[hpsdr] CASMIR Microdesign v3.6

[Alex]

Achim,
I like the Hittite part, but not for the QSE. 
It would be better to replace the PI3B3251s with HMC253QS24s and the PI5V331 after the AD8345/AD8349 with a pair of  HMC241QS16.

Alex, N3NP

----- Original Message ----
From: Achim Vollhardt <avollhar at physik.unizh.ch>
To: harvilchuck at yahoo.com; hpsdr at hpsdr.org
Sent: Friday, July 7, 2006 3:04:45 PM
Subject: Re:[hpsdr] CASMIR Microdesign v3.6

Dear Alex,

I am wondering if the PI5V331 chips are so suitable for UHF and above.. 
why not using hittite switches? They go DC to xx GHz.. depending on the 
one you choose.. for instance 8-fold switch for DC to 2.5 GHZ:

http://www.hittite.com/product_info/product_specs/switches/hmc253qs24.pdf

including 3 to 8 TTL decoder. And: +5V single supply and user friendly 
package (this SMD package still has leads :) )

73s Achim, DH2VA



> Just posted a new CASMIR microdesign (v3.6) as a PDF to 
> http://www.hamsdr.com/personaldirectory.aspx?id=354
>
>Changes include:
>
>(a) Removal of initial PI5V331, AD8132s, and driver amps per Phil's VHDL 
>support of differential I/Q PWM
>(b) Removed issue of no external LO for driving tower mounted amplifiers 
>- 
>port added
>(c) Removed issue of no external amplifier sequencing - connector added
>(d) Revised LO distribution design to reflect design flux
>
>Alex, N3NP





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