Spurious signals on pan with nothing connected/6700

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  • Updated 2 years ago

With everything disconnected but the power, ground, and network cable I am getting substantial spurs on 80 meters - 4 of them just above the bottom of the band in a sawtooth pattern that are 8Khz apart... the outside 2 are a little weaker than the other 2 but all 4 rise above the noise floor when I do have the RXA antenna connected (HiZ 8 element RX array). Likewise up the band I get another single spur every 63Khz for a large portion of the band. Again not anemic and there when the actual RX antenna is connected. [in both cases the absolute level remains about the same with and without the RX antenna connected so with the RX antenna you can see their 'peaks' coming out of the noise floor]. To state once again this is with NOTHING connected but the ground, power and network. The latter 2 are wound around a decent size core multiple times (and it made no difference in the level before and after). Further this is there whether I'm using the Maestro or SSDR. I'm using 1.10.9.

Help?!

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Gary

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Posted 2 years ago

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George Molnar, KF2T, Elmer

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What frequencies? Can you replace the power supply with a battery, computer with a laptop, and see if they change?
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Gary

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there are actually 5 of these peaks at the low end - the first one is at roughly 3511. They're spaced about 8Khz apart with the center one being the strongest. As for the other signals they're all across the band at 63Khz spacing and look like a carrier signal. I will try a battery - the PS is a SMPS but it is, or I believed it to be quiet and in addition I have a large toroid at the radio with about 8 turns through it. But I'll try a battery.
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Tim - W4TME, Customer Experience Manager

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Can you supply a screen shot of the panadapter?
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Gary

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I'll see if putting it on a battery resolves it in which case its my faux pas ... if not then I'll shoot a screen shot out. Thanks.
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Pat N6PAT

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How this for an example? Flex 6700 on 6 meters with no amp

Config: Windows 8.1, Comet 4 element, LDG 600ProII tuner.  SSDR v1.9.7.169

Check out what happens when I hit the tune button. Then I send a few dots

Here's the video url in case the attached doesn't show well


https://youtu.be/FEOepoR13Ng

Also check out the example for SSB on 6 https://www.youtube.com/watch?v=uRycs_TKMDY&feature=youtu.be

Don't mean to hijack the original compliant. I just though you might like to see some examples of what another Flex owner is experiencing


(Edited)
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Tim - W4TME, Customer Experience Manager

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Pat - Nothing is wrong with your radio based on the video.  That is internal "noise" that is generated during transmit and being picked up by the very sensitive receiver.  Those signals, other than being very low in signal strength (less than -100 dBm) are outside of the final TX filter and are not transmitted.
(Edited)
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Pat N6PAT

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Ok. Thanks for the clarification. FYI I really love this radio. It's a pleasure to operate