25-200 MHz Wireless Frequency counter

This frequency counter has 6 digits and will work from 25MHz up to 200MHz that you don't need to connect it with any wires to your equipment. Wires-interference and drift in the oscillation frequency. This counter use a small pick up coil to probe the oscillation. Just hold the pickup coil a few cm from the main oscillator coil and read the LED. The LED has 6 digits and the resolution is set to 1kHz.

Schematic of Wireless Frequency Counter

The hart of this project is the PIC processor. To this processor is 6 LED display connected. The info on the LED is scanned so only one LED is lightning at a time, but your eyes will see it as all LED are lightning at the same time. I use a sensitive prescaler which divide the signal with 64. The output of the prescaler is then connected to a counter input of the PIC processor.

Prescaler

You can use almost any prescaler on the market in this construction. I have found a prescaler called SP4633. It is a quit good one.

High sensitivity and no self-oscillation. The prescaler use a small pickup coil to probe the RF signal.

The pickup coil is made of a wire with two turns. A small portion of the oscillator signal will be picked up by this coil and amplified in the prescaler. The prescaler will also divide the input frequency with 64 and output the signal to pin 6.

A NPN transistor is buffering the signal and amplify it to square wave shape and then the signal enter the PIC-processor.

PIC-processor

So how does it all work?

Imagin you have a 200MHz oscillator. The prescaler picks up the signal and divide it to 200*10⁶ / 64 = 3.125MHz output signal.

Inside the PIC at RC0 is a 16 bit counter. This counter is first reset and then it counts during 64mS. If the frequency was 3.125000MHz during 64mS, the counter will reach 200.000 which will be presented to the display.

The resolution will be 1kHz which is good enough for a handheld wireless frequency counter. Of course one can make the counting time longer and thereby get more digits, but I seldom need more than 1kHz resolution.


Building and Testing 



It is not a difficult project to build, but before you add the prescaler you should test the counter function. I used a external oscillator for this. See picture at right.

The pic show you a crystal controlled oscillator. I use a 3.579545MHz crystal.



Then I connected the output of the oscillator (pin 9) to the RC0 of the PIC (pin 11).

If I use a 3.579545MHz and it simulate a division by 64 it means that the

LED display should show 3.579.545 * 64 = 229.091MHz.


If you don't have a 3.579545MHz crystal you can use any one from 1-to 15MHz, you will have to calculate so the output frequency is about 1 to 4MHz of the oscillator. Just multiply the frequency with 64 and read the display. Simple way to test the construction.


The 64mS counting time in the processor is set by the software and is based on the crystal frequency at 18.432MHz. If you don't have this crystal you can use any crystal from 10 to 20MHz, but a small change of software must be done. I can help you with this, just mail me.


Download PIC16F870 program (INHX8M format)

fcount.zip 18.432 MHz Crystal - PIC program frequency counter.

fcount2.zip 20.000 MHz Crystal - PIC program frequency counter.



Source

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Stereo Compressor Limiter with Clipper for FM Broadcast

This application circuit is stereo audio compressor limiter with clipper for processing your FM audio signal. Limiter is a device, which weakens loud signals and intensifies silent signals. On its output there is signal with constant level. Signal clipping on the limiter output allows to increase the signal level without exceeding maximum frequency deviation limit 75 kHz. It's very suitable since preemphasis is used.

Be careful if you want to buy any simple compressor/limiter board available on the market! Although a big list of features is mentioned, some of these toys have no signal overshooting protection and have no precise preemphasis with HF clipping option. With these devices it's not possible to keep loud sound AND meet the frequency deviation limit. So there is no reason why to pay for them.

Circuit Schematic:

 Left Channel Schematic

Right Channel Schematic

Printed Ciruit Boards (PCB):

 

Part list:

Left channel:
R1, R3 - 10k
R2 - 1k
R4, R5 - 1M
R6 - 18k
R7, R8, R15-R17, R19 - 33k
R9 - 1M5
R10, R12, R14, R18 - 470R
R11 - 270R
R20, R23, R25 - trimmer 5k
R21 - trimmer 5M
R22 - trimmer 1k
R24 - trimmer 500R

C1 - 4n7 (EU) or 6n8 (USA), plastic
C2 - 470n plastic
C3 - 4n7 plastic
C4 - 330n plastic
C5, C7, C8, C12 - 10n ceramic
C6 - 22n ceramic
C9 - 330p ceramic
C10 - 470p ceramic
C11 - 82p ceramic
C13 - 10u/25V tantalum
C14 - 470u/25V electrolytic
C15, C16 - 220u/10V electrolytic

