Friday, January 31, 2014

New 4-port USB hub seems great with Linux so far!

HAH!  This is good for a laugh.

I used an LP-PAN for at least 3 years.  I've used HDSDR + Realtek 2832 Dongles now for about 1.5 years.  I would NEVER (EVER, EVER, EVER) go back to using a LP-PAN and sound card.  

The price of a high end sound card, plus the cost of the LP-PAN (including shipping on both items) plus the time and effort to get the sound card adjusted properly plus the limit of only being able to see at Max 192Khz of RF spectrum is prohibitive, and simply DOES NOT PERFORM as well as Larry thinks it does in the real world.

NAP3 and use with a soundcard is downright aggivating when trying to calibrate and maintain a proper input level from the soundcard driver to NAP3.

In comparison far an away will outperform the LP-PAN.  Not only that it's cost is less than the total cost of ownership of the LP-Pan setup.  Additionally it can display with a HIGH accuracy at up to 2.4Mhz at a time rather than 192Khz.   Oh and one more thing...if you are on 6m, and you experience with the LP-PAN swamping of the display during a strong Es opening and have to constantly dick the the sound card levels, try turning on the AGC in the Dongle Driver with HDSDR instead, and RELAX, it won't happen again.

Nice try Larry, but LP-PAN vs. Realtek dongles are apples and oranges.  And your remarks show how little you really have used the USB dongles to date.  Sorry, but sound cards are OUT OF DATE for IQ data.  They just are.  Nobody wants to be locked into 192Khz or less anymore. 

I'd love to see something better like IQ via Light!  And avoid the soundcard limits and noise, and loss, etc...

Tuesday, January 28, 2014

Flare Causes Brief HF Blackout

Observed a brief HF Radio Blackout caused by a Solar Flare today. (cool!)

gev_20140128_19002014/01/28 19:00:0019:46:0019:40:00M4.9S14E75 ( 1967 )

Monday, January 27, 2014

Solar Flares Showing Up?

Still looking for more detail, but it's interesting these broad spectrum spikes seem to be around times of flares when EM47qu (my location) was still likely to see/hear the sun.

I dunno the times are close, but not really right.  more research needs to be done to make sure I'm logging the times right, I'm pretty sure I am.  If so, they don't really seem to always line up.

There's definitely something causing wide band noise, or a sweep from time to time.  The 1/27 11:08 & 20:15 seem close, as does the 22:05 and 1/28 00:31-39 is on time also.  

However in the graph below there's something at 1/28 0240 that isn't in the NOAA tabular data below.  It may be something else, or perhaps it wasn't a solar flare, but some other galactic event?  

This graph has a tighter time scale

R820T MUF Observation

Friday, January 24, 2014

Click on the image above to see a larger version.

So I've been working on a Wide-Band RF Sensor using RTL (realtek TV dongles) for the past few days.  I'll post some more details on this, but Just wanted to get this image out.

This is two hours of RF Power data from 24Mhz to 1Ghz.  

During this collection, you can see the bright horizontal line.  This is when I removed the HF blocking filter, and the FM Broadcast Stop-Band Filter.  OBVIOUSLY these are required!  The dongles are massively impacted by strong signals.

I just wanted to share this...quickly.  the Y-axis is TIME bottom is most recent top is 2 hours ago.  The X-axis is frequency.