Ooops - sorry. I mistook the alignment ‘+’ for the polarity.
Terms like “wide band” mean different things to different people. In this case the author is interested in HF (< 30MHz), so the design (even if it worked properly) - as you say, would be useless at 1090MHz.
Looking at the BG7TBL Nose Source (mine it yet to produce it’s first nose), I just had a poke with a multimeter (Fluke 17b+).
Mine is the: 2016-03-06 with the BB5Z MIMIC’s (SBB-5089)
I set the input to: 12.00V (233mA)
Voltage drop across D2: 0.63V
I then measured the supply each MIMIC (w/ 50Ω load) at junctions of:
U2: R8/L6 - 4.73V
U3: R9/L7 - 4.82V
U4: R10/L8 - 4.66V
The Spec sheet gives Vmax as 5.5V.
I had to wind up the PSU to 16.5V to get 5.5V on the first MIMIC (U3)
Several people report these ‘noise sources’ run hot, but based on the measurements above, I’d guess one of the following:
- The MIMICs are non-genuine (ie. not as per the data sheet)
- The 12V PSU/Wall Wart etc. is putting out a lot more the 12V - Time for a new one.
Edit: I’ve had mine powered up for half an hour. While it’s getting warm, the 100Ω dropping resistors (R8, R9, R10) are hotter than the amplifiers.