Making your own 20 db attenuator
Making your own 20 db attenuator
(OP)
I want to make my own attenuator - would this work or what should I change?
/-------100 ohm resistor-------ground
/
input----/
\
\
\-------1 ohm resistor--------output
i will make each lead length = wavelength/2
is it do-able like this?
:)
/-------100 ohm resistor-------ground
/
input----/
\
\
\-------1 ohm resistor--------output
i will make each lead length = wavelength/2
is it do-able like this?
:)





RE: Making your own 20 db attenuator
You should look up Pi and T attenuator circuits. There are plenty of on-line calculators. You'll need to specify your input and output Z.
RE: Making your own 20 db attenuator
Or perhaps use a length of lossy cable (if your application can accept the delay).
RE: Making your own 20 db attenuator
Strip two cable ends having the center conductors poke out of the cables, and place cables near each other. If you make them about 1/4 wavelength center conductors you may get good VSWR on your attenuator.
Put them in a box to stop leakage. you can have from about 6 dB up to 40 dB attenuator ranges. You could probably put them in a metal box and make some slide mechanism or tuning screw arrangement to move them apart and set your attenuation level if you're mechanically clever.
One long cable with loss is another way to make an attenuator. It has very good VSWR too.
kch
PS: Attenuators with resitors always require 3 of them to make a X dB attenuator and maintain good VSWR. Two in series with one to ground (T type), or one in series and two to ground (Pi type). Search Resistive T or Resistive Pi attenuator and you'll find good details. I don't suggest trying this though with normal attenuators, usually companies make a tiny package that you insert into a microstrip package.
RE: Making your own 20 db attenuator
I had a college looking for a similar thing not to recently.
RE: Making your own 20 db attenuator
You can buy thin-film PI resistor attenuators on a chip for reasonable cost. Check out the Panasonic EXB24A series and the Susumu PAT series at Digikey's web site.
RE: Making your own 20 db attenuator
5-1000MHz antenuators can be had for as little as 3 bucks (Note these are ultra cheap and I would not use them for accuracy) for coax applications with 250 buying a set of good quality attenuators.
RE: Making your own 20 db attenuator
RE: Making your own 20 db attenuator
let see....58' of rg-58 loses 20 db!
thanks Higgler, IOU one!
RE: Making your own 20 db attenuator
Sniff.
[!!!!
RE: Making your own 20 db attenuator
:)