dykesc wrote:
I am trying to validate impedance values I am measuring with my
MFJ-259B. I want to do this by using my MFJ-993B auto tuner. The tuner
uses a simple L network to create the conjugate match. I want to take
the final inductance, capacitance and swr values from the auto tuner
digital display after matching is completed and back calculate the
impedance that the tuner is seeing. Is there an online calculator that
will do this?

Many thanks for replys.

http://ytdp.ee.wits.ac.za/smithchart.pdf

http://www.dxzone.com/cgi-bin/dir/jump2.cgi?ID=8763

On Jun 3, 2:17*pm, dave wrote:

http://ytdp.ee.wits.ac.za/smithchart.pdf

http://www.dxzone.com/cgi-bin/dir/jump2.cgi?ID=8763

I don't run Linux Dave. Is there a Windows version? Meanwhile I am
going at it manually with a Smith Chart. At multiple frequencies this
will take some time.

Dykes AD5VS

dykesc wrote:
On Jun 3, 2:17 pm, dave wrote:

http://ytdp.ee.wits.ac.za/smithchart.pdf

http://www.dxzone.com/cgi-bin/dir/jump2.cgi?ID=8763

I don't run Linux Dave. Is there a Windows version? Meanwhile I am
going at it manually with a Smith Chart. At multiple frequencies this
will take some time.

Dykes AD5VS


you can do it with an Excel Spreadsheet..

You know that at "match" the impedance looking into the tuner from the
antenna is the conjugate of the impedance looking into the antenna from
the tuner.

If you assume your transmitter is 50+j0 ohms (not a good assumption..
but you could make it closer to being so by putting a 10dB pad between
Tx and tuner, for instance)

Then, you calculate what the impedance the tuner is using the L and C
values (I assume it's a series L and a shunt C) ... you'll either have:

TxR plus L, shunted by C
or TxRshunted by C, then series L

A spreadsheet like XLZIZL does it in a flash.

On Jun 4, 11:09*am, Jim Lux wrote:

you can do it with an Excel Spreadsheet..

A spreadsheet like XLZIZL does it in a flash.

Thanks Jim. I found and downloaded XLZIZL

73
Dykes AD5VS

dykesc wrote:
On Jun 3, 2:17 pm, dave wrote:

http://ytdp.ee.wits.ac.za/smithchart.pdf

http://www.dxzone.com/cgi-bin/dir/jump2.cgi?ID=8763

I don't run Linux Dave. Is there a Windows version? Meanwhile I am
going at it manually with a Smith Chart. At multiple frequencies this
will take some time.

Dykes AD5VS


RF Cafe has one that uses Excel. www.rfcafe.com

On Jun 4, 2:13*pm, dave wrote:

RF Cafe has one that uses Excel. *www.rfcafe.com

Thanks Dave. I just downloaded it.