[Radioroslyn]

You may remember last fall I picked up a Crosley Tridyn at Kutztown and gave a blow by blow discripiton of it's repair.
http://www.philcoradio.com/phorum/showth...p?tid=7614
Well this spring I picked up another Crosley a model 51. The 51 is very kewl set two tubes but will drive a speaker listening to local stations. This pretty amazing for a 1924 set using 201A tubes.
Back then it was available in four different versions, plain https://www.google.com/search?q=Crosley+...B750%3B418 special, https://www.google.com/search?q=Crosley+...B480%3B360 ,special deluxe https://www.google.com/search?q=Crosley+...B480%3B360, and portable https://www.google.com/search?q=Crosley+...B429%3B374 . If you closely at the portable the panel layout is different that because the set is a early versinn Mine is the deluxe. What that means is it has a larger cabinet so the batteries can be stored inside.
One of the thing Powell Crosley was famous for was designing the book tuning condenser. Crosley was set on making radio affordable for the masses. One of the more expensive parts was the tuning condenser. Most then where made of brass or aluminum and required machining to fabricate. The book condenser used two squares of Bakelite with a thin metal plate covering one side of each of them. A hinge was added so the distance between the two plates could be varied. Two springs and a cam were used to adjust the capacitance (the spacing between the two plates) And there was a thin insulator between the two plates so they wouldn't short. You can see one here on the right side of this model 50 chassis.
https://www.google.com/search?q=Crosley+...B640%3B543
As for expense of the set the plain version sold for $18 less tubes and batteries. Covers the AMBCB and a little extra in five steps. One of the 201A's is a regenrative detector and the other is the audio amplifier.
More Later
Terry