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For the past few days the bands seem unusually quite.

Dalton Williams
Dalton Williams Member ✭
in Community Topics
Friday 6:00 PM August 28 I hear only one station on 40M and none on any other band.
Noise floor with no antenna -113db with antenna -101db
Could I have damaged the radio somehow?
Dalton Williams
W5EIM

Answers

  • VE7ATJ_Don
    VE7ATJ_Don Member ✭✭✭✭
    edited August 2022

    I'm assuming you mean 'quiet'?? :-)

    Anyway, try the radio with a dummy load but the fact there is a difference between antenna and no antenna of approx. 12 db sounds like the radio is OK.

    Are you hearing stations on other bands? Do you have the RF Gain turned down on 40?

  • KD0RC
    KD0RC Member, Super Elmer Moderator

    Hi Dalton,

    On 40 CW at 7:30 PM local time, RF Gain = 0, no antenna (with or without dummy load) I get -125 dBm noise floor on the panadapter (showing 7.000 - 7.075).

    Same conditions but connected to my end fed through a tuner, I get -112 dBm.

    If you dial in more RF Gain, you will see a larger difference between antenna and no-antenna. The goal is to adjust your RF Gain so that you get a 10 or so dB difference. 40 meters should not normally require much RF Gain, and may be best at the -8 dB setting (i.e. 8 dB of attenuation).

    If your antenna is giving you a noise floor of -101 dBm, then you are in an extremely noisy environment, and most of the signals will be covered by noise. The -113 dBm value with no antenna looks like you have -8 dBm RF Gain which would make sense given the high noise level. Have you tried engaging the WNB? I keep mine on at around 30 to **** some garbage that is in my neighborhood.

    Are you by any chance on a vertical? Sometimes, depending on your surroundings, a vert can pick up quite a bit of noise.

  • Dalton Williams
    Dalton Williams Member ✭
    Thanks for your reply.

    Thanks for the suggestion on the WNB. I will read up on how to activate that!!!

    My station is a very folded dipole and a tuner on a boat in downtown Washington DC.
  • KP4IP
    KP4IP Member ✭✭

    @Dalton Williams - How is 40m tonight for you? Last night, I had a NF of S6/7 and very bad propagation. Tonight, my NF is back to S8/9 and I have normal propagation.

  • VE7ATJ_Don
    VE7ATJ_Don Member ✭✭✭✭

    Gee, I thought it was just me in my 'bad' location -- my 40m is typically noise floor of s6-7! Good to know it's happening elsewhere as well!

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