On 2 mar, 16:06, "Teri Buck" wrote:
I am using a multi-switch to change radios and antennas. One of those MFJ
1700Bs. I get different SWR readings depending upon where I place the
bridge in the tangle of wires that go into and out of the switch. If I
take the switch out of the equation I get very low SWR. With it in I get
2.5:1.

Hello Teri,

It is very likely a common mode problem (as Danny and Richard also
mentioned).

Sometimes the SWR meter is the problem. Check your instrument by
connecting a known mismatched with various length of cable (for
example 75 Ohms resistor in combination with 2 1/8 wave 50 Ohms
cables). This resistor should give a 1.5 reading on the instrument,
irrespective of cable length between resistor and instrument (provided
that cable losses can be neglected).

Other problem (unlikely) can be significant harmonics in the output of
your Final Amplifier.

Best regards,
Wim
PA3DJS