Friday, October 07, 2016
Why transistors succeeded
Not relevant to anything, just a number that struck me while binge-reading old electronics mags.
The tube-based portable on left is typical of the breed. Six tubes plus a bunch of resistors, capacitors, and transformers.
When transistors first came on the market, Raytheon owned the niche. The CK722, more or less the default germanium transistor, was $3.10 retail. What was the advantage?
Price? Nope. The price list on right shows the types of tubes that would have been used in this portable. All in the same range as the CK722.
Size? Nope. Those early transistors were limited in their amplifying and power-handling ability, and a circuit often required two or three trannies, plus some extra resistors and so on, to replace one tube. Net size of components about the same.
The one number that tells the story is 8 POUNDS LESS BATTERIES. Tubes needed more space and a heavier chassis and (some) heavier components because they used higher voltages and generated more heat. The batteries would have added another 3 or 4 pounds.
¶ 12:54 AM 
The tube-based portable on left is typical of the breed. Six tubes plus a bunch of resistors, capacitors, and transformers.
When transistors first came on the market, Raytheon owned the niche. The CK722, more or less the default germanium transistor, was $3.10 retail. What was the advantage?
Price? Nope. The price list on right shows the types of tubes that would have been used in this portable. All in the same range as the CK722.
Size? Nope. Those early transistors were limited in their amplifying and power-handling ability, and a circuit often required two or three trannies, plus some extra resistors and so on, to replace one tube. Net size of components about the same.
The one number that tells the story is 8 POUNDS LESS BATTERIES. Tubes needed more space and a heavier chassis and (some) heavier components because they used higher voltages and generated more heat. The batteries would have added another 3 or 4 pounds.
¶ 12:54 AM
