Feedback welcome...


The most serious omission IMHO is there is no reference to
the hazards encountered when servicing, or connecting peripheral
devices or test equipment to "live chassis" radio and televisions.
These was mainly valve or hybrid (valve & semiconductor)
sets, but some "all transistor" sets were also live chassis.

The chassis is supposed to be connected to the supply neutral, but
even if you check the polarity it would be very unwise to work
on it without an isolating transformer.

After about the mid 70's a different kind of live chassis is
encountered. This time the chassis is connected to the -ve
of the mains bridge rectifier. Consequently, the chassis is
*always* at half mains potential irrespective of plug polarity

With both these variants of live chassis, use an isolating transformer
rated for the full continuous load (not an insubstantial piece of kit)
whilst the back is off, and ideally, when in normal operation too.

Finally, the aerial socket will be isolated with built-in capacitors,
ensure this hasn't been tampered with. Imagine getting a serious shock
whilst in the roof!



--
Graham.

%Profound_observation%