On Sat, 2007-11-03 at 16:50 -0700, Geoff wrote:
> Hello Bob;
> 
> Have you ever heard of a low noise
> GaAs op amp that is designed to work
> like a op177G (typical opamp) or ??

GaAs FETs go that low in frequency and still yield gain and stability?
Lowest I've ever done is 144MHz and that was straining the chip,
yielding decreased gain (but still higher than any non-GaAs FET).  If my
understanding is correct, GaAs is "saturated" above 2GHz, making them
ideal for microwave LNAs.

Or have I entirely missed the point? :-)

> Signal to noise ratio should be easily found
> in google I think it simply is like
> Expectided MDL signal power / Ubiquitous Noise Power
> The higher the ratio the better the whatever.
> Possibly expressed in db.
> For power thats 10Log(Sig/Noi).

That's mostly accurate:
http://en.wikipedia.org/wiki/Signal-to-noise_ratio


-- 
73, de Brad KB8UYR/6 

__________________________________________________________

Public Seismic Network Mailing List (PSN-L)