronic FM Telephone Transmitter Circuit

Electronic FM Telephone Transmitter SchematicThe following schematics design pictures is a circuit diagram FM telephone transmitter that built on a PC board layout which is so small it can simply be fitted within the housing of a telephone creating it an instant pseudo-speak earphone. This circuit diagram FM telephone transmitter components connects in series with telephone line, steals power

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Schematic Diagram Long Range FM Transmitter Circuit

Long Range FM transmitter CircuitThe power output of most of these circuits are very low because no power amplifier stages were incorporated. The transmitter circuit described here has an extra RF power amplifier stage, after the oscillator stage, to raise the power output to 200-250 milliwatts. With a good matching 50-ohm ground plane antenna or multi-element Yagi antenna.

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Circuit transmitter using four transister Schematics




http://www.geocities.com/Eureka/Park/5323

four transister transmitter

sine wave transmitter

4 transistor
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Circuit Integrated Transmit IC for Dual-Band Cellular Phones Schematics

Integrated Transmit IC Dual-Band Phones
The MAX2369 may be a dual-band, triple-mode complete transmitter for cellular phones. The device takes a differential I/Q baseband input and mixes it up to IF through a quadrature modulator and IF variable-gain amplifier (VGA). The signal is then routed to an external bandpass filter and upconverted to RF through an SSB mixer and RF VGA. The signal is additional amplified with an on-board PA driver.

The MAX2369 is meant for dual-band operation and supports TDMA for the PCS band additionally as TDMA and AMPS for the cellular band. the required mode of operation is chosen by loading knowledge on the SPI™/MICROWIRE™-compatible 3-wire serial bus. The MAX2369 then routes the signals to the acceptable ports looking on that band is chosen. The MAX2369 includes 2 RF LO input ports and 2 PA driver ports, eliminating the necessity for external switching circuitry.

The MAX2369 takes advantage of the serial bus to line modes like charge-pump current, high or low sideband injection, and IF/RF gain balancing. it's packaged in an exceedingly tiny (7mm x 7mm) 48-pin QFN package with exposed paddle.
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Circuit Mini FM Transmitter Circuit diagram Schematics

Mini FM Transmitter Circuit diagramMini FM Transmitter Circuit diagram

This ambit is a simple two transistor (2N2222) mini FM transmitter. No authorization is appropriate for this transmitter according to FCC regulations apropos wireless microphones. If powered by a 9 volt array and acclimated with an antenna no best than 12 inches, the mini fm transmitter will be aural the FCC limits. The microphone is amplified by Q1. Q2, C5, and L1 anatomy an oscillator that operates in the 80 to 130 MHz range. The oscillator is voltage controlled, so it is articulate by the audio arresting that is activated to the abject of Q2.

R6 banned the ascribe to the RF section, and it’s amount can be adapted as all-important to absolute the aggregate of the input. L1 and C6 can be fabricated with wire and a pencil. The inductor (L1) is fabricated by ambagious two pieces of 24 barometer cloistral wire, laid ancillary by side, about a pencil six times. Remove the braid you accept formed and alleviate the two coils afar from anniversary other. One of these coils (the bigger attractive of the two) will be acclimated in the catchbasin circuit, and the added can be acclimated in the abutting one you build.

The antenna for mini fm transmitter (24 gauge wire) should be soldered to the coil you made, about 2 turns up from the bottom, on the transistor side, and should be 8-12 inches long. To make C6, take a 4 inch piece of 24 gauge insulated wire, bend it over double and, beginning 1/2″ from the open end, twist the wire as if you were forming a rope. When you have about 1″ of twisted wire, stop and cut the looped end off, leaving about 1/2″ of twisted wire (this forms the capacitor) and 1/2″ of untwisted wire for leads.
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Circuit Electronic Circuit 5 Watt FM Amplifier Schematics

5 Watt FM Amplifier Board
This design is a 2 stage amplifier that has about 17db of gain, suitable for an input of 50 to 100 MW. Its basically a Veronica 5 watt vco transmitter, without the vco.

The transistors are a 2N4427 and a MRF237. Output power is 2.5 to 5 watts, depending on input drive and dc voltage. At 13.7 vdc with 50 MW of drive, the output was 2.5 watts. The maximum dc voltage recommended is about 15-16 volts.

