12-16-2009, 08:47 AM
Philco never published a schematic of the 40-180 showing the 6J8G tube. You have to use the schematic showing the 7J7, and have a layout of the 6J8G connections handy.
The internal elements of the 7J7 and 6J8G are identical, and would appear so on the schematic if two versions existed (one showing a 7J7 and one showing a 6J8G). It is only where the elements connect to the individual pins (and grid cap in the case of the 6J8G) that differ. Both are triode-heptode converters.
I prefer the NJ7P tube database, results are below.
7J7: http://www.nj7p.org/Tube4.php?tube=7J7
6J8G: http://www.nj7p.org/Tube4.php?tube=6J8G
Notice that they are electrically identical - specifications are the same - and each tube contains a triode and a heptode in the same glass envelope! Again, the difference is in the pin layout.
The internal elements of the 7J7 and 6J8G are identical, and would appear so on the schematic if two versions existed (one showing a 7J7 and one showing a 6J8G). It is only where the elements connect to the individual pins (and grid cap in the case of the 6J8G) that differ. Both are triode-heptode converters.
I prefer the NJ7P tube database, results are below.
7J7: http://www.nj7p.org/Tube4.php?tube=7J7
6J8G: http://www.nj7p.org/Tube4.php?tube=6J8G
Notice that they are electrically identical - specifications are the same - and each tube contains a triode and a heptode in the same glass envelope! Again, the difference is in the pin layout.
--
Ron Ramirez
Ferdinand IN
