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Spurious RF Spikes on Every Band

Randall Steffens II
Randall Steffens II Member
edited June 2020 in FLEX-6000 Signature Series
Hi All, I just got my flex 6300 and I'm having strange spurious RF spikes on every band. I inserted a few pictures below.  Does this look like a power supply problem?  I'm using the MFJ 4230MVP switching power supply.  I don't have ferrites on anything yet, would that help?

I'm using a 60 foot center fed dipole fed with 450 ohm ladder line. And an old MFJ-941C manual tuner because the internal flex autotuner can't handle this antenna.  The birdies get much smaller or even disappear on most bands when I fully “detune” the antenna with the manual tuner.  But when tuned, there are tremendous spikes in every band as shown in the photos below.

One problem may be that I live in an apartment and cannot connect any RF/AC ground to the radio.  The switching power supply is grounded through the AC wall plug, but nothing else so far.

 If you'd be so kind, take a look at the screenshots below and let me know your thoughts.  Some bands it's less obvious than below, but this pattern is visible to a greater or lesser degree on every band once that band is tuned. 

Thanks! Randy Steffens


image

image

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Comments

  • Mike
    Mike Member ✭✭
    edited February 2019
    That looks like a cheap Chinese power supply. I would start unplugging things and see if it disappears
  • Steve WS5W
    Steve WS5W Member ✭✭
    edited April 2020
  • Randall Steffens II
    Randall Steffens II Member
    edited December 2018
    Yeah, it was cheep. But it had good reviews on Amazon and eham!  I'll see if I can turn off my breakers and isolate if anything else in my apartment could be causing this. 
  • WK2Y
    WK2Y Member ✭✭
    edited December 2018
    Try running on a battery if you can.  In receive, the Flex doesn't draw much current.
    That will clearly identify if the power supply is the culprit.


  • Steve WS5W
    Steve WS5W Member ✭✭
    edited April 2020
  • Steve WS5W
    Steve WS5W Member ✭✭
    edited April 2020
  • Ken - NM9P
    Ken - NM9P Member ✭✭✭
    edited June 2020
    The MFJ PS is usually pretty clean so my bet is some other power supply. That particular pattern looks like my wife’s laptop computer power supply.

    Someone from Flex, either Tim or Dudley, once told me: “ The great thing about the SDR is that you can see everything on the band. The bad thing is that you can see EVERYTHING on the band — even all the crud that you never noticed on a legacy rig. “

    You will find that you now can see exactly why electronic pollution is a big issue for a lot of folks!
  • Dave - WB5NHL
    Dave - WB5NHL Member ✭✭
    edited February 2019
  • Randall Steffens II
    Randall Steffens II Member
    edited December 2018
    It's approx.  every 40 kilohertz or so.

    I'll check the site!  Thank you!

    Randy


  • Randall Steffens II
    Randall Steffens II Member
    edited December 2018
    Very interesting Ken.  Thanks for the feedback.  I'll see what I can unplug - then test again.
    Randy
  • Randall Steffens II
    Randall Steffens II Member
    edited December 2018
    Thanks for the recommendations Steve. Would an RTL-SDR work as well for this purpose as the SDRPlay?  It's significantly cheeper! 

    Thanks!
    Randy

  • Randall Steffens II
    Randall Steffens II Member
    edited December 2018
    I'll see if I can use my car battery to test it out.  

    Thanks!
    Randy
  • Steve WS5W
    Steve WS5W Member ✭✭
    edited December 2018
    If it does HF, I dont remember how low it goes.

  • Bob G W1GLV
    Bob G W1GLV Member ✭✭
    edited June 2020
    My air conditioner produces those spikes when it's running. Had to install a filter to get rid of them. I live in Florida.
  • Rhett Aultman
    Rhett Aultman Member ✭✭
    edited December 2018
    My cable modem throws off birdies, so I've been looking for something like this.
  • Michael Coslo
    Michael Coslo Member ✭✭
    edited February 2019
  • Andy - KU7T
    Andy - KU7T Member ✭✭
    edited February 2019
    My heat pump does exactly that. Make sure you turn that one off first and verify (I guess flipping breakers will force you to do that). It maybe your neighbor's too. Andy KU7T
  • Randall Steffens II
    Randall Steffens II Member
    edited December 2018
    Yes, very useful!  Thanks!
  • Randall Steffens II
    Randall Steffens II Member
    edited December 2018
    I'll definitely check that.  Thanks for the suggestion Bob!
    Randy
  • Randall Steffens II
    Randall Steffens II Member
    edited December 2018
    I'll check on that.  Thanks for the suggestion!
    Randy
  • Randall Steffens II
    Randall Steffens II Member
    edited December 2018
    Ok - I'll try that.  Do I reset by pressing the power button on the radio until the blinking white light appears?
    Randy
  • David Ahrendts
    David Ahrendts Member ✭✭
    edited February 2019
  • Craig Williams
    Craig Williams Member ✭✭
    edited December 2018
    Nice link, thanks.
  • Craig Williams
    Craig Williams Member ✭✭
    edited December 2018
    I bet if you put one of these in a grounded metal box it would help. Also torroid's on all the control cables. https://enerdoor.com/products/view/fin33-single-phase-rfi-filter 
  • Randall Steffens II
    Randall Steffens II Member
    edited December 2018
    What a useful post!  Thank you David!  I really appreciate this advice.
    Randy
  • Dave - WB5NHL
    Dave - WB5NHL Member ✭✭
    edited December 2018
    At this rate I'd be looking for a poorly filtered switching power supply or wallwart. Good luck   let us know what you find.
  • Vox Deus
    Vox Deus Member
    edited December 2018
    Yup.
  • Randall Steffens II
    Randall Steffens II Member
    edited April 2019
  • Stan VA7NF
    Stan VA7NF Member ✭✭✭
    edited April 2019
  • Randall Steffens II
    Randall Steffens II Member
    edited April 2019
    Thanks for the reply! What material did you read to get details on how to build the wire loop? I see a lot on google, but if there are any particular books or websites you’d recommend on the subject, that would be great to know. Thanks again, Randy

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