ad: M2Ant-1

Yaesu FL-2100B SWR in standby

Discussion in 'Amateur Radio Amplifiers' started by N8VIL, Jan 10, 2016.

ad: L-HROutlet
ad: l-rl
ad: Left-3
ad: L-MFJ
ad: abrind-2
ad: Subscribe
ad: QSOToday-1
ad: Left-2
  1. W1QJ

    W1QJ Ham Member QRZ Page

    That is not what he is saying. If he removes the amp from the line and goes radio to dummy load the swr is good. That is probably what he means.
  2. G3YRO

    G3YRO Ham Member QRZ Page

    Yes but I asked the question to get an idea of exactly what is going on.

    So hopefully he will check the VSWR reading either side of the Amp when in the Standby position, and post the answer . . .
  3. N8VIL

    N8VIL Ham Member QRZ Page

    Now you have me confused. The problem is while in standby (pass through) measured SWR going from the exciter to the amplifier is high on the higher bands (20-15-10) with the amplifier output connected to a 50 ohm dummyload. Out of the amplifier I also have a SWR meter between the amplifier and dummy load measuring SWR just to make sure that the dummy load was showing a perfect match to the amplifier output connector. My goal is to get the SWR as low as possible while in standby (pass through) between the exciter and amplifier.
    I hope to have time here soon to try the capacitor in the circuit to see if that makes a difference.
    Last edited: Jan 16, 2016
  4. AC8AC

    AC8AC Ham Member QRZ Page

    it will fix it the value needed may vary a bit between 20-40pf from the relay cross bar to ground . ive done this quite a few times
  5. W1QJ

    W1QJ Ham Member QRZ Page

    PLEASE, grab a cap between 25 and 35 pf and put it on that shorting bar. That will end this thread.
    N8VIL and WA7PRC like this.
  6. N8VIL

    N8VIL Ham Member QRZ Page

    That's what I am thinking.
  7. N8VIL

    N8VIL Ham Member QRZ Page

    I installed the 33pf cap and greatly reduced pass-through SWR. Going to try a few different values when I get them to tweak it. Thanks for advice on correcting this issue. Thread is closed now. I think we beat this one to death.
  8. W1QJ

    W1QJ Ham Member QRZ Page

    Amen. Some relays never fully null out no matter what value. So get it best you can.
  9. G3YRO

    G3YRO Ham Member QRZ Page

    Yes but as I keep asking . . . WHAT DOES THE SWR READ ON THE OUTPUT OF THE AMPLIFIER when in the Standby position?

    Why won't you answer this question?!

    REASTON QRZ Member

    Maybe he doesn't understand the question as you write it? I am not sure what you are asking either.

    Maybe this is what you mean......"What is the swr of the load (antenna or dummy load) with the swr meter inserted in the coax after the amp's output connector but before the load while the amp is in standby" Is this what you are asking?

    If this is NOT what you are asking then tell us where you want the swr meter placed, exactly, and this is where you want the swr measured from the load.
    Last edited: Jan 17, 2016

Share This Page

ad: elecraft