Another one...
The surplus TEA5711 AM/FM stereo receiver and TDA7050 stereo amplifier integrated circuits in my junk box were begging to be used, and since those ICs were out of production and difficult to obtain, I decided to make a second stereo FM receiver, which you see here.

Slightly different...
This receiver differs slightly from the first one. It is smaller in size, it is housed in a homemade case, it has no balance control, the vernier mechanism is part of the tuning capacitor shaft, and it runs on 3 volts supplied by 2 AA batteries.

Similar performance...
The performance of this receiver is similar to that of its big brother. High sensitivity allows reception of distant stations from across the Mediterranean (Cyprus). Good selectivity is obtained with narrow bandwidth ceramic filters. AFC (automatic frequency control) locks on stations well for drift-free reception. Stereo separation (effect) which depends on signal strength is very apparent on strong signals. And with high quality headphones, the sound is rich with deep base and high treble, for hours of enjoyable stereo music!

With the Sony ICF-SW7600G...
I compared this receiver with the Sony ICF-SW7600G. Needless to say, I used the same headphones (Koss Pro35A), the same station and the same broadcasted material. The stereo separation on my receiver (30 dB according to the TEA5711 spec. sheet) was better then on the Sony, but the mid-range frequencies (around 8 KHz) were stronger on the Sony. This led me to conclude that even the big companies will cut corners to reduce price and increase sales!

The receiver is housed in a 6 x 4.5 x 2 inch box I made from pieces of single-sided PC boards. Controls from left: on/off, volume, stereo/mono and tuning. A 7 to 1 vernier embedded in the tuning capacitor coaxial shaft offers smooth tuning. Stereo reception is indicated by the red LED. The stereo/mono switch allows clearer reception of weak stereo stations. High quality stereo headphones with 32 or 60 ohms impedance can be used to listen to the receiver. A removable telescopic antenna can be swiveled, extended and collapsed for best reception.

The circuit was built "Manhattan style" on a 2 13/16 x 3 15/16 inch piece of single-sided PC board. An SDIP socket was used with the TEA5711 to allow easy connection of the components. Slug-tuned coils (red squares) were adjusted and sealed with wax for stability. Ceramic filters and resonator are on the right side of the TEA5711 IC. Black trimmer pot (lower left) is adjusted once for best stereo separation. Stereo amplifier TDA7050 sits in a DIP socket (lower right). Dual-ganged volume control is at lower center. Dual-ganged variable capacitor with coaxial vernier shaft is at left. 4 pieces of PC boards with center nuts at the corners are used to hold a cover. Battery holder at top right holds 2 AA batteries which supply 3 volts to the receiver.

Close-up view of the board. A printed circuit was not necessary to assemble the high frequency circuitry. The copper plane served as a common ground and improved stability. Bending the pins of the TEA5711 SDIP socket was a frustrating experience as they were fragile and prone to breaking; the missing pin on the left actually broke, but luckily it was not a required pin!

A piece of single-sided PC board attaches to the 4 supports at the corners with machine screws (see above) and serves as a cover for the receiver. 3 rubber feet on the cover allow the receiver to be used on any surface.

Not much at the back. Just my signature and the date of production of this high performance receiver.

The receiver circuit is a slightly modified version of the application circuit for the TEA5711 AM/FM stereo receiver IC.