U1 - TLC272
Q1 - BC557B
Q2 - BF245C
D1, D2 - Red!!! LED diode 5 mm, medium luminance (eg. 200 mcd)
J2 - jumper

Right channel:
R1, R3 - 10k
R2 - 1k
R4, R5 - 1M
R6 - 18k
R8, R15-R17, R19 - 33k
R9 - 1M5
R10, R12, R14, R18 - 470R
R11 - 270R
R20, R23, R25 - trimmer 5k
R22 - trimmer 1k
R24 - trimmer 500R

C1 - 4n7 (EU) or 6n8 (USA), plastic
C2 - 470n plastic
C3 - 4n7 plastic
C4 - 330n plastic
C6 - 22n ceramic
C7, C8, C12 - 10n ceramic
C9 - 330p ceramic
C10 - 470p ceramic
C11 - 82p ceramic
C14 - 470u/25V electrolytic
C15, C16 - 220u/10V electrolytic

U1 - TLC272
U2 - 78L05
Q1 - BC557B
Q2 - BF245C
D1, D2 - Red!!! LED diode 5 mm, medium luminance (eg. 200 mcd)
J2 - jumper

Tips:
Following steps are recommended for the stereo version:

1. 1. If you have a possibility to measure static current gain of the transistor (h21e), find a pair of Q1's with similar h21e from about 5-10 pieces.
2. Place a temporary 3-pin IC socket piece instead of Q2's. Set the same input level value for both channels. Find a pair of Q2's from about 5-10 pieces which results in the same output level in both channels (you may follow the LED luminance if clipping is set). Then remove the sockets and solder the Q2's found.  

Transistor Q2 temporarily placed in socket.

Visit Pira.CZ Site


See more : Transistor FM Transmitter - Stereo Encoder - FM Transmitter Antenna

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C-Quam AM Stereo Decoder MC13028

This electronic circuit is AM stereo decoder that accepts the signal from the IF of a receiver (450 or 455 KHz) and decodes stereo medium wave broadcasts. It operates at 8-15VDC and provides standard level left and right audio output for direct connection to the audio amplifier.

It may be used to support 30Hz-15KHz audio but it depends on the bandwidth of the receiver's IF.

AM Stereo Decoder Circuit Schematic

Printed Circuit Board (PCB)

Layout PCB 

You may wanna reading: FM Transmitter

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5 MHz Bandwith Video Signal Amplifier

This video signal amplifier circuit is a broad band amplifier which will take the video signals from your VCR and will amplify them sufficiently to drive up to 3 monitors, TV sets (provided that they can accept direct video signals), or other VCR’s for recording from one video to up to three others. It will also make possible to record from one video to two others and at the same time have a monitor connected to check what you are recording. The amplifier is also very useful if the video recorder is far from the monitor.

Video Signal Amplifier schematic Circuit

Printed Circuit Board (PCB)

Parts List
R1,R14-R16 - 150
R18-R21 - 150
R2 - 10K
R3 - 1K5
R4,R8,R9 - 1K
R5 - 330
R6 - 3K3
R7 - 390K
R10,R13 - 2K2
R17 - 560
R11,R12 - 27
C1,C3 100u/16v
C2,C4,C6,C8,C10,C11 100n
C5,C7,C9 - 470u/16v
Q1-Q3 - BC548
Q2 - Bc558
Q4 - BC338
Q5 - BC558

You may wanna reading FM Transmitter

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50W Linear FM Amplifier with BLY90

This RF FM Amplifier is always essential for the amateur that wants it strengthens some small transmitter. The present circuit of BLY90 can give 50-60W power out with input control 15-20W in FM band II 88-108 MHz.

 FM amplifier schematic Circuit

Printed Circuit Board

FM Amplifier Parts List
C1-C4 = 10-80pF
C5 = 10nF
C6 = 1000pF
C7 = 100nF
C8 = 2200mF/35V
TR1 = BLY90
L1 = 1 Turn of diameter of 10mms, 1mm
L2 = 7 Turns of diameter of 10mms, 0,8mms
L3 = 3 Turns of diameter of 10mms, 1mm

Source: 50W FM Amplifier BLY90

Continue reading AV Modulator

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4 Watt PLL FM Transmitter

This transmitter circuit uses PLL method to generate stable frequency and the output power is selectable from 1 to 4 watts via an on-board jumper switch. It's designed using wide-band power amplifier technology, this eliminates the need to tune up the transmitter to "peak the power".

