PSK31 Skimmer

Several years ago, May of 2013 in fact, I set out to create a "skimmer" for PSK31. A skimmer is a computer program that listens to all of the conversations it can hear and decodes all the data. After messing with it for a while, and not having much luck, I set it aside. Until a couple of weeks ago, that is. Ed Manuel N5EM gave me some of his old QEX's, and one of them had an article on PSK31 written by the guy who invented it. He talked about how his PSk31 detector worked, and gave me some ideas on how to improve what I'd written.

What I've Been Up To Lately

It's been a while since I've put anything here, but I've been busy the whole time.

I received a Peaberry SDR V2.0 kit as a gift, and I've been assembling it. I've gotten to the point where the entire receiver is built and works, and I'm working on the transmitter. I'm building the 20, 30, 40, and 60 meter version of it, if anyone cares. At some point, I'll have to find a nice Linux SDR application I can use it with. Up to now, I've just be using the recommended Windows application because it's recommended. I want to control the uncertainties in any project I do.

It's a Keyer!

The keyer, as I tested it.  No case, just arduino-y goodness.

Okay, I wired up the I2C interface to the LCD, connected the potentiometer for the speed control, and connected jacks for the key and the key out. Along the way, I found that I had labelled the I2C lines wrong, swapping the data and clock lines.

And, yesterday I created a keying cable to go between the keyer and the FT-102, and the radio keyed! So, I need to put it in a box.

The July 31, 2014 Arduino Memory Keyer Update

I survived ApolloCon just fine, and I'm more energetic than I can remember being, so I have started to work on projects again. I have too many projects, but I still want my memory keyer to be finished, so I'm working on that.

A while back, I finished the board layout for the correct transistor pinouts, and I sent it off to OSHPark to be turned into actual boards. I also ordered parts. Last week I even found out what was wrong with my soldering iron (it wasn't set up right at the factory) and I fixed it. So, I was all set.

Why I haven't been blogging

Just a quick note to let everyone know why I haven't been blogging. It's not because I don't have anything to say. I have been tempted to write about RM-11708, but I just don't have time. June is a horribly busy month for me, mostly because of my involvement in Apollocon, a science-fiction convention that has traditionally been held Field Day Weekend. I'll be back in July, and maybe even before then, but don't hold your breath. You'll turn blue.


The Future of DXpeditions

I got into a bit of a twitter exchange yesterday with some people. It started because Rich Holoch KY6R made his own blog post with the title "The Future of DXpeditions?" and my response "Expensive hobby + expensive trips = lots of old people on DxPeditions. Nobody else can afford it." got several retweets and a favorite or two, and a couple of responses. I have trouble fitting what I think about this into 140 characters, so I'll post it here.

How to Make an SDR CW Receiver

I've been working on an SDR (Software Defined Radio) receiver that I can control via computer so I can use my TV receiver dongle to work linear transponder satellites. It hasn't work or, rather, has kind of worked strangely so last night I took it apart, metaphorically, and experimented with locally-generated signals so I could try to figure out what was going on. Having identified the errors, corrected those errors, and tested the correction, I can now explain how to make one of those things that works. The receiver part, anyway.

Adventures in Satellite SDR

While I'm waiting for new boards to come in for the Arduino-based memory keyer and while I'm waiting for NC4L to get my money order so he can ship my FT-102 back, I'm working on getting back on the satellites. I've decided to try my hand at the linear-transponder satellites. I've watched guys like Andy (W5ACM) operate linear satellites with nothing more than an FT-847 and some well-practiced skills, but I don't have any FT-847 equivalent, and the all-mode radio that I do have is computer-controllable so I can run computer-controlled.


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