Fw: [HEATH-TEMPE] OFF TOPIC QUESTION.

[Bob Groh WA2CKY]

Don't know about the gold grid but they were real. That would have been back in the 1950's and early 1960's as I remember.  They were good for a noise figure (and, boy, this is just off the top of my head) for 2-1/2 or 3 dB noise figure. The 416A was even hotter and more unavailable and I believe it might have been good for NF's down to 2 dB. Both were used in Bell Tel microwave systems. By the early 70's, transistors started to be easily available with NFs much less that that and the day of the tubes was over. Nowadays NFs run down into the 1 dB or better area with low cost transistors. Sigh.

73
Bob Groh, WA2CKY




________________________________
From: Wilson Lamb <infomet at EMBARQMAIL.COM>
To: HEATH at LISTS.TEMPE.GOV
Sent: Monday, November 3, 2008 1:31:35 PM
Subject: Re: [HEATH-TEMPE] OFF TOPIC QUESTION.

Back when Earth was young, everyone wanted WE 417As for vhf preamps.  Does 
anyone know how they compare to a modern SS front end??  Had a gold grid, I 
think.  Was that snake oil?
Wilson
W4BOH
----- Original Message ----- 
From: "Peter A Markavage" <pmarkavage at JUNO.COM>
To: <HEATH at LISTS.TEMPE.GOV>
Sent: Monday, November 03, 2008 12:20 PM
Subject: Re: OFF TOPIC QUESTION.

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