Dilshan R Jayakody’s Web Log

TC-500 is 4 track stereo reel to reel player which is built around 1960 - 1970 by Sony Corporation. This is vacuum tube base reel to reel player with 2 × 3W audio output power. TC-500 is dual speed (3¾ and 7½ ips) tape recorder and it support reels up to 7 inches (18cm). Amplifier stage of this tape recorder is built around 12AX7, 6AU6 and 6AQ5 vacuum tubes and the 12BH7 tube is used in biasing oscillator. Other than above tubes, 6CA4 is used in PSU for rectification. Restored Sony TC-500 reel to reel tape recorder. Recently we got a chance to restore TC-500 reel to reel player which we got from our friend. The player which we got is heavily damaged and we spend nearly 2½ months to restore this player. In the first stage of restoration, we disassemble mechanical parts of this player and clean everything. In this player capstan idler wheel and take-up, idler wheel is damaged beyond repair and we reconstruct those wheels using rubber sheets.

Few months back I got an old Heathkit IO-12 Oscilloscope from my friend and at the time of delivery this unit is not under the working conditions. Heathkit IO-12 is Value based laboratory oscilloscope with following technical features, Frequency Response : 3 Hz to 4 MHz ≅ 5 MHz Sensitivity : 0.025V/inch Rise time: 8µS Sweep Range : 10 Hz to 500 kHz When I remove the casing of the oscilloscope I found several damaged components (specially capacitors) and wires. After making the careful observation and testings I decided to rewire the whole oscilloscope with new components except the following, 12BH7 Dual Triode 12AU7 Dual Triode 6AN8 Triode Pentode 6AB4 Triode 1V2 ½ Wave Rectifier 6X4 Full Wave Rectifier 6J6 Dual Triode Main Transformer Front end controls (including switches, potentiometers, connectors and indicator) Most of the inductors Cathode Ray Tube, etc As mentioned in the above list all the Values, transformers and some of the critical components are in good condition. Only t...