July 2015 Verifications

KELY Ely NV 1230 (tnx OJS)
KBZZ Reno NV 1270 (tnx Ole Forr)
KSGG Reno NV 1230
WILM Wilmington DE 1450 (via FB, last remaining US state confirmed; USA #900 excl. Hawaii, I was asked to submit a liner for their morning show)
Radio Carve, Montevideo 850 (tnx Horacio Nigro)
WJDA Quincy MA 1300 (via Google Hangout)
WBRK Pittsfield MA 1340
WPRO Providence RI 630
WPRV Providence RI 790

RFSpace CloudIQ samples 1500 kHz!

It didn't take long for RFSpace to do a firmware update to allow sampling of 1500 useable kHz with 16 bits. For the MW DX-er, this is indeed good news!

RFSpace CloudIQ: Sensitivity & I/Q Bandwidth

Sensitivity may not be an important issue for many DX-ers, especially if they live in a high signal level environment. To me, sensitivity is an important issue, and I always make sure to measure the sensitivity levels of my receivers.

Up until now, all SDRs have been somewhat inferior to the best conventional receivers. Such as the NRD-525 (-114 dBm) and the R-390A (-116 dBm).

My SDRs of various guises have weighed in at -93 to - 106 dBm, with the exception of the Winradio G33DDC which made the -110 dBm mark with the preamp engaged.

RFSpace promised the CloudIQ to be considerably more sensitive that the SDR-IQ, and indeed we have a new SDR winner of the weak signals prize. The sensitivity was a uniform -111 dBm from 500 kHz (my lowest measurement) to 20 MHz (my highest). The measurements were done in AM mode, 6 kHz bandwidth, 400 Hz tone into 30 % modulation.

Pieter Ibelings at RFSpace informed me that they had spent a lot of time on the matching of the ADC. Evidently their efforts paid off.

The 19 meter band on the CloudIQ

The I/Q sample rate maxes out at 1 MHz, 24 bits. Now, this is a little less than desired for recording the MW band for later analysis, as 160 kHz on the 540-1700 kHz range is missing; 173 kHz for the European/Asian 531-1704 kHz range. The older NetSDR also has a 1 MHz, 24-bit limit, but in addition it has two 16-bit bandwidths, 1.3 and 1.6 MHz. 

I sincerely hope that the CloudIQ will be given a similar option.

CloudIQ I/Q bandwidth (NetSDR bandwidth for comparison in green frame)

New Toy

A new radio is ready for testing. I was lucky enough to be among those who got the first batch of 100 or so receivers, and I will look forward to testing it the coming weekend. For anyone not familiar with the CloudIQ, here's the story:

More as it happens.

Recent Verifications

(Well, not so recent... since March actually)

WGVA Geneva NY 1240
WAEB Allentown PA 790
WMAL Washington DC 630
WMLM St. Louis MI 1520
WMEL Cocoa Beach FL 1300
WDAE Tampa Bay FL 620
WRTA Altoona PA 1240
WTVL Waterville ME 1490 (tnx OJS!)
KNEU Roosevelt UT 1250

An Alternative Way To Power Your Perseus

While the stock, switching 5VDC power supply for the Perseus is among the quieter ones, it doesn't perform adequately in an extremely low noise environment. Linear 5V power supplies aren't abundant, and they often come at a price.

Unlike the RF Space SDR-IQ, the Perseus draws too much current to be powered from most  PC's USB 2.0 outputs which are usually limited to 500 mA. However, with the advent of the USB 3.0 standard, this has changed. The Perseus typically draws 700-750 mA, while a standard USB 3.0 output will deliver around 900 mA - more than enough for a Perseus.

This needs a proper power cord with a USB connector in one end and a 2.5 mm connector in the other. It is perfectly feasible to build your own, and there are several DIY instructions on the net. I wanted to avoid potential problems related to poor soldering skills though, and then I found this on Ebay:

It's a custom made power cable for the Perseus. It sells from the USA for a nickel short of $20, + shipping. I've bought three of these, and they work perfectly. The seller claims they are "roughly 6 feet", which is roughly true as the last cable I bought measured in at 5.75 ft/175 cm.

A cable like this is an absolute must have if you want to do an outdoor DX session. You can power your Perseus from a laptop or a battery pack, and use the laptop to run the Perseus from a different USB port.

All my three Perseus in Kongsfjord are now powered from PCs and they seem to cope well.

This particular item will pop up if you do a "perseus sdr" Ebay search.

Admittedly there are literally hundreds of Chinese-made USB-to-2.1 mm cables on Ebay, with prices as low as 0.99 USD/EUR including shipping. I haven't spotted any 2.5 mm cables though.

Whatever you do, always check the polarity of the connector before you power up the Perseus. Mistakes do happen.

February 2015 Verifications

CBT Grand Falls/Windsor NL 540

CBNA St. Anthony NL 600

WATR Waterbury CT 1320

CJLO Montreal QC 1690

HJIP BBN 1590 AM, Bogotá 1590

WRNI Providence RI 1290

KXLO Lewistown MT 1230

CHRF Montreal QC 980 (Canada #215)

KBMW Breckenridge MN 1450

WYSL Avon NY 1040

WOND Pleasantville NJ 1400

WAMG Dedham MA 890

CHML Hamilton ON 900

WERC Birmingham AL 960 (North America #1100)

KCLK Asotin WA 1430

WKNY Kingston NY 1490

WSLB Ogdensburg NY 1400 (#50 on 1400)

WATN Watertown NY 1240

Radio Capital, Lima Peru 1470 (thanks Arvid Husdal)

WTWD Plant City FL 910 (thanks OJS)

January 2015 Verifications

KRKC King City CA 1490

KXPA Bellevue WA 1540

WKOX Everett MA 1430

WXKS Newton MA 1200

WMMV Cocoa FL 1350

WNTN Newton MA 1550

WCMC Wildwood NJ 1230 (tnx Jarmo Patala)

WMID Atlantic City NJ 1340

WRKO Boston MA 680

KRZR Fresno CA 1400 (tnx OJS)

WVEI Worcester MA 1440

WTAG Worcester MA 580

CFCB Corner Brook NL 570

KTIP Porterville CA 1450 (tnx OJS)

KCMY Carson City NV 1300

WAXY Miami FL 790

WCTC New Brunswick NJ 1450

WPIE Trumansburg NY 1160

WNBP Newburyport MA 1450 (USA #900)

WROC Rochester NY 950

KMYC Marysville CA 1410

KOBO Yuba City CA 1450

WMNN Pompano Beach FL 1470

WKBK Keene NH 1290

WDMC Melbourne FL 920

December 2014 Verifications

KICD Spencer IA 1240

KBIZ Ottumwa IA 1240

KINO Winslow AZ 1230

CKMK Mackenzie BC 1240

November 2014 Verifications

WQSC Charleston SC 1340 (facebook) – “graveyard” station # 200.

KCIK Kihei HI 740 (tnx OJS)

KLER Orofino ID 1300 (pdf)

KBAM Longview WA 1270 (tnx ABU)

KUOM Tumwater WA 1340

KGIW Alamosa CO 1450

KGGS Garden City KS 1340

WBUC Buckhannon WV 1460

WNDE Elkins WV 1240

WMCR Oneida NY 1600

KUIK Hillsboro OR 1360

KPIO Loveland CO 1570

KEWE Kahului HI 1240 (Hawaii # 30, on test mode at low power)