[time-nuts] HP58504A antenna

christopher hoover ch at murgatroid.com
Tue Jul 22 13:07:40 EDT 2008


Bruce wrote:

> Circuit is exactly that to be expected with a discrete pHEMT or similar
> device.
> > It looks to me as if the bias flows through the trace on the BR
> > and then through a couple of 001 R's before the bias
> > setting 221 R.
> >
> >
> Nonsense they are 100 ohm resistors text is upside down.

Ah!  

> > This MMIC is before the filter, so it is probably been selected
> > and biased to avoid IM problems.
> >
> >
> Its unlikely to be an MMIC as they generally have all the bias parts
> internal to the chip other than an output biasing resistor.
> Also most MMICs do not have the input connected to dc ground.

I stand corrected.

-ch





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