Phasing Transformer Question

Discussion in 'The Projects Forum' started by Clint KY, Oct 15, 2011.

  1. Clint KY

    Thread Starter New Member

    Oct 15, 2011
    3
    0
    I built a trifilar phasing transformer to feed two identical vertical antennas and to be able to switch one output so as to feed the antennas either in-phase or out-of-phase. Well the transformer works as I thought it would as far as the phasing goes BUT when I look at the outputs of the secondaries In-Phase they are the same amplitude and when I reverse one test lead of my oscilloscope the amplitude of the inverted signal is half the other. I have checked my connections and all are fine. What am I missing?

    Clint - W5CPT -
    Far West Kentucky
     
  2. Kermit2

    AAC Fanatic!

    Feb 5, 2010
    3,788
    945
    Why are you reversing the scope leads at all? Putting the scope ground clip on a circuit point with a voltage other than ground will provide a path to ground for the circuit at that point, unless you have your scope AC power isolated with an isolation power transformer.

    Do you have the scope AC power isolated from AC mains ground?

    A picture is truly worth 1000 words here. You will get more responses if others can SEE what you are doing vs. having to decode your verbal description of the circuit connections.
     
  3. Clint KY

    Thread Starter New Member

    Oct 15, 2011
    3
    0
    I have added a schematic below. The input is on the left and the fixed output is the top one on the right. The second (lower) output is fed through a DPDT switch (relay) with a revering setup to change the phase of the signal going to that particular antenna. When the switch is thrown to put the signal Out-Of-Phase with the fixed input the scope shows the expected phase reversal, but the output is fully half of the fixed output.

    I hope that clarifies my dilemma.

    Thanks,
    Clint in KY
     
  4. Clint KY

    Thread Starter New Member

    Oct 15, 2011
    3
    0
    Never mind. It appears that I have more going on than I originally thought. Measuring the two secondaries shows one puts out almost as much as I am putting in on the primary while the other is about half of that. A resistance check shows so close to 0 ohms for all three so no help there. I will have to get some better wire and rewind it. Thanks for the input so far.

    Clint
     
Loading...