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Topics - IQ_imbalance

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Equipment / RF circuit help....
« on: June 12, 2020, 0219 UTC »
Hi all.  I purchased a diplexer so i could run a VHF and a UHF antenna into the same feedline.  Seems to work well, but I didn't notice that there's a gap between the two bandpasses (VHF 47-230 MHz, UHF 470-862 MHz).  Unfortunately there's a 350 MHz system i'd like to receive, so I'm wondering if i can tweak the circuit to fix this...ideally by shifting the VHF bandpass from 47-230 MHz to 47-400 MHz (or thereabouts). 

I did my best to trace the circuit (damn tiny surface mount components!!!)  Can anyone make heads or tails of this, and suggest somewhere i might start to try and figure out how to modify the VHF bandpass?  I'm fine w/ the UHF settings, so hopefully i just have to do something to the VHF leg.

Equipment / Up the discone!!
« on: May 15, 2020, 0010 UTC »
Today I started my little project to get some elevation on my DJ-130 discone.  Itís been mounted on a 2nd floor deck, but I want to try and raise it above the roofline if possible.

Its new home will be a tree so I broke out the fishing pole, lead sinker, and slingshot. I was pleasantly surprised to manage to get the line on a decent branch without the lead sinker breaking any windows or heads.  So far so good....

Next was to swap the 20lb test for something more substantial.  Unfortunately the 550 cord I thought I had was nowhere to be found beyond bits and pieces, but nowhere near the length necessary.  Amazon to the rescue, but that means itís in a holding pattern for now.

Equipment / fun toys (digital multimeters/oscilloscopes)
« on: May 12, 2020, 1918 UTC »
Just putting this here....i'm a fan of things that leverage the damn expensive hardware i carry in my pocket...

North American Shortwave Pirate / UNID 6955 USB 0205 UTC 08 Dec 2019
« on: December 08, 2019, 0212 UTC »
S3-S5.  SIO 444.
0205: Stray Cats Rock this Town
(another stray cats song, then some metal...)
0210: rap
0211: Popeye twist.  still SIO 444.
0213: guitar instrumental..Parisiene Walkways?
0216: Radio Ga Ga
0218: OTA

HF Mystery Signals / 7335 and 7365kHz CW? 20191116 0216 UTC to ???
« on: November 16, 2019, 1614 UTC »
Maybe CW?  Broadcast on 7335 and 7365 kHz 20191116 0216 UTC until ?????.  Captured from central MD, but also noted on Kiwis across eastern US (didn't check western US).  TDoA suggested SE US, maybe Florida....

Someone on HF chat commented that these are Radio Marti freqs.....

There's a company that benchmarks and assembles desktops based on intended software use....


0323 UTC:  news story about longline fishing negotiations
0329 UTC:  music
S2-3; SIO 333.  Pretty amazed that it's coming in this well! 

HF Mystery Signals / UNID pips ~ 14220kHz 1337 UTC 7 June 2019
« on: June 08, 2019, 1806 UTC »
These came up at multiple frequencies (although I don't recall if they were concurrent) on the morning of 7 June.  Interesting thing is the train on a frequency would cycle up in magnitude and back down again....maybe a directional antenna sweeping around? 

2008 UTC AC/DC Hells Bells...right at QRN. SIO 222, brief bump up to SIO 333
2011 UTC AC/DC Shoot to Thrill
2016 UTC AC/DC ???
2019 UTC off?

1643 UTC:  Irish music.  S1-S2, SIO 344.
1645 UTC: ID as Irish Rose Radio
1651 UTC:  off the air due to banshees
1657 UTC: back on the air?
1703 UTC:  S2-S3 w/more Irish music.

started off as carrier only, now instrumental music  SIO 333.
1630 UTC:  back to just a carrier with the occasional hint of music.
1634 UTC: switched to the loop and got slightly better reception.  some peaks at S2.
1708 UTC: off

0035: Sweet home Alabma  -137dBm, fades to QRN

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