Dilshan R Jayakody’s Web Log

Due to the advancement of audio technologies reel to reel audio tapes are now classified as a rare item. The biggest problem with the reel to reel tapes is a fungus . The fungus is developed on old unused tapes due to humidity exposure. Also, another problem with old tapes is that the lubrication on the surface of the tape starts to deteriorate and tape starts to stick to itself, and this leads tape to break during the playback. Most of them that have Fungus can be fixed by using a tape cleaner. But these days reel to reel tape cleaners are not available to buy and because of that, we decided to build simple tape cleaner by using parts of old reel to reel tape players. The core component of this player is an induction motor which we got from an old reel to reel player. The motor which we used in this project is the Sony HC-134. HC-134 is 100V single-phase, capacitor run, induction motor with 1500 - 1800 RPM. Recommended auxiliary winding capacitor for this motor is 1.5μF. To delive

HiFi Studio 1 is portable boombox manufactured by Telefunken in around 1979. This player consists of 4 band radio (with LW, MW, SW, and FM), cassette player/recorder and with 2 × 30W audio power amplifier. Restored HiFi Studio 1 This unit is designed using both ICs and transistors. The receiver of this unit is built around TDA1047, TBA570 and BA1320 ICs. Tape player/recorder is mainly build using NPN transistors and special Telefunken IC and 4066 ICs are used to get Telefunken's proprietary HIGH COM tape noise reduction feature. The power amplifier of this boombox is transistor based and it uses a pair of TIP130 and TIP135 transistors in its final stage.

TC-252 is 3-speed reel to reel player manufactured by Sony in around 1970 – 1972. This is transistor based tape player with 4W × 2 audio output power, sound-on-sound, and sound-with-sound recording features. The TC-252 which we got to restore had many problems. The major problem is someone alters the circuit in that recorder and attach LA4440 power amplifier into the circuit. Apart from that, the motor speed of that recorder also starts to decrease after 10min of continues playback. Other than above two major problems it had some mechanical problems in playback position and all the potentiometers in the front panel are damaged beyond repair. TC-252 main PCB after restoration. As a first step of the restoration, we remove the LA4440 module attached into that recorder and rewire the player with original wiring layouts. After rewiring we check all the transistors in that player and find out that the couple of 2SC634 transistors are damaged in that player. Because 2SC634 is not a