This PLL FM transmitter has an "Out Of Lock Power Down" circuit that will automatically reduce the output power to zero so that frequency adjacent radio stations will NOT be affected. A clean start up every time is assured without any disturbance to other channels.

The sound quality of the FM transmitter will match the most expensive exciters and walk over the rest! The response of audio frequency is absolutely level and linear to provide only the highest transmitter FM modulation quality. (PLL FM Transmitter Technical Manual)

Continue reading Audio Video Modulator

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4 Watt PLL FM Transmitter

Here's a Phase Locked Loop (PLL) FM transmitter circuit with high gain amplifier on the final stage. If the unit is to be used with a stereo encoder, the pre-emphasis must be disabled. The audio input network has a potentiometer to set the audio level and jumper selectable pre-emphasis.

The PLL FM transmitter uses the standard PLL architecture. The PLL error voltage is summed at the input of the audio buffer, which is implemented by a BC558 transistor. The PLL error voltage enables the RF output frequency to be locked to the frequency of a stable crystal reference oscillator. The summed PLL error voltage and audio modulation voltage is applied to the VCO by means of a dual varicap diode.







The voltage controlled oscillator (VCO) of the PLL FM Transmitter is based on a novel double-ended architecture operating at half the output frequency. The variable trimmer VC1 sets the centre frequency of the VCO - more of this later. An RF sample is taken from the VCO (still at f/2) to the PLL. The VCO receives its power from a separate zener-stabilised supply rail. The PLL programmable divide chain is implemented by a handful of 74LS logic (74ALS for the first divide), rather than using a synthesiser chip.



Download PLL FM Transmitter User Manual in pdf format : 1 2 3 4 5 6 7 8 9 10 11

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FM Stereo Encoder NJM2035

This stereo encoder is the perfect solution for those looking for a high quality stereo sound transmission at a low cost. This stereo encoder produces an excellent crystal clear stereo sound and very good channel separation that can match with many more expensive stereo encoders that are available on the market. It is all possible thanks to a 38KHz quartz crystal that controls the 19kHz pilot tone, so you will never have to calibrate or re-adjust the circuit.

NJM2035 offers superb quality and 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.


Source: NJM2035 Stereo Encoder

Continue reading Audio Video Modulator

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FM Stereo Encoder BA1404

This FM stereo encoder uses IC BA1404 for transmiting on FM band broadcast. Sub carrier frequency generated from 38 KHz Crystal. FM Power output is around 250mW. For input preamplifier used a couple of IC 741. You need a fm amplifier for boosting rf signal.

Stereo Encoder Schematic circuit


BA1404 datasheet

Another Stereo Encoder Circuit



You may wanna continue reading Audio Video Distribution Amplifier

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More 1934 Transmitter

I've gotten the components all mounted and the transmitter is ready for wiring. I learned a few things along the way...

30s vintage Sangamo mica capacitors are large enough that they don't mount well on their own leads. Each one must be mechanically supported, either by a solder strip or by screwing to the wooden sides of the chassis.

The wooden chassis takes 1 1/2 inches of available length and width. This can impact the layout. Using an all metal chassis there is space for a buffer stage between the oscillator and amplifier. With 1 1/2 taken off the length/width plus the added reinforcing across the middle it would be a challenge to fit the buffer stage in there.

Will the lead length be a problem? Certainly I wouldn't trust this spread out layout at 30MHz but it may be OK on 7MHz. Time will tell.

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Synthesised WideBand FM Transmitter

This project is a complete crystal-controlled Wide Band Frequency Modulated (WBFM) transmitter delivering a power output in the order of 10 milli-watts (+10dBm) using simple components. The transmitter is based upon the Phase-Locked Loop (PLL) principle, but due to the circuit's simplicity a true "phase lock" can never be achieved.

The transmitter has both 1v peak-to-peak 'LINE' input and 10mV 'MIC' audio inputs. These will accept audio input sources from external equipment, such as hi-fi, CD and computer equipment. The microphone input also has an in-built power source to energise an 'Electret' type condenser
microphone. The Radio Frequency (RF) output circuitry includes a three-pole filter for reduction of harmonics and other spurious signals. The spurious output signal level is better than -40dBc (0.0001 times the power of the wanted signal level), which makes the project suitable for driving an external power amplifier.The transmitter is powered from a 12v supply, but it will operate from 9 Volts to 16 Volts. The DC power input is equipped with a diode (D1), which protects the transmitter in the event the supply voltage is inadvertently connected the wrong way round.

