[Date Prev][Date Next][Thread Prev][Thread Next] - [Date Index][Thread Index][Author Index]

Re: attenuator construction questions-and the winner is...

I built an attenuator with the information below.  The only pot I had was 
25k, and it works well enough that I may not replace it...how nice to have 
an S0/S1 noise level now! :)

Thanks for all the great replies/responses to my inquiry.


Mark N8MH

At 12:31 PM 9/8/2001, Alex Artieda HB9DRI wrote:
>Hi Mark:
>This is a very simple variable attenuator, provide +- 20 db variable, I used
>in my 144 down converter and is posible to adjust the noise 0 to S9+, its
>very good to adjust your S meter. Consit in a PI configuration, you need:
>2 resistor 220 ohms (1/4 watt is ok, 1/8 also)
>1 trimmer or potenciometer 1 kilohm (1000 ohms)
>- place both resistor with one side solder to ground, the other sides open.
>-place the 1000 ohms trimmer in series with the other free sides of both
>resistor, remember the trimmer have 3 conections and you need to solder a
>small cable to shor two connections, the center tap with one side tap.
>-One point is the input were you solder the 220 ohms open side with one side
>of the trimmer, the other side is the output
>The impedance is 50 ohms and work fine, sorry my explanation but English is
>not mi language, if you dont understand tell me and I prepare a draw for
>73 DX

Mark L. Hammond  [N8MH]

Via the amsat-bb mailing list at AMSAT.ORG courtesy of AMSAT-NA.
To unsubscribe, send "unsubscribe amsat-bb" to Majordomo@amsat.org