Gary S. Crutchley
Ever Ready Sky Master 14/10/2014
One of the more recent additions to my vintage radio collection, an Ever Ready Sky Master dating from approximately 1962. It was in very good condition when I purchased it, although it did need a good clean, and one of the control knobs needed to be repaired. The usual modifications were also necessary in order to accommodate modern batteries.
This set was released after the Ever Ready Sky Leader which I also have in my collection, and is slightly smaller:
The Sky Master continues to work well, and is in daily use, however, it does suffer from a peculiar and interesting issue known as "tin whiskers".
This set contains Mullard's AF series transistors, the construction of which consisted of the junction mounted inside a metallic case, insulated with a silicone grease. Over time very fine tin dendrites grow between the junction and the casing, eventually causing an internal short circuit and loss of operation. The only cure is to replace the transistors, but tapping them with a screw driver breaks the dendrites but they do grow again.
The tin whisker problem had some very serious ramifications, and was studied extensively by NASA as the issue affected the operation of their space craft causing major safety concerns. More recently the issue was rumoured to be the cause of certain Toyota car models accelerating without the driver depressing the throttle!
My Sky Master is in original condition, so I plan to persevere with it for now, although I may need to replace the transistors at some point.
Ever Ready Sky Master 14/10/2014
One of the more recent additions to my vintage radio collection, an Ever Ready Sky Master dating from approximately 1962. It was in very good condition when I purchased it, although it did need a good clean, and one of the control knobs needed to be repaired. The usual modifications were also necessary in order to accommodate modern batteries.
This set was released after the Ever Ready Sky Leader which I also have in my collection, and is slightly smaller:
The Sky Master continues to work well, and is in daily use, however, it does suffer from a peculiar and interesting issue known as "tin whiskers".
This set contains Mullard's AF series transistors, the construction of which consisted of the junction mounted inside a metallic case, insulated with a silicone grease. Over time very fine tin dendrites grow between the junction and the casing, eventually causing an internal short circuit and loss of operation. The only cure is to replace the transistors, but tapping them with a screw driver breaks the dendrites but they do grow again.
The tin whisker problem had some very serious ramifications, and was studied extensively by NASA as the issue affected the operation of their space craft causing major safety concerns. More recently the issue was rumoured to be the cause of certain Toyota car models accelerating without the driver depressing the throttle!
My Sky Master is in original condition, so I plan to persevere with it for now, although I may need to replace the transistors at some point.