Strong Birdies in 75/80M

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Kriss - KA1GJU
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Joined: Sat Feb 29, 2020 2:10 pm

Strong Birdies in 75/80M

Post by Kriss - KA1GJU »

I thought it was from my temporary desktop, but it appears it's within my 200D. It's a steady S-8 (-79dBm) at about 3938.5kHz and ever so slowly drifts low in frequency. I found a few more similar ones, on 2624kHz, 3283kHz and 4591kHz.

Any thoughts as to a remedy? Screenshots are attached.

Thank you,
73 Kriss KA1GJU
Attachments
UpClose.png
UpClose.png (932.8 KiB) Viewed 4689 times
Antenna.png
Antenna.png (888.64 KiB) Viewed 4689 times
DummyLoad.png
DummyLoad.png (834.99 KiB) Viewed 4689 times
PD3LK
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Joined: Mon Nov 11, 2019 8:45 pm
Location: Apeldoorn, NLD

Re: Strong Birdies in 75/80M

Post by PD3LK »

Hi, if you have the 6m pre-amp on then try to set it off. It helped me with my 7000
r/Leon
73 PD3LK Leon
Kriss - KA1GJU
Posts: 3
Joined: Sat Feb 29, 2020 2:10 pm

Re: Strong Birdies in 75/80M

Post by Kriss - KA1GJU »

Turned 6M pre-amp off, no change. :cry:
Thanks for reply though!
73 Kriss KA1GJU
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w-u-2-o
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Joined: Fri Mar 10, 2017 1:47 pm

Re: Strong Birdies in 75/80M

Post by w-u-2-o »

Moved: not an SDR Console topic.
Kriss - KA1GJU
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Joined: Sat Feb 29, 2020 2:10 pm

Re: Strong Birdies in 75/80M

Post by Kriss - KA1GJU »

OOPS! Sorry about posting in wrong location. Not used to this forum, I'm more of a Groups.io guy.
Anyway... any ideas from the folks here? Do all 200D's exhibit this behavior?

Here's the version:
ver.png
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73 Kriss KA1GJU
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w-u-2-o
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Re: Strong Birdies in 75/80M

Post by w-u-2-o »

The 6M preamp will have no bearing on this problem given that it is on 80M.

As far as I know, nobody has ever experienced an S9 birdie (internally generated spur).

I see you have run the unit into a dummy load. Have you also tried running the unit off a battery instead of a power supply?
G3ZQH
Posts: 111
Joined: Mon Apr 10, 2017 5:21 pm

Re: Strong Birdies in 75/80M

Post by G3ZQH »

On my 200D I do not see any of these spurs with a dummy load in place. There are no spurious emissions at all that I can see in this range. Peaks of that size are more likely to come externally rather than from the rig. Or possibly a fault in the rig?
73 Dave G3ZQH
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