Download Kit Intro Datasheet

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250mW FM Power Amplifier

This project is a simple 2-transistor VHF power amplifier, with about 16dB gain, and requires no tuning or alignment procedures. Wideband techniques have been used in the design and the circuit is equipped with a "lowpass" filter to ensure good output spectral purity. The project has been designed for assembly on a single-sided printed circuit board. The circuit is specifically designed to amplify the output of 7mW to 10mW WBFM transmitters (wide band) to a final level of 250mW to 300mW, after the filter.

Circuit Description
The first stage (Q1) operates in Class-A. Although Class-A is the least efficient mode, it does offer more RF gain than other clases of bias, and Q1 is a low-level stage, when compared to the higher power Q2 stage. The output of this stage is around 70mW of RF power. The stage is
untuned so that it gives a very broadband characteristic. The transistor is biased by means of R5, R6 and L6, and the residual (standing) DC current is set by R4. The input signal is coupled by C9 to the Base of the transistor. Q2 is operated in Class-AB which leads to greater efficiency, but the RF gain is only about 8dB, but it amplifies the output of Q1 to typically 250mW. Q2 is
biased by means of R3, R2 and L4. The input signal from Q1 is coupled to the Base of Q2 via C7.
The voltage regulator Q3 (78L08) is used to regulate the supply voltage to Q1 and the bias votages to both Q1 and Q2 so that the output RF power is relatively constant, even with large variations of supply voltage. Q3 also removes supply ripple as well as providing power for an
FM transmitter like Kit 3018 wireless microphone with the required DC 8v power.

The output of the amplifier is filtered with a low-pass filter to reduce the output spurious and harmonic content. The output filter consists of C3, C4, L1 and L2.

COMPONENTS
Resistors 5%, 1/4W, carbon:
10R R1 brown black black
22R R7 red red black
47R R3 yellow orange black
120R R4 brown red brown
470R R2 yellow violet brown
2K2 R5 red red red
4K7 R6 yellow violet red
2N2369 Q1
2N4427 Q2 1
Ceramic caps
33p C3
47p C4
1n C5 C6 C7 C8 C9
10n C1 C11
Ecaps:
220u/16V C2
10u/25V C10
78L08 Q3
RFC L4 L5 L6
Ferrite L3
3 turn coil L2
5 turn coil L1
2 pole terminal block
HS106 heatsink (download documentation)

Source:

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1W AM Transmitter

This AM transmitter circuit provides a nice, clean output of about 1 Watt (carrier power). Though designed for the medium wave band (circa 1.5 MHz) it would work equally well on higher frequencies (6.2 MHz for example) with a few tweaks in component values (see table on left - C15 should be adjusted for maximum output).

The carrier (produced by the 4049) is modulated at low-level by the MC1496 balanced modulator. There are then a couple of stages of linear amplification to reach the final output power so no modulation transformer is required. TR2, TR5 and TR6 are BC108 or similar; TR3 is a 2N3053 or 2N4427 or 2N3866 or any low/medium power NPN transistor. The main output transistors, TR4 and TR5 were originally 2SC1162 but BD135 or BD139 or other medium power RF transistors will do equally well. T1 uses a pre-tuned TOKO KANK3334 coil, the other transformers are wound on the red T50-2 toroids (the number of turns shown is the ratio, use about 4 to 5 times that number in reality - less at higher frequencies). The LED lights up if current in the output amplifier goes too high, so it's a kind of 'high SWR' warning.

Source: ZFM

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2.5 W FM Power Amplifier

This rf power amplifier design for a 2.5 Watt power amplifier for the FM band. An input of 50 mW gives a final output power of 2.5 Watts with a 13 Volt supply. The best bit is that the amplifier requires no tuning once it's built - it gives roughly the same gain and output power right across the FM band from 88 to 108 MHz.

There's even some hefty output low pass filtering to make sure that harmonic output is small and no interference is caused to users (mostly military!) on multiples of the FM frequency being amplified. A nice design based on, believe it or not, a military one...!
Source: ZFM

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88-108 MHz PLL FM Synthesizer

This fm synthesizer circuit is played with and optimised design for an 88-108 MHz synthesiser, programmable in 25 kHz steps. It produces about 50 mW output (and thus feeds nicely into the amplifier shown below) with no tuning required other than to set the inputs of the divide-by-N counter to the wanted frequency.

