[hpsdr] Proposal for a 'low-end' RX/TX board for HPSDR

[Ahti Aintila]

> Ahti,
>
> Here is another circuit to look at:
>
> <http://www.philcovington.com/HPSDR/TEMP_STUFF/isd_07282006-1.pdf>
>
> Using a quad op amp reduces the component count even further and there
> is still differential output.
>
> 73 de Phil N8VB
>

Congrats Phil!

Now you made it! I cannot put it any better component count-wise.
LT1127 seems to have somewhat higher noise (4.2nV/sqrt Hz) than the
earlier suggestions. Maybe, there is still use for OPA1632 (or better)
 in more demanding applications.

73, Ahti OH2RZ

 1154103790.0