[Hallicrafters] Re: Blue glowing tube rectifier???

[krk at ix.netcom.com]

Cal,

  Interesting that you have an 83 in your 28. The 83 is a mercury vapor rectifier and 
my tube substitution data indicates that it is a valid substitute for a 5Z3 (as is a 1275). 
I would expect a bluish glow from an 83 (but not a 5Z3). I think the main value of a 
mercury vapor rectifier is low internal voltage drop (about 15 volts) compared to the 
vacuum type rectifier (up to 58 volts for a 5Z3). This probably means that your B+ is 
a little high. You might check it. It would be almost (but not quite) like using solid-
state (shudder) rectifiers.

  Other than that, isn't the 28 a great radio? Who to believe? I believe your Hickok, 
your 28 and you. Hey, blue is my favorite color...

Regards,
Ken

> All: My SX-28's 5Z3/83 tube has a bluish tinge to it. According to the AN/GRR-2
> manual, it says that a blue glowing rectifier is faulty and should be replaced.
> My tube tester, a Hickok 505, says the 83 is fine and reads above specs. The
> radio certainly operates o.k. Who to believe? Many thanks. Cal.