motogb: 828; (Serbvicing & repair)

The pictures I have uploaded were taken by me during the repair of a Motorola 828.  All three AF117 transistors, which are known to suffer internal faults commonly referred to as the 'tin whisker' problem, resulting in leaks or short-circuits between, e.g., the collector and screen, have been replaced with more modern equivalents.  I have also replaced the by now 50 year old electrolytic capacitors with modern types, using the nearest available capacitance values and working voltages wherever possible, althout the  main smoothing capacitor C109, originally 1000uf, has been replaced with a 2200uf, and C10 (200uf) with a 470uf.   Hopefully the pictures I've contributed, plus these notes, will be helpful to others servicing or restoring this series of radios.  The replacement transistors I used are Russian devices similar to AF127s, but with pin-outs identical to those of the AF139, which causes sompe problems when fitting them in place of AF117s, which I overcame in two cases, by mounting them 'upside down' and extending one or more of the leads.

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