The unit is constructed with copper clad board, a large piece is used as the construction surface and is mounted into a case. Other board material is cut into small pads, then glued to the construction surface for part connections. A heatsink is needed for the both transistors, a small "top hat" style will work for TR1 but TR2 requires a larger heatsink thats attached to the case. This is made from aluminum L stock, a 3/8" hole and a slot is made for TR2 to fit snuggly in. Up to 7-8 watts output is possible with this amp, but for continious duty only 5 watts maximum output is recommended.
5 Watt FM Amplifier Circuit
A fan is required and it is mouted on the case lid, with holes drilled for ventilation. The chokes H1, H2 and H3 are 5 turns of 30 awg wire on a ferite bead and choke H4 is a 330 ohm 1/2 watt resistor with 14 turns of 30 awg with a ferite bead on each end. Ferite beads need to be of type 43 material. The coils L1, L2 and L3 are made of 18 awg tinned wire. A 1.5 amp 3ag fuse is part of the dc power cord assembly. I used BNC coax connectors for input and output, however SO-239 or F type connectors would be fine too.
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Circuit Electronic Circuit NJM2035 Stereo Encoder Schematics

NJM2035 Stereo Encoder Board
This package comes with components and instructions that are needed to build simple but high quality stereo encoder.

The circuit connects to any mono FM transmitter and converts it into HI-FI stereo transmitter. The project can be supplied with as little as 1.2 Volts, up to 3.6 Volts. The circuit also has built-in stereo pre-emphasis to enhance and produce a crystal clear sound. NJM2035 is manufactured by NJR CORPORATION (JRC), a subsidiary of New Japan Radio, a company that is known as the world's best manufacturer of high end professional audio semiconductors.

he stereo encoder consists of three main stages; pre-emphasis, digital encoder and mixer stages.Pre-emphasis stage is achieved by using two 47K resistors and two 1nF capacitors. This helps to eliminate the noise that is produced during the FM transmission of your audio signal.
NJM2035 Stereo Encoder Circuit
Second stage that is built around NJM2035 is a digital encoder. All of its internal blocks except for two audio amplifiers (pins 1 & 14) that act as separators are created using digital circuits. The first digital circuit is a 38KHz oscillator that is generated by using external 38KHz crystal (pin 7), 10pF capacitor (pin 6) and 100pF bypass capacitor (pin 5). Once 38KHz frequency is generated it is then buffered and divided into two 19KHz signals with a phase difference of 180 degrees. Once that is done these two frequencies are connected with two time division MPX digital alternating switchers ,one for each audio channel. Here audio channels are switched between each other with a total frequency of 38KHz. If you would be able to slow this frequency to 1Hz per second you would be able to hear that this all but a trick. During the first half of the second you would hear the left audio channel and during the second half of the second you would hear the right audio channel. Due to the fact that the channels are switched with a fast frequency of 38KHz per second our brain is unable to recognize that these channels are really switched and receives this as a continuous audio signal. At the same time another signal from the 38KHz oscillator is divided by half into 19KHz. This signal is called a PILOT tone because it will help a stereo decoder on the receiver’s part to slice the MULTIPLEX signal (mixed L and R audio channels) and separate them back into left and right audio channels.
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Circuit Electronic Circuit Function Generator Schematics

Function Generator Object
The High Speed Function Generator was published in the professional electronics section of the Aug 1996 issue of Electronics Australia, and has proven to be extremely popular. The kit is no longer available from any of the kit suppliers.

There is a problem with the TTL output when the generator is used on the LOW and MEDIUM frequency ranges AND the MAIN frequency adjust control is set to the lower 15% of it's range. Any significant loading on the TTL output will cause it to osscillate on the positive and negative edges. This is apparently an inherent problem with the MAX038 chip !. The only solution is to buffer the SYNC output of the MAX038 with a 74HC14 schmitt inverter. This can be mounted on a small piece of vero-board along with R10 and a bypass capacitor. Use the other 5 inverters in the package in parallel to provide a high current buffered output. Be sure to connect the supply pins of the 74HC14 directly to pins 15 and 16 of the MAX038.
Function Generator PCB
YES, those electro's are hanging over the edge of the PCB. I didn't have anything else available, and Jaycar was closed !. This one didn't have the TTL output, that was a last minute inclusion in the second prototype that was published, hence the oversight described below.
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