03-09-2013, 07:14 AM
I don't think the code number ever changed in production of the 40-150 and 40-155, but yes, the oscillator tube changed - not once, but twice.
Originally these used a 7J7. Then Philco switched to a 6J8G. Later on, they switched back to a 7J7. Same applies to the 40-180, 185, and 190.
If you look in a tube data book or online such as here:
http://www.nj7p.info/Common/Tube/SQL/Tube.php
you will see that the 7J7 and 6J8G are essentially identical electrically, but one is loctal and one is octal with a grid cap, and the pinouts (and sockets) are different.
Beware the oscillator tube socket in these models. It is made of that light tan material that is very delicate, very fragile, and very prone to failure, breakage, etc. I don't know why Philco did that, maybe that stuff is a low loss material compared to the normal brown wafer used in other sockets? I've replaced these with brown wafer sockets from junk Philco sets and did not have any problems afterwards.
Originally these used a 7J7. Then Philco switched to a 6J8G. Later on, they switched back to a 7J7. Same applies to the 40-180, 185, and 190.
If you look in a tube data book or online such as here:
http://www.nj7p.info/Common/Tube/SQL/Tube.php
you will see that the 7J7 and 6J8G are essentially identical electrically, but one is loctal and one is octal with a grid cap, and the pinouts (and sockets) are different.
Beware the oscillator tube socket in these models. It is made of that light tan material that is very delicate, very fragile, and very prone to failure, breakage, etc. I don't know why Philco did that, maybe that stuff is a low loss material compared to the normal brown wafer used in other sockets? I've replaced these with brown wafer sockets from junk Philco sets and did not have any problems afterwards.
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Ron Ramirez
Ferdinand IN
