Euro Zone: SolderSmoke Kindle-book Now Available

SolderSmoke -- Global Adventures in Wireless Electronics is now available on the Amazon.de (German) web site. Payment in Euros.
https://www.amazon.de/dp/B004V9FIVW

WONDERMARK! (Comics with the Knack)

As part of our occasional series on Knack-related comic strips, today we present Wondermark. This link will take you to the first page: http://wondermark.com/tink1/ From there, look for the little "NEXT" hand on the right of the comic. There are eight. All of them are gems. Also, be sure to check out the author's bio:
http://wondermark.com/about/

WSPR -- THE MOVIE!

VK2TPM made some nice videos of the Weak Signal Propagation Reporting System (WSPR) maps over time. Its kind of fun to watch the propagation shift from trans-Atlantic to trans-Pacific.

More: http://www.youtube.com/user/vk2tpm#p/u/4/U1sBGZzNv8s

T/R Success with WSPR

Thanks to everyone who sent in advice on my WSPR t/r troubles. I now have it all sorted out. In the image above you can see the cable from the serial port that carries the RTS T/R signal from the computer. It goes to a switching transistor that controls a relay that in turn switches the three relays that actually do T/R for the rig. One question: On the Linux computer the RTS signal seems to switch between +5 and -5 volts, but on the Windows machine it was +10 and -10. Why?
I'm really pleased to have the computer interface working. It is kind of neat to bring together the complex technology of the computer and the simple technology of a DSB/Direct Conversion rig.

Five Planets Visible in the Morning

The good folks over at spaceweather.com have once again alerted us to an important astronomical event: During May, early risers will be treated to a conjunction of Mars, Jupiter, Venus, and Mercury. (The fifth visible planet would be the one you are standing on!) The Moon is thrown in as a bonus. The photo above was taken by Liz Gleeson on Magnetic Island (Australia) -- what a great location!

More T/Rouble

I get the RTS signal when using a Windows PC, but when I try to switch over to a Linux computer, I don't get the T/R signal from pin 7. Is there some code or setting in Linux that I need to change to make this happen?

Working on T/R circuit for HB WSPR rig --need help!

I'm finally working on the PTT T/R circuit for my homebrew DSB /Direct conversion 30 meter transceiver. I hope to use the simple one transistor circuit from W3PM's FB HB WSPR rig.

But I need info on the PTT signal that will come from the computer serial port. Which pins on the 9 pin serial port connector? What kind of signal comes out? Is it 5 volts on transmit? What settings should I use in WSPR? RTS? Any other setting changes needed?

I hope to be transmitting AND receiving soon.