Home-brewed Theremins ... and other strange devices

Canon EX1Hi HI8 Camcorder Restoration / Repair Project

At a local flee-market on 12.09.2020, I found a vintage Canon EX1Hi HI8 Camcorder with accompanying accessories. The unit was non-operational due to leaking SMD electrolytic capacitors as expected. It was introduced by Canon in 1991 and was high-end equipment at that time, applying interchangeable lenses.

A cassette stuck inside the drive-mechanism which could only be removed by completely disassembling the camera and applying external supply voltage to the ejection drive-mechanism motor.

The unit uses several PCBs equipped with hundreds of those (possibly) leaking SMD electrolytic capacitors. I decided to exchange every single of these capacitors to return the Canon EX1Hi HI8 Camcorder to working condition.

At the moment (14.09.2020), this work is in progress; capacitors have been ordered.

It is likely that the unit holds additional problems which will show up as soon as it can be switched on without shutting down after some ten seconds.

In the current condition, the EX1Hi can be switched on, the display shows low-bat warning, the view finder monitor displays a vertical (!) line, the auto-focus works to move the lens and the unit switches of after a few seconds (due to low-bat). The camera was operated using a laboratory power-supply for current measurement and to prevent additional failure due to possible over-current. The pictures show the complex electronics inside the Canon EX1Hi HI8 housing and the extensive wiring.

Some of the PCBs are real SMD electrolytic capacitor graveyards.

Canon EX1 accessories

The following pictures show the accessories which came with the EX1 camera: remote control WL-100, zoom lens CL 8.7-69.6mm 1:1.4-1.8, zoom lens CL 8-120mm 1:1.4-1.2, extender CL 2X, power-adapter CA-100E, power-adapter cable DC-100, accumulators BP-E718 /  BP-E722 and stereo/zoom microphone. The accumulators are of course defective. The power supply unit works.

Canon EX1 disassembly

The following pictures document the process of disassembling the EX1 camera.

Canon EX1 printed circuit boards (PCBs)

The following pictures show the printed circuit boards (PCBs) and the messy cabling of the disassembled EX1 camera. The PCB indication numbers are as follows:  


D943 AFM.2 / DH1-0826-02 / DG1-1198

DL41 PAL SS / DG1-1410 / DH1-0959-01

DH1-0835-02 / D943S PAL VC / DG1-1210 / KS112

DG1-1383 / DH1-0954