FM modulation is achieved just by injecting audio on the audio input (audio response is pretty flat from 10 Hz to over 200 kHz so can be used for stereo and RDS). This versatile design has also been used for link transmitters at around 48, 52 and 200 MHz with a few changes in the VCO and output filter, and by changing the reference crystal you can alter the channel spacing too. The power output is switched off until the synthesiser achieves lock to prevent transmissions on the wrong frequency (which can be disasterous if you've amplified it to high power and got it connected to a highly resonant antenna).



Source: ZFM

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Audio Processor for AM Transmitter

This audio circuit is used for AM transmitter audio procesing. It equipped with low pass filter circuit for AM spectrum. It's easy for use.

MK1 AM Audio Processor
My first attempt at an improved audio processor for GCR using a Plessey SL-6270 VOGAD (VOice controlled Gain Adjusting Device) which is designed more for PMR use than broadcast use but with the right parameters does a reasonable job. It deals with a massive dynamic range of inputs (about 60dB) which does tend to mean that if you don't set it up properly you can hear every tiny background noise in the studio. There's a bit of low and high-pass filtering on the input to avoid unwanted frequencies causing the compressor to 'pump'. There's also a lovely 7-pole Chebyshev low-pass filter on the output with a cut-off at about 6 kHz. All the op-amps are TL072 or TL074. Watch out for the difference between the 'earth' symbol and the 'ground' symbol as one relates to 0V and the other to mid-rail (typical supply voltage is 15V).

MK 2 AM Audio Processor
The Mark 2 version of the processor above. Now with an added limiter after the compressor (based around an MC3340 and a rather odd BSV71/BFR29 I.G.F.E.T.). A new 6-pole output low-pass filter to provide a tight fit to the transmitter specifications allowed at the time for closed-loop AM radio stations. There's a bit more HF boost (or pre-emphasis) before the clipper on this version to give the audio a more 'lively' feel. This design was in use at GCR for about 2 years until my super 3-band processor took over. Same precautions over the diagram as above apply and op-amps are also TL072 or TL072.


MK 3 AM Audio Processor (Part I)
The Mark 3 version got massively more sophisticated (and better sounding). This diagram is for the heart of the processor. It's a 3 band audio processor/limiter/compressor (call it what you will) with a few special features: (1) The decay on the bass compressor is tied in to the mid compressor which gives a much more balanced sound, and (2) there are cross-overs before and after each compressor, thereby reducing any distortion produced. The resulting sound is very loud and very impressive. The 3 audio bands compressed are 0-250 Hz, 250-1300 Hz and 1300-6500 Hz. The +/- 8V supply is quite critical as it sets the threshold for compression to the MC3340 chips. There's still a transmitter kicking around with this processor in it - if I can get my hands on it I'll record some output.


MK 3 AM Audio Processor (Part II)
This is the second half of the Mark 3 diagram and shows the input high and low-pass filtering; the clipper (with a snazzy LED to show when clipping is occuring); and a new and even better output 6.5 kHz low-pass filter together with a phase corrector to provide overshoot compensation (and therefore allow the transmitter to be driven harder).




AM Low Pass Filter Response
The frequency response of the output filter is flat to 6 kHz, -3dB @ 6.5 kHz, -23dB @ 7.6 kHz and -40dB @ 9 kHz, which fits exactly the allowed response for closed-loop AM stations for which it was designed. Without the overshoot compensator, the filter has an overshoot of around 2.6 dB; with it, overshoot is virtually nothing - thereby giving a 2.6 dB increase in loudness. All components (including the capacitors) need to be 1% tolerance for this circuit to work properly.

Source: ZFM

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FM Stereo Encoder

This Stereo encoder circuit built with MC1496. It produces a very clean signal with good separation (it performed as well as any other encoder, which included some expensive professional ones) and has been used on many professional commercial radio stations. There's no input filtering on it so it has to be proceeded by a 15 kHz low-pass filter (which was something I put on my processor instead of on the encoder). It needs a +/- 8 Volt supply but +/- 9V would work equally well and it produces 1 Volt peak-to-peak into a 75 Ohm load (and a bit more into a high impedance one) with 0dBu audio drive. XL1 should be a 4.864 MHz one.

The wires and extra PCB (off the top of the shot) in the picture are for a composite clipper that was added afterwards, which provides about another dB and a half of loudness.

Source: ZFM

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QRP from Frontenac State Park

Sunday afternoon, July 5, I got over to Frontenac State Park for some picnic table QRP. The picnic area there sits at the edge of a 400' bluff over looking the Mississippi River. Below the park is Lake Pepin , a naturally wide part of the upper Mississippi. To the east, across the Mississippi/Lake Pepin, is Wisconsin. The weather Sunday was sunny but not too warm in the shade, perfect for picnic table QRP.

