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letzte hinzugefügte Downloads
 2x125W Tiefton Doppel Endstufe | | Beschreibung: | 2x125W Tiefton-Doppel-Endstufe jeweils mit eigenem Regelnetzteil (mit rückläufiger Strombegrenzung) für Aktivbox mit 2 Basschassis-Gruppen 2xCompoundsystem mit geringen Klirrverzerrungen | | | Dateigrösse: | 300 Bytes | | Hinzugefügt am: | 27-Jan-2010 | | Downloads: | 194 | | Kategorie: | Elektronik UpDownloads 2 | | Homepage | Eintrag bewerten | Details |
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 Unusual Frequency Dividers | | Beschreibung: | The following circuit uses a 75140 line receiver to form an injection locked oscillator. The circuit is similar to the common op-amp square-wave oscillator with values selected
to keep the voltages within the recommended operating ranges. The frequency to be divided is coupled through a 5k resistor to the positive feedback input of the comparator
superimposing a 0.5 volt squarewave. The small squarewave toggles the comparator when the sawtooth voltage on the capacitor comes close to the DC level on the positive
feedback input. The result is that the comparator output frequency is an integer submultiple
of the input frequency. Since the comparators exhibit good temperature stability
and precision, the division ratio can be quite high. A division factor over 20 is practical
and since the 75140 is a dual line receiver, two dividers may be cascaded for division
ratios over 400. For ratios higher than 4, increase the 5k series resistor to 10k. | | | Dateigrösse: | 300 Bytes | | Hinzugefügt am: | 22-Jan-2010 | | Downloads: | 88 | | Kategorie: | Electronic UpDownloads in English | | Eintrag bewerten | Details |
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 Interfacing a Graphic LCD with a Z8 Encore | | Beschreibung: | Interfacing a Graphic LCD with a Z8 Encore! 64K Series Flash MCU - Z8 Encore! XP Flash Microcontrollers
Zilog’s Z8 Encore! XP® products are based on
new Zilog’s eZ8 CPU and introduce Flash memory
to Zilog’s extensive line of 8-bit microcontrollers.
Flash memory in-circuit programming
capability allows faster development time and program
changes in the field. The high-performance
register-to-register based architecture of the eZ8
core maintains backward compatibility with
Zilog’s popular Z8® MCU. Z8 Encore! XP MCUs
combine a 20 MHz core with Flash memory,
linear-register SRAM, and an extensive array of
on-chip peripherals. These peripherals make the
Z8 Encore! XP MCU suitable for various applications
including motor control, security systems,
home appliances, personal electronic devices, and
sensors. | | | Dateigrösse: | 300 Bytes | | Hinzugefügt am: | 20-Jan-2010 | | Downloads: | 124 | | Kategorie: | Electronic UpDownloads in English | | Eintrag bewerten | Details |
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| Remote Synthesised VFO | | Beschreibung: | A Remote Synthesised VFO for the HW9 by Stewart Rolfe / GWØETF
This project provided an opportunity to put to good use a long held interest in Programmable Interface Controllers (PICs) and an urge to play with the new Direct Digital Synthesiser chips which had just started appearing in the amateur radio press in such articles as G3XJP’s excellent Pic’n Mix in RadCom1. The
following describes an exercise in self education first and foremost, but one which has been applied in practice to cure some basic problems in an otherwise fine QRP transceiver. Though aimed at one specific radio it is hoped that the description will be of more general interest and could be easily adapted to other
situations. Most of the technical content is a compilation of previously published ideas and articles with a
small amount of original material mainly connected with the need to adapt to the specific case of the HW9.
All material used is fully acknowledged, and reference to the original sources will provide a fuller description
of what is included here. | | | Dateigrösse: | 300 Bytes | | Hinzugefügt am: | 09-Jan-2010 | | Downloads: | 123 | | Kategorie: | Electronic UpDownloads in English | | Eintrag bewerten | Details |
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| DIGITAL VFO | | Beschreibung: | The DDS digital VFO gives you the full control of your receiver and transmitter, with performance like modern commercial transceivers. The IF frequency value can be programmed (i.e. 5.645 KHz for Drake, 4915 KHz for Elecraft K1 or K2, xx MHz for many other commercial or homebrew transceivers) You
can set it for zero beat in your receiver, for exact calibration if the carrier oscillator of your receiver is not correct.
