[Johnson] 3B25

[Roy Morgan]

At 06:12 PM 2/22/02 -0800, you wrote:
>My data from 1955 ARRL handbook does not show a Max AC Plate Voltage per
>Plate... just a dash in that category.
>
>Peak Inverse voltage rating is lower than 3B28... and that is critical.

See the following link for some data (summary data):
<http://www.wps.com/archives/tube-datasheets/Datasheets/CBS-Bulletin-E-290C/8.JPG>


The 3B25 max ac supply volts plate to plate is 3000 at average amperes 0.5
Same for the 3B28 is 3500 at average amperes 0.5
Same for the 3B28 is 7000 at average amperes 0.25

Sibley's book "Tube Lore" indicates that the 3B28 was introduced a couple 
of years after the 3B25.  I suspect that the 3B28 simply replaced the 
earlier one.

Roy


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