Using my K1 running 4 watts and feeding a 67' end fed wire I worked K4BAI(Columbus, GA), WA3PAK(Marion, OH) and N7JOX(northern CO near Cheyenne, WY). All in all a satisfying and relaxing afternoon....

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My version of the BakerTweet

In case you haven't heard about the awesomeness, the BakerTweet (www.bakertweet.com) is an Arduino based twitter client. It's a little box that sits on the wall of a bakery, and whenever something tasty comes out of the oven, the baker can select the product and let the world know via Twitter that there's a fresh batch of croissants ready.

I thought this was a great idea! And I've been wanting an excuse to hook my Arduino up to twitter for ages.

What you'll need:

• Arduino board (I'm using the Duemilanove)
• Ethernet shield
• LCD shield
• 3 push buttons (if your LCD shield doesn't come with them)

How to do it:
All the elements of this project are already widely available. People have been using the official Arduino Ethernet shield to sent Twitter updates for ages. My problem was that I bought the much cheaper, ENC28J60 based Ethernet shield by nuelectrnoics. It wasn't until tuxgraphics.org brought out their new TCP/IP stack, and Andy modded it for the Arduino that I was able to send Twitter updates from it.

The LCD shield also proved a bit of a hassle. Mine is also from nuelectronics and wouldn't sit properly on top of the Ethernet shield. The RJ45 socket from the lower shield is a lot higher than the pin headers, and there were some through-hole pins from the buttons poking through making it impossible for the two boards to mate.

I soon solved that though by desoldering most of the buttons, shortening the leads, and re-soldering them in a surface mount fashion. They work just fine, and the two boards will now mate (not perfectly, but enough to make a solid connection).

Code:
The code for my Arduino sketch is located here. Basically, you just plug the board into an Internet router (over a wired LAN), power the Arduino somehow, and then use the buttons to scroll through the possible tweets. Once you've found the one you like, click the send button and it'll post the tweet to your Twitter account.

What's Next?
I'd love to make this thing wireless, using a WiFi card. I bet they aren't cheap though....

read more "My version of the BakerTweet"

Cheap Joystick and Accelerometer for Arduino from Wii Nunchuck

For ages now I've been wanting to play with an accelerometer but didn't really fancy paying £20-25 for the privilege. I'd also seen a lot of posts about people using the joystick from a Wii Nunchuck to control robots, servos, cameras, etc, which I didn't have a lot of interest in. Then I remembered that the Nunchuck controller actually has an accelerometer built in. Long story short, I'm now short one Nunchuck and plus one accelerometer.

The economics of this one really work out, since a Nunchuck is usually only about £15, and communicates over I2C which saves on IO. So far, the lowest price accelerometer I've found was over £20 and communicated using 3x analogue signals.

Obviously I'm not the first to make this realisation. A quick Google search took me to http://www.windmeadow.com/node/42, which gives a great tutorial on how to wire it up and gives a sample sketch to get you up and running.

I wanted a way to visualize the data coming out, just so I could see how it looks when I make a few gestures or use the buttons and joystick. I'm not the greatest fan of Processing (mainly because I haven't used it an awful lot) but I am a big fan of Java. I created a program which shows me the current levels of each of the 5 axes (x, y, z, joystick x, joystick y), and the 2 buttons. It also graphs the xyz-axes over time. Cool eh?


As with most of my programs it needs a lot of attached Jar files, so here's my Eclipse workspace folder in zip format.
Note: you'll need to tweak the Windymedow sample sketch a little to work for my Java program - specifically you'll need to change the value separator in the "print()" function to a comma, not a tab.

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Stereo FM Transmitter BH1415F

This Electronic circuit is a stereo FM Transmitter based on BH1415F wireless audio link IC. Phase Locked Loop (PLL) controller use PIC16F628 and the the PLL frequency programming can be displayed with 8x2 and 16x2 LCD. Frequency Range 88-108 MHz

BH1415F can be supplied with 6 - 15V voltage, consumes only around 25mA while providing very sound quality and improved 40dB channel separation. BH1415 is only available in SOP22 IC case and this may be an inconvenience for some folks. On the other hand, because the chip is smaller than regular DIP-based ICs it is possible to fit the entire stereo coder on a small PCB.




Download Documentation BH1415F

BH1415F Datasheet

Source

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