Yet Another !&*%$! Noise Source

The past few days, I have noticed higher than usual noise levels, generally on the lower frequencies, and particularly on the longwave band, including the 285-325 kHz DGPS band, where I run nightly SDR recordings, to later process the data and decode and detect DX DGPS stations using my Amalgamated DGPS app.

Thinking back to what new electronics devices have been added to the house, two came to mind, a new cable modem, and a new ethernet switch. The switch is up here in the shack, so it seemed to be a likely candidate. The switch is a D-Link DES-1008E 8-Port 10/100 Unmanaged Desktop Switch. It uses a mini USB port for power, using either the included AC adapter, or power from a USB port. When I installed it, I decided to not use the AC adapter, but rather a USB port on my UPS, figuring it was better to not add yet another potentially noisy switching power supply to the mix.

The test was easy, I just unplugged the power to the switch. Sure enough, the noise vanished. Great, the switch is a RFI generator. Or is it? As another test, I plugged it into a port on a USB hub. No noise. Hmm… so it seems that the noise is indeed from the USB port on the UPS. I did not notice any increase in the noise floor when I got the UPS a few months ago, but It’s something I should look into again, just to be sure. The UPS is a CyberPower CP1350PFCLCD.

Here’s a waterfall from the SDR, showing the DGPS band, 280-330 kHz. You can see where I changed the power to the switch from the UPS USB port to the USB hub, the bottom part of the waterfall is when the switch was still powered by the UPS (click to enlarge it):

I still have a noise source just above 305 kHz to hunt down.

Update

I decided to see what I could do to improve things, and reduce the noise floor.

Here is the baseline, after no longer powering the switch from the UPS:

First, I relocated the AFE822 away from the computer and rats nest of assorted cables behind it, powered from an HTC USB charger:

The squiggly noise around 305 kHz vanished!

I then switched to an Apple USB charger / power supply, as their products tend to be a bit better made:

Another improvement, the overall noise floor is a bit less now.

But can we do better? I then switched to an older USB hub for power to the AFE822, that I thought might be better filtered:

I then changed to a linear supply plugged directly into the AFE822. I don’t notice any obvious improvement? Maybe it even looks like a little more noise? Difficult to tell. You can see a DGPS station popped up on 304 kHz while I was switching things around, between the last two tests, it was likely Mequon, WI.

Winter 2016-2017 Snowfall

On Parr’s Ridge in northern Carroll County, MD.

Contest
Guess The Amount of Snow At Casa De Smolinski

Seasonal Snowfall Contest Entries

  2.2	Ok_now_3-2-1_DANK-HANK
  3.2	Pamsm
  4.4	I love Kate
  5.0	hee hee
  7.5	Questsnow
 12.5	83worldtraveler
 19.7	Groveton
 23.6	Snowbi-wan Kenobi
 24.1	A CAMDEN WALKER
 25.7	wadejg
 26.2	Kate commenting
 27.0	taylort2
 29.4	Autumn_Forge
 29.7	heroine.chic
 31.6	cameraman
 31.7	Rex Block
 33.3	bob919
 35.1	Xtrain21
 36.5	walter-in-fallschurch
 38.4  	pct_atc
 43.2	NorthArlington101
 45.6	Terpiecat
 50.2	eric654
 53.4	AndrewinStafford
 54.5	chrisofthebeagles
 57.3	BigCountry
 57.9	slamslam
 79.0	surewhynot
120.0	The Adorable Miniature Snowplows
201.7	Days Of Weather Past

Saturday November 19, 2016:
Sleet. Changed to light snow before ending.

Sunday November 20, 2016:
Snow flurries.

November Total: 0.0″

Sunday December 11, 2016:
0.1″ Snow.

Saturday December 17, 2016:
0.5″ Snow and sleet, then 0.2″ freezing rain.

December Total: 0.6″

Friday January 6, 2017:
2.8″ Snow.

Saturday January 7, 2017:
Light snow, no accumulation.

Tuesday January 10, 2017:
Light snow, 0.1″ accumulation.

Wednesday January 11, 2017:
0.07″ of freezing rain, accumulation on the ground and road surfaces only, due to above freezing air temperatures.

Saturday January 14, 2017:
Sleet, light snow, freezing rain.

Friday January 27, 2017:
Snow flurries.

Saturday January 28, 2017:
Snow flurries.

Sunday January 29, 2017:
Snow flurries.

Monday January 30, 2017:
0.5″ of snow from a quick squall.

January Total: 3.4″

Thursday February 9, 2017:
3.0″ of snow after rain.

Wednesday February 15, 2017:
Snow flurries and graupel.

February Total: 3.0″

Friday March 3, 2017:
Light snow, 0.1″ accumulation.

Friday March 10, 2017:
Light snow, 2.8″ accumulation.

Tuesday March 4, 2017:
11.0″ of heavy but not wet snow.

A view of one of the ponds. Sadly there are frog eggs under all that snow:

I hope the Lilac makes it:

Saturday March 18 – Sunday March 19, 2017:
2.0″ of snow.

March Total: 15.9″

2016-2017 Season To Date Total: 22.9″

Summary of Halloween 2016 Shortwave Pirate Radio Activity in North America

After a slow start, Halloween 2016 pirate radio activity over the extended weekend picked up, especially Sunday and Monday evening. At one point on Monday there were at least four stations on at the same time.

