{"id":22446,"date":"2016-11-30T11:33:41","date_gmt":"2016-11-30T15:33:41","guid":{"rendered":"http:\/\/swling.com\/blog\/?p=22446"},"modified":"2018-01-20T10:34:16","modified_gmt":"2018-01-20T14:34:16","slug":"a-preliminary-review-of-the-pk-loop-c-loop-hdsw6-18","status":"publish","type":"post","link":"https:\/\/swling.com\/blog\/2016\/11\/a-preliminary-review-of-the-pk-loop-c-loop-hdsw6-18\/","title":{"rendered":"A preliminary review of the PK Loop C-LOOP-HDSW6-18"},"content":{"rendered":"
\"eecraft-kx3-pk-loop\"<\/a>

The Elecraft KX3 and the PK Loop C-LOOP-HDSW6-18<\/p><\/div>\n

Over the past year, a number of SWLing Post<\/em> readers have asked me to review the PK Loop portable magnetic loop antenna produced by\u00a0Paul Karlstrand in Australia<\/a>.<\/p>\n

I finally caved in and purchased one.<\/p>\n

I ordered the shortwave version of the loop, the\u00a0 C-LOOP-HDSW6-18<\/a> in early November and received it about one week later.<\/p>\n

\"sony-sw100-pk-loop\"<\/a>

The Sony SW100 tuned to WBCQ.<\/p><\/div>\n

I was first introduced to this antenna by SWLing Post<\/em> contributor, Mark Fahey<\/a>, who brought it to the SWL Fest and our 2015\u00a0PARI DXpedition<\/a>.<\/p>\n

Mark has taken his PK Loops (both the shortwave and mediumwave models) on his numerous travels around the world. He finds that they’re relatively effective portable antennas in RFI-dense environments like hotels and guest houses. They’re better at mitigating RFI than, say, portable wire antennas or telescopic whips.<\/p>\n

Mark hooks up his portable SDR to the PK Loop and makes spectrum recordings\u00a0(wideband recordings)–from, say, his hotel room in Kuala Lumpur–then takes the recording back home to listen and tune at his leisure via his laptop or tablet PC. \u00a0While I’ve certainly made spectrum recordings while travelling in the past, the appeal of such a portable loop antenna is what finally caused me to pull the trigger.<\/p>\n

Overview<\/h2>\n

\"pk-loop\"<\/a><\/p>\n

The PK Loop is a small loop antenna–measuring about 12″ in diameter. It’s encased in UV-stabilized PVC conduit and the matching box also seems to be made of PVC. It feels very durable and can, no doubt, even survive the wildest of luggage handling.<\/p>\n

The PK Loop has an attached battery 9V battery holder, but can actually be powered by any\u00a09-18 volt DC supply. Current consumption is less than 15 mA. On the matching box, you’ll find a tuning knob, a BNC connector, DC power in port and a HI\/LOW gain switch. My loop shipped with a\u00a02 meter BNC-BNC Cable, 3.5mm adapter,\u00a0and DC Power lead to open ends.<\/p>\n

Operation<\/h2>\n

Operating the loop is very simple:<\/p>\n

    \n
  1. Power the antenna with a 9V battery or other DC source<\/li>\n
  2. Chose either the high or low gain setting<\/li>\n
  3. Place it on a stable surface (height from the ground is not a critical\u00a0issue, but you should avoid placing it next to noisy electronics or mobile phones)<\/li>\n
  4. Connect the PK Loop to your receiver’s antenna jack with the supplied cable<\/li>\n
  5. Turn on your receiver to the desired meter band, then adjust the loop’s tuning knob until you hear the signal level peak<\/li>\n
  6. Start listening, keeping in mind that as you tune around the band you may need to adjust the loop’s tuning knob for maximum gain<\/li>\n<\/ol>\n

    Loop antennas, in general, are fairly narrow-band and–unlike a Wellbrook<\/a> or Pixel Loop<\/a>–manual adjustments need to be made with the tuning knob to match the PK Loop as you scan across bands.<\/p>\n

    Still, I see why Mark favors the PK Loop for spectrum recordings: the bandwidth is wide enough that if I tune the loop to the middle of the 31 meter band, for example, it does a fine job covering the entire band.<\/p>\n

    On the air<\/h2>\n

    \"pk-loop-kx2-sw100\"<\/a><\/p>\n

    My free time has been very limited since receiving the PK Loop earlier this month, but over Thanksgiving holiday, I took it to my family’s home that has relatively high RFI levels.<\/p>\n

    The following are a couple of videos I made with my Moto X smartphone. I’ll be the first to admit that these are not the best videos–I had no tripod and the Moto’s microphone leaves much to be desired–but I think you’ll still get the idea of how well the PK Loop works.<\/p>\n

    With the Sony SW100<\/h3>\n