03-13-2017, 04:13 PM
Steve
I think it was that the el. caps were not really available during the 20-s time. Mershons were used in 70 and that waslater, and they were expensive.
Now if you mean, why not use them today....no electrical reasons why, but:
1. Some folks want to preserve authenticity: in 20 the caps are paper.
2. The caps in 20 are 2uF and in 70/90 are, I believe, 6uF or so. 2uF electrolytic cap is a flimsy creature (well, 6uF is too) and will not take the ripple current. To make a proper 2uF cap that would one would need to serialize bunch of hi-ripple higher capacitance caps. It is easier to do for 6uF, especially considering that most times it is replaced with 10uF value which is easily achieved: I serialize 22uF with high enough ripple to do it.
This said, in a 20 can one easily has the space to place a large film 2uF cap. Makes it easier.
I think it was that the el. caps were not really available during the 20-s time. Mershons were used in 70 and that waslater, and they were expensive.
Now if you mean, why not use them today....no electrical reasons why, but:
1. Some folks want to preserve authenticity: in 20 the caps are paper.
2. The caps in 20 are 2uF and in 70/90 are, I believe, 6uF or so. 2uF electrolytic cap is a flimsy creature (well, 6uF is too) and will not take the ripple current. To make a proper 2uF cap that would one would need to serialize bunch of hi-ripple higher capacitance caps. It is easier to do for 6uF, especially considering that most times it is replaced with 10uF value which is easily achieved: I serialize 22uF with high enough ripple to do it.
This said, in a 20 can one easily has the space to place a large film 2uF cap. Makes it easier.
People who do not drink, do not smoke, do not eat red meat will one day feel really stupid lying there and dying from nothing.
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