I counted 68 broadcasts that were logged, and have summarized them below in chronological order, each linked to the corresponding logging thread on the HFUnderground.com shortwave pirate radio message forum. Hopefully I haven’t made any typos.

A big thanks to all the stations that gave us listeners lots of programs to listen to!

Here’s the list:

Friday, October 28, 2016:
RELAY STATION 5150 on 5150 AM at 1359 UTC.
An UNID on 6925.5 AM at 1813 UTC.
Radio AV was testing on 6925 AM at 2102 UTC.
Old Time Radio on 6770 AM at 2245 UTC.
Moonlight Radio on 6929 LSB at 2351 UTC.

Saturday, October 29, 2016 (including Friday night):
An UNID on 6925 USB at 0015 UTC.
Bat Country Radio on 6955 USB at 0022 UTC
Another UNID on 6935 USB at 0055 UTC.
PeeWee Radio on 6955 USB at 0128 UTC.
WAHR (Automated Halloween Radio) on 6955 USB at 0300 UTC.
Yet another UNID on 6955 USB at 0348 UTC.
Amphetamine Radio on 6925 USB at 1514 UTC.
An UNID on 6925 USB and then AM at 1900 UTC.
Another UNID on 6930 AM at 2139 UTC.
Radio Illuminati on 6150 AM at 2206 UTC.
Pumpkin Patch Radio on 6930 USB at 2252 UTC.
Old Time Radio on 6770 AM at 2225 UTC.
Radio Free Furry on 6945 USB at 2352 UTC.

Sunday, October 30, 2016 (including Saturday night):
Moonlight Radio on 6930 USB at 0002 UTC.
Pee Wee Radio on 6955 USB at 0133 UTC.
An UNID on 6950 AM at 0204 UTC.
Another UNID on 6925 USB at 0215 UTC.
Another UNID on 6925.1 AM at 0218 UTC.
Yet another UNID on 6925 AM then USB then LSB at 0342 UTC.
Radio Halloween on 6925 AM at 1156 UTC.
One more UNID on 6930 AM at 1248 UTC.
Radio Halloween on 6925.4 AM at 1526 UTC.
An UNID on 6963 LSB at 1542 UTC.
Radio AV on 6925.7 AM at 1616 UTC.
An UNID on 6930 USB at 1635 UTC.
RELAY STATION 5150 on 5150 AM at 1901 UTC.
Radio Merlin via RELAY STATION 5150 on 5150 AM at 2014 UTC.
Witch City Radio 6925 AM at 2039 UTC.
Radio Merlin International relay on 6925 AM at 2128 UTC.
Radio Fusion Radio on 6930 USB at 2143 UTC.
Captain Morgan Shortwave on 6924 AM at 2155 UTC.
An UNID on 6950 AM at 2157 UTC.
Old Time Radio on 6770 AM at 2205 UTC.
The Yodeler on 6930 USB at 2228 UTC.
RELAY STATION 5150 on 5150 AM at 2234 UTC.
The Yodeler on 6925 USB at 2236 UTC.
Radio Fusion Radio on 6925 USB at 2242 UTC.
Rave On Radio on 6935 USB at 2300 UTC.
The Yodeler on 6930 USB at 2312 UTC.

Monday, October 31, 2016 (including Sunday night):
RELAY STATION 5150 on 5150 AM (received in Brazil) at 0018 UTC.
An UNID on 6924.7 USB at 0013 UTC.
NRUI (Amelia Earhart callsign) on 6925 CW at 0204 UTC.
WAHR (Automated Halloween Radio) on 6925 USB at 0216 UTC.
An UNID on 6925 USB at 0235 UTC.
An UNID on 6925 USB at 1524 UTC.
Amphetamine Radio on 6925 USB at 1753 UTC.
Radio AV on 6925 AM at 1916 UTC.
Amphetamine Radio on 6923 USB at 2053 UTC.
Old Time Radio on 6770 AM at 2205 UTC.
Doctor Detroit on 6935 AM at 2237 UTC.
Moonlight Radio on 6930 USB at 2254 UTC.
An UNID on 6925 USB at 2304 UTC.
Witch City Radio on 6873.4 AM at 2309 UTC.
An UNID on 6940 LSB at 2338 UTC.

Tuesday, November 1, 2016 (including Monday/Halloween night):
An UNID on 6925 USB at 0008 UTC.
Wolverine Radio on 6935 USB at 0013 UTC.
Pumpkin Patch Radio on 6925 USB at 0034 UTC.
XFM on 6960 AM at 0042 UTC.
An UNID on 6950 USB at 0046 UTC.
Canadian Radio After Dark on 6950 USB at 0048 UTC.
Undercover Radio on 6975 USB at 0058 UTC.
Renegade Radio on 6925 at USB.
WJD on 6930 USB at 0130 UTC.

Only one Europirate was logged on this side of the pond: Enterprise Radio was on 6950 AM at 2200 UTC on the 31st They sent an SSTV image, which I was able to receive with poor quality:

RainBrandy from Germany had better reception, as you might imagine: