The main projects presented
1. Time base
The time base presented generates 5 signals that have a very common practical utility: 200Hz, 100Hz, 50Hz, 10Hz and 1Hz. All signals are rectangular in shape and have a peak-to-peak aptitude close to the supply voltage.
2. 2x40W stereo audio amplifier
There is a power stereo audio applicator made with integrated circuit TDA8560Q, specially designed by Philips for use in car cassette players and power amplifiers.
3. Frequency meter 0.1Hz - 1.5GHz
Universal frequency meter FC-7150U, produced by LG Precision company is controlled by a microprocessor and allows the analysis of signals of a very high dynamics, the display is made on a 9-digit display.
4. 250W audio amplifier
It has a 250W audio amplifier based on two integrated circuits TDA 7294.
5. Strobe
The article presents a stroboscope with direct supply at 220V, which is based on the MOS integrated circuit CD4093.
6. HB9CV antenna
The realization of a new type of antenna with special electrical parameters cannot be the option of chance, but the result of a long experience based on deep practical knowledge and theoretical studies.
HB9CV is the amateur radio call sign, obtained in 1937 by Rudolf Arthur Baumgartner, born in Bern on October 11, 1914. His experiments as an amateur radio had multiple applications in civilian and military terms.
7. TV service
The article presents in detail the debugging of the floors equipped with TDA3561A and TDA3592A.
8. MC 3359
Integrated circuit MC3359 is specially designed by Motorola as a midrange frequency amplifier with narrowband frequency modulation.
This circuit includes the functions of oscillator, mixer, aptitude limiter, automatic frequency control, discriminator, squelch, mute and scan control.
9. Universal oscillator
An oscillator is described that works with any oscillating circuit having a frequency within the limits of 20Hz… 200MHz.
10. Level indicator
There is a level indicator based on the integrated circuit LM3914.
11. Electronic thermometer
The article presents a precision electronic thermometer that works in the range 0… 100C, based on the integrated circuit ICL7107.