Latest BH1415 Stereo Encoder design from RHOM that includes a lot of great features in one small package. It comes with pre-emphasis, limiter so that the music can be transmitted at the same audio level, low pass filter that blocks any audio signals above 15KHz to prevent any RF interference and crystal based stereo encoder for stereo transmission.

BH1417 Stereo Encoder design from RHOM that includes a lot of great features in one small package. It comes with pre-emphasis, limiter so that the music can be transmitted at the same audio level, low pass filter that blocks any audio signals above 15KHz to prevent any RF interference and crystal based stereo encoder for stereo transmission.

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.

This map, armored also enables automatic MONO / MPX through a low-pass filter, even with a multiplex on its entry by using an ON / ON, panning, the whole spectrum MPX more RDS is sent to the synthesizer, on the other hand when it is in a position MONO, the low-pass filter is activated and share its cutoff frequency at 15 KHz, only modulation G + D is sent to the synthesizer, as 19 KHz. 19 KHz carrier, the signal multiplex and subcarrier 57 KHz is thereby eliminated, which provides ease of use for example in a string of issue relay tuner, if the link between the issuer Departure and receiver re-issue was not of good quality stereo, you sufficient to switch to mono to improve sound quality, you can then connect the RDS encoder at the re-issuer.

BA1404 based stereo encoder.

This stereo encoder is a halfway between analogue and digital processing. It combines the best from both domains to provide high-quality and easy to build device. The sampling frequency used in this stereo encoder is 97 times higher than the pilot tone frequency. This makes very easy to reject all spectral residues around the sampling frequency without affecting the main signal characteristics. Using of a microcontroller allows to build this stereo encoder with reduced part count and get excellent results in real operation. This stereo encoder advisedly does not contain any preemphasis circuit. Remember the key fact: a compressor/limiter/clipper device must be always present between the preemphasis circuit and the stereo encoder or modulator. Only this configuration ensures loud sound without exceeding the maximum frequency deviation limit (75 kHz). The stereo encoder is designed to provide really good sound. This always needs to use the compressor/limiter/clipper device where the preemphasis is precisely assured.

Converts your mono FM Receiver to stereo.

Phase-Locked Loop FM Stereo Demodulator.

Stereo demodulator based on LM1800 IC.

The NTE789, a monolithic silicon integrated circuit, is a stereo multiplex decoder intended for FM multiplex systems. This stereo multiplex decoder requires only one low–inductance tuning coil (requires only one adjustment for complete alignment), provides automatic stereo switching, energizes a stereo indicator lamp, and operates from a wide range of voltage supplies.

Uses high quality NJM2035 stereo coder IC.

With BA1404 and 15 KHz low pass filters.

Stereo Broadcast Limiter Circuit for Ramsey.

Stereo Decoder with TDA1591 IC.

As you probably know, to enable stereophonic broadcasting, audio channels LEFT and RIGHT have to be specificaly encoded in such a way that FM receivers can reconstruct stereo. This is a low cost, but powerful, stereo coder. Since the schematic is very 'clean' there's no full documentation available. Just note that : * Trimmers adjust 19KHz pilot tone and output levels (see schematics). * Cap. trimmer fine tune the 19KHz pilot tone frequency (from 76KHz crystal).