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Messages - IQ_imbalance

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General Radio Discussion / Re: Russian Kerosene Powered Radio
« on: July 07, 2020, 1220 UTC »
Kerosene?  Bah!  In modern Russia the mighty atom powers all! 

Maybe these folks were just looking for a new radio 'battery'...

Equipment / Re: Garbage Baluns
« on: July 06, 2020, 2339 UTC »
That's my ~ 40' diameter loop on ground.  Using a squid balun since my little chinese 1:9 was flooded out :)

Note that's the SWR reading where my feedline comes into the house, so that's the antenna plus a whole bunch of buried RG-6/U.

Equipment / Re: Garbage Baluns
« on: July 06, 2020, 1901 UTC »
Sooo...would this be an OK result for a broadband HF receive only antenna (at least above 1.4MHz or so)?  Note the scale....looks like the SWR is 1.2-2.0 above 1.4MHz.  The max SWR is ~8 on about 800kHz.

And it has a big horn!

Too bad itís just for elders....

Equipment / Re: Antenna projects that were not successful
« on: June 27, 2020, 1626 UTC »
Well, my first attempt at a VHF/UHF diplexer didnít turn out too well.  The calculations and simulation was for a crossover freq of 500 MHz.  As you can see, that didnít happen!  I think the inductors I wound were the issue, so will give it another shot.

The RF Workbench / Re: dumb soldering question of the day
« on: June 23, 2020, 1510 UTC »
Thanks!  Now that I've got a VNA i'm putting a toe into the 'brew your own RF filter' water.  On the plus side...i've gotten good with some of the simulation software, and the filter i cobbled together works after a fashion.  On the minus side....the simulations and real life frequency cutoffs are very different, i suspect due to my half-ass attempt at making coils.  Still...progress!

The RF Workbench / dumb soldering question of the day
« on: June 22, 2020, 1958 UTC »
Any tips on soldering female F-connectors, esp. to the body?  I'm spitballing a RF filter circuit before i start cutting on my last mint tin.....

SDR - Software Defined Radio / Re: RPi Ethernet question
« on: June 21, 2020, 2150 UTC »
Finally got it to work.  After messing around with static IPs, etc. just had to set relative priorities for WiFi and ethernet and let DHCP do its thing.

Now...if i can get the rtsp/rtp stream into icecast2...... 


5790 AM:  can see carrier but no audio.
6170 AM: nothing observed.
7360 AM:  noisy, strongest reception (2-4 dBm). 
9580 AM, weak mostly <1.5dBm.

I've got it on 9580 but very weak.  Can make out voices but no intelligible copy.

SDR - Software Defined Radio / Re: RPi Ethernet question
« on: June 21, 2020, 1345 UTC »
Yep...direct connection.  The idea is to use an instance of icecast running on the RPi to stream the deviceís (itís a radio btw) audio wirelessly.

You being up a good point...while the Ethernet port on the RPi should autosense (theyíve done that for awhile) itís possible something is wonky there.  Wouldnít matter on the Mac since it would take up the slack, donít know about the deviceís own port.

I should try plugging in my afedri to the RPi and see if those two can communicate....

SDR - Software Defined Radio / RPi Ethernet question
« on: June 21, 2020, 0338 UTC »
So if Iím connecting a device with a static IP directly to my RPi via Ethernet, any speculation why it wouldnít be detected?  I know the cable is good, I know the Ethernet is good (I can ssh into the RPi from my mac), and I know the device is fine (i can ping it from my macs Ethernet port).  Thereís something about the damn RPi configuration thatís just not meshing...I even checked that the device and the RPi have the same subnet mask.
Any ideas?

General Radio Discussion / Re: RPi based ham radio wall clock
« on: June 20, 2020, 1439 UTC »
I didnít notice this was from CSI. I know them from xephem, which is an awesome cross platform  astronomy program.

That said...I wish I could justify buying a real geochron.  Those things are just iconic.  They make a cheaper black box version that you plug into a monitor, but the mechanical version is just awesome.

Equipment / Re: RF circuit help....
« on: June 16, 2020, 1641 UTC »
My NanoVNA finally arrived.  As expected, the diplexer chops down on the 200-400Mhz sensitivity. The top scan is my DJ-130, the middle scan is the UHF (~800-900 MHz) yagi, and the bottom is the combined feed from the diplexer.  What's curious is that the amount of attenuation around 300 MHz doesn't appear too massive (within a log at least) yet i've lost a 380 MHz system.   Still playing around with it.....

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