The Optacord 403 is a 2-track device from Loewe Opta. It was built in the early 1960s. It features two tape speeds (4.75 and 9.5 cm/s), a magical band as a volume control and is equipped with tubes (EF86, ECC83, EL84, EC92, EM84). When I got it, it was still functional, however, the recordings were very quiet and distorted. Also a thorough cleaning of the audio heads brought almost no improvement. This I could only notice, after exchanging some capacitors in the amplifier part, especially the WIMA capacitors.

The chassis has been removed from the housing. This makes all parts of the device easily accessible. You can see the power supply on the left as well as the external rotor motor, which is pivotally mounted. At the bottom of the picture you can see the preamplifier board and on the right the power amplifier with an EL84.

The view from the front. One can well recognize the flying wiring.

The power supply with the big power transformer on the right side.

The device on a first test run. The playback was clear, but very quiet. A recording made with this unit was even quieter, and it sounded very distorted. Several capacitors in the preamplifier section were responsible for this, which had very low resistance values. After exchange them, recordings and playbacks were loud and clear. The mechanics are relatively simple and can be fully functional even after this many years.

Here the winding plates were removed; They can simply be pulled off.

The bearing for the flywheel. This is only stored on the underside double. The part with the blue cable is the erase head, which simultaneously serves as a left tape guide.

After all bearings were re-lubricated and everything has been reassembled, the heads and the band guides were adjusted.

The casing with the speaker. It has a surprisingly good sound for its small size. This is probably be due to the final stage with an EL84.