segunda-feira, 21 de fevereiro de 2011

Using CW Skimmer and PowerSDR-IF with K3

This last weekend was the ARRL DX CW, an old favorite for me. I couldn't travel to my station, so I decided to make just a few contacts from home and test some new ideas.

My goal was to have CW-Skimmer decoding the band I was working, generating spots to win-test.

For that, I connected my K3 to the LP-Pan panadapter and an E-MU 0202 USB Soundcard. The K3 was also connected to a Microham Microkeyer II.

This is the basic setup:

The interface to the transceiver is through the MKII. The Microham USB Router software allows for two CAT virtual COM ports, and I routed one directly to the logging software (Win-test) and the other to LP-Bridge, a piece of software by Larry, N8LP, that further splits the CAT chain. LP-Bridge provides CAT virtual COM ports for the PowerSDR-IF (panoramic display), and for the CW Skimmer.

The CW Skimmer has a built in telnet server, which is accessed by the Win-test DX-Telnet application (part of the Win-test suite) as a local host. After logging-in the spots from Skimmer start flowing into Win-test and are plotted in the bandmap.

The important thing is to keep track of all configurations used. There are several virtual COM ports involved, and the settings must be identical at both sides of the communication link. I took printscreens of all configuration windows, for future reference.

When I first started using PowerSDR and LP-Pan, a few months ago, I had some problems with spur images along the spectrum display. That was solved by replacing the cables between the LP-PAN and the soundcard with some better quality ones (Radio Shack part #42-2433).

As I said, this was not a major contest effort, I just made a bunch of QSOs to check the setup. I still don't know how it will perform during a major effort, but the results look promising. From my little operating, I noticed I almost never checked the Pan display at PowerSDR-IF. Maybe it can be dropped to save computer resources. By the way, my not-so-new Sony Vaio FE (dual core, 1.66MHz) did handle all the simultaneous tasks quite well.

Of course the use of Skimmer makes this a Single Operator - Assisted entry.

Some links:


And a nice video in Youtube (not mine)

I'll post some photos and videos in the future.

73 de PY1KN

Um comentário:

  1. I´ve received two interesting comments.

    First, Larry, N8LP suggested setting the sampling rate down to 96kHz (even better at 48 kHz), to get better resolution and lower noise floor. Since most activity during CW contests is quite concentrated, this should be worth a try.

    The other tip comes from Felipe, PY1NB. The Skimmer spots can be routed to the Reverse Beacon Network just by running a small software in the background

    Thank you guys!