Hayward design broadband low noise preamp for loops
In article ,
Fred McKenzie wrote:
The circuit is billed as a broadband amplifier, but low noise is not
mentioned. It is presented as a 24 dB add-on amplifier for a low noise
preamp used in Figure 18.
I found a circuit in a late 70s ARRL Handbook. It is a single stage
identical to each of the two stages in the Antenna Book's Figure 19. I
suspect it is the "Hayward design" you were initially looking for.
The Handbook mentions that the circuit uses negative feedback for wide
bandwidth and unconditional stability. The 2N5179 data sheet indicates
it has low noise.