C-6204
Operation of the electronic circuit
This radio has SC1088 or TDA7088T integrated circuit, which is used by manufacturers of portable radios.
This integrated circuit contains all the basic components required for the construction of a radio. Includes a frequency locked loop
(PLL), intermediate frequency (IF) centered at 70 kHz, modulator block, etc.
Working with as low as 1.8 V voltage integrated circuit that requires very little current (4.2 mA), so it is an ideal solution for portable
applications.
The integrated circuit ASIC also includes an automatic squelch circuit (MUTE) on pin 1 to suppress weak signals. However, this is
an optional feature that allows the technician experiment with receiving signals weaker radio.
It is ideal for an integrated radio enthusiasts due to its low cost and very few external components circuit. The variable capacitors
to tune the stations are currently expensive, however this chip provides the option of using a single diode VARICAP (type 910) for
tuning.
The system works station search in one direction, from the lower band limit to the upper limit.
Block diagram of the integrated circuit
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