It is possible to set-up different IF offsets for RX and TX, as it maybe the case some homebrew transceivers, where the TX IF is different from the RX IF. The specific set-up is reported in the following description. To change the IF RX frequency value, simply tune the frequency required, i.e. 5645.125,
and press keys SPL and RIT for 2 seconds, at the same time.
Now the new IF value for the RX is stored in memory. (the VFO output frequency has a positive offset frequency equal to “ Frequency displayed + IF” ) To change the IF TX frequency value, simply tune the frequency required, i.e. 5.645.125,
and press keys VFO and SPL for 2 seconds, at the same time.
The new IF value for the TX is stored in memory. (the VFO output frequency has a positive offset frequency equal to “ Frequency displayed + IF”) To have the TX functionality is necessary to put a GND to PIC I/O pin 15 ( PORT C4). You can use the PTT mike line of your transceiver for this control. | | | Dateigrösse: | 600 Bytes | | Hinzugefügt am: | 09-Jan-2010 | | Downloads: | 133 | | Kategorie: | Electronic UpDownloads in English | | Eintrag bewerten | Details |
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| Direct Digital VFO | | Beschreibung: | An Advanced Direct-Digital VFO
The author used an Analog Devices AD9951 DDS IC in a new VFO design.
This article describes a hardware design that features the Analog Devices AD9951. A 14-bit D/A converter at the output, and
a much higher rated clock speed than the 98xx family allows a frequency-dependent SFDR in excess of 70 dB, and approaching
80 dB with a 400 MHz internal clock frequency. It puts the latest technology on a four layer, 3 inch circuit board, and can be used as
a stand-alone VFO or as part of a multi-loop frequency synthesizer. There are two stages of RF filtering included in the design: the first
between the 9951 DDS and the output buffer amplifier, and the second after the buffer, at the board output. A significant capability
for software expansion exists, as only about 2 KB of program memory (out of an available 12 KB) is presently used. As in previous
designs, tuning is accomplished with a shaft encoder. An inexpensive LCD provides a frequency readout. | | | Dateigrösse: | 300 Bytes | | Hinzugefügt am: | 09-Jan-2010 | | Downloads: | 140 | | Kategorie: | Electronic UpDownloads in English | | Eintrag bewerten | Details |
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| PIC Programmer and Test-Demonstration Board | | Beschreibung: | 1 Introduction
2 Hardware Description.
2.1 PIC programmer
2.2 Project/Demonstration
2.2.1 PIC system clock (crystal).
2.2.2 LEDs
2.2.3 Pushbuttons
2.2.4 LCD.
2.2.5 Rotary Encoder
2.2.6 Speaker .
2.2.7 Signal generation with the NJQRP DDS Daughtercard
2.2.8 Signal Conditioner
2.2.9 CW paddle Input via a Stereo Jack
2.2.10 Transmitter Keying via a Stereo Jack.
2.2.11 Frequency Counter
2.2.12 How to Drive a Relay from a PIC
3 PIC-EL Assembly
3.1 Parts Identification
3.2 Test Points
3.3 Assembly
3.4 Final installation and Basic PIC-EL Test
4 PIC-EL Computer Interface
4.1.1 Installing FPP
4.1.2 Installing FPPA
4.1.3 Using FPP / FPPA
5 PIC-EL Diagnostic Program
5.1 Test LEDs
5.2 Test Pushbuttons
5.3 Test Speaker
5.4 Test Encoder
5.5 Test Paddles
5.6 Test Transmitter Keying
5.7 Test DDS-30
5.8 Test DDS-60
6 Elmer-160 Lessons | | | Dateigrösse: | 900 Bytes | | Hinzugefügt am: | 09-Jan-2010 | | Downloads: | 114 | | Kategorie: | Electronic UpDownloads in English | | Eintrag bewerten | Details |
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| Microcontroller development board | | Beschreibung: | 1 General information
2 Features
3 Block schematic
4 General description
5 Programming software
6 Testing the development board
7 Supported PICmicro microcontrollers
8 Pin out details and bus connections
9 Liquid crystal display
10 On-board analogue sensors
11 External analogue sensors
12 Circuits
13 External digital sensors | | | Dateigrösse: | 300 Bytes | | Hinzugefügt am: | 09-Jan-2010 | | Downloads: | 90 | | Kategorie: | Electronic UpDownloads in English | | Eintrag bewerten | Details |
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