My cousin was not very interested in radio so I acquired it a few years later in my teens.
Recently I decided to refurbish it and this is the result.
Cosmetically it was always in pretty good shape. In the past the radio worked quite well but I could not get the BFO to function. After spending some hours finding the correct diagrams for this European version, I proceeded to correct a few problems it had developed over time. All the switches and controls needed a good clean. I cleaned and reassembled the slide switches on the front panel and sprayed the Rotary Band Switch, RF gain, Volume and BFO pots with cleaner to get them working properly. I re-aligned the IF Stages and found the AGC feedback capacitor was open circuit. I then set to work on the BFO stage. The BFO was oscillating around 600kHz which was way off the 455kHz IF stage, adjusting the coil core would not bring it below 600kHz. I decided to pad the ocillator circuit with some capacitance and after some experimentation found a value that brought it down to around the 455khz area I had also fitted a trimmer capacitor for good measure and with the core adjustment and trimmer brought its frequency to 455kHz with the BFO control set in the middle of its range. I went through the tune up procedure in the instructions and everything now works great. The original 2 internal 6v Dry Cell type Batteries are no long available so I replaced them with a small sealed lead acid rechargable battery that charges from the external power cable as shown below. Notice the co-axial antenna socket mounted on the rear of the radio is the same style as is used on televisions in the UK.
Diagrams for the Mochican GC-1U - Part 1 - Part 2
