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 75 to 50 ohm minimum loss pad

## 75 to 50 ohm minimum loss pad

#1
February 1st 05, 11:23 PM
 J M Noeding Guest Posts: n/a
75 to 50 ohm minimum loss pad

Hi

can't find the notes for a minimum loss pad, anybody who remember the
values? It should be easy to calculate, but I am not in the mood for
doing so at the moment

73
Jan-Martin, LA8AK
---
J. M. Noeding, LA8AK, N-4623 Kristiansand
http://home.online.no/~la8ak/c.htm
#2
February 1st 05, 11:44 PM
 Tim Wescott Guest Posts: n/a

J M Noeding wrote:

Hi

can't find the notes for a minimum loss pad, anybody who remember the
values? It should be easy to calculate, but I am not in the mood for
doing so at the moment

Here. Hot out of the math package. Assuming I know what I'm talking
about it's an L with series 43.3 & shunt 86.6 (theoretical). Should be
6dB of attenuation.

--

Tim Wescott
Wescott Design Services
http://www.wescottdesign.com
#3
February 1st 05, 11:56 PM
 John Popelish Guest Posts: n/a

J M Noeding wrote:

Hi

can't find the notes for a minimum loss pad, anybody who remember the
values? It should be easy to calculate, but I am not in the mood for
doing so at the moment

73
Jan-Martin, LA8AK
---
J. M. Noeding, LA8AK, N-4623 Kristiansand
http://home.online.no/~la8ak/c.htm

Series resistor on 75 ohm side is 43.3 ohms. Parallel resistor on 50
ohm side is 86.6 ohms.

--
John Popelish
#4
February 2nd 05, 12:19 AM
 Dave Platt Guest Posts: n/a

can't find the notes for a minimum loss pad, anybody who remember the
values? It should be easy to calculate, but I am not in the mood for
doing so at the moment

http://www.maxim-ic.com/appnotes.cfm/appnote_number/972

Their calcs yield a design with R1 (in series with the 75-ohm source)
being 43.3 ohms, and R2 (in shunt with the 50-ohm load) being 86.6
ohms.

--
Dave Platt AE6EO
I do _not_ wish to receive unsolicited commercial email, and I will
boycott any company which has the gall to send me such ads!
#5
February 2nd 05, 01:06 AM
 J M Noeding Guest Posts: n/a

On Wed, 02 Feb 2005 00:19:28 -0000, (Dave Platt)
wrote:

can't find the notes for a minimum loss pad, anybody who remember the
values? It should be easy to calculate, but I am not in the mood for
doing so at the moment

http://www.maxim-ic.com/appnotes.cfm/appnote_number/972

Their calcs yield a design with R1 (in series with the 75-ohm source)
being 43.3 ohms, and R2 (in shunt with the 50-ohm load) being 86.6
ohms.

thanks to all, I almost remembered it an hour after asking

73,
Jan-Martin
---
J. M. Noeding, LA8AK, N-4623 Kristiansand
http://home.online.no/~la8ak/c.htm
#6
February 2nd 05, 04:15 AM
 Reg Edwards Guest Posts: n/a

Use program PADMATCH for T, Pi, L and minimum loss pads between any pair of
terminating resistances.
----
.................................................. ..........
Regards from Reg, G4FGQ
http://www.btinternet.com/~g4fgq.regp
.................................................. ..........

#7
February 2nd 05, 08:16 AM
 Ian White, G3SEK Guest Posts: n/a

Tim Wescott wrote:
J M Noeding wrote:

Hi
can't find the notes for a minimum loss pad, anybody who remember
the
values? It should be easy to calculate, but I am not in the mood for
doing so at the moment

Here. Hot out of the math package. Assuming I know what I'm talking
about it's an L with series 43.3 & shunt 86.6 (theoretical). Should be
6dB of attenuation.

Faint bells ring... 43 ohms is a standard value, and 86.6 is pretty
close to 100 paralleled by 680.

For testing 75-ohm TVI filters in a 50-ohm system, it's very handy to

--
73 from Ian G3SEK 'In Practice' columnist for RadCom (RSGB)
http://www.ifwtech.co.uk/g3sek

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