[hpsdr] Penelope External Control

[Sheldon Hands]

----- Original Message ----- 
From: "Bill Tracey" <bill at ewjt.com>
To: "Brian Crighton" <m5bjcc at ntlworld.com>; <hpsdr at hpsdr.org>
Sent: Monday, January 26, 2009 5:54 AM
Subject: Re: [hpsdr] Penelope External Control


> ***** High Performance Software Defined Radio Discussion List *****
>
> You've lost me.  How are you controlling the filters - I'm not sure I 
> understand what the control path is?
>
> Regards,
>
> Bill (kd5tfd)


I might have the same problem. I´m planning to use one of my old QRP PA 
designs which has a ULN2003 as a pulll down to a  BC640 high side switchs 
for the LPF relays. I intend to remove the ULN on the amp board and use the 
one on Penelope to drive the switches.

The 7 control lines are fine  for me as its a six set LPF to cover to 10mtrs 
with some high bands doubled up.

The main question though is if you select a non ham band does one of the 
open collectors default to the 10mtr or highest output? At least this way 
Merc could see any thing under the highest LPF frequency.

Curently I have the AMP control hard wired for testing. The AMP is a single 
VN66AFD driving another pair. I get 5 watts out with the default drive from 
Penolpe  and it drives drives one of my Bipolar Motorola AN bricks to around 
100W .

I had planed to change the driver amp LPF to HPF but will have to think 
about this again if I want general coverage as well.

None of this is really a problem as Alex will solve all these issues.


Shel CT1IZU



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