Ed W4YWA is far too modest -- he has built a very FB homewbrew transmitter.  Congratulations Ed.  I think your original plan to use a Web SDR receiver will work, if you and the other station are just willing to pause for an additional second or two to let the internet catch up with the real world.  Also, you might find some Web SDRs that have less latency than other.  You could used a little SW receiver or a simple buzzer for your sidetone ( I think sidetone is your most pressing latency concern.)   My suggestion is to try to get a few contacts using the We ..read more

Click for a better view Esteemed QRP Hero Chuck Adams AA7FO saw me struggling with the T/R switch on my hamfest-found MXM SupeRX/TX transceiver. Chuck kindly sent me a modification of the circuit that allowed for automatic T/R.  I see it also envisioned the use of a VFO.  We are not sure if this version of the MXM transceiver ever made it to market, but it certainly would -- in any case -- be of interest to homebrewers.   Chuck wrote:  Attached is a schematic I drew for Bruce almost 30 years ago with a program that I wrote.  This is for the Simple Transceiver ..read more

  FB Chuck, very cool.  Please send us more reports on this rig.   Chuck has been on the blog many times, with many projects:  https://soldersmoke.blogspot.com/search?q=KE5HPY 73  Bill  ------------- Bill/Pete:   Thought you would appreciate a recent project inspired by the fabulous EMRFD.  This started as a test bed W7ZOI universal tx to evaluate my stock of RF BJTs and employ some FT-243s in the shack.  That was interesting by itself but the 16-32 dBm output (choice of device really matters!) did not reach the intended targets using my 40m ..read more

I hope readers have picked up on the discussion of the Islander DSB rig out of Cuba. We had a bit of a breakthrough on this recently. I've been writing about it on the blog:  https://soldersmoke.blogspot.com/2024/04/re-building-islander-dsbcw-rig-in-cuba.html  One thing I think is especially interesting:  The Cubans were using parts taken out of old Soviet TV sets.  One of the tubes used in the VFO section of the Islander was known among the Cuban hams as "the little spider."  Arnie Coro CO2KK explains why:  "VFO is made with ONE of the 6 "little spi ..read more

  Today's aparatus (above).  Chamber is larger and I left the bottom sealed.  It sits directly atop a chunk of dry ice.  The spongeat the top is soaked in alcohol.  This is a one minute clip.  It does seem a bit like watching paint dry, but you will see many atomic particles moving through the cloud. If you look to the right side of the screen you will see that the cloud has started to rain alcohol.  I will put additional clips on the Patreon site.  Harry Cliff's wonderful book mentions the origins of the cloud chamber.  Click for a better vi ..read more

The VFO Board The "motherboard" for an Islander Islander boards recently obtained in Cuba by CO7WT Pavel CO7WT is making great progress in re-building an Islander DSB rig, the same kind of rig that got him started in ham radio, and that was so popular in Cuba years ago.  Here are some background blog posts on this rig:  https://soldersmoke.blogspot.com/search?q=Islander  In essence, the Islander was the earlier tube DSB/CW rig; the Jaguey was a later, solid-state DSB/CW rig.  When they get this Islander going, hams outside Cuba should definitely try to work this re ..read more

  My Cloud Chamber It was time to take a break from building SSB transceivers.  I wanted to build something completely different.  I went with something that I've wanted to build since I was a kid. Sometime in the late 1960s, I read about a Wilson Cloud Chamber in the book "The Amateur Scientist" by C.L. Stong  (my mom got the book for me, at great sacrifice).   You have to make a little cloud in a chamber.  When an atomic particle flies through (as they do!) it will leave a little trace in the cloud.  Cool.  Literally cool: This is a dry ice ..read more

Run, don't walk, to this video series by RF MAN.   He is truly, THE MAN!  Pete N6QW found this series, passed it to Dean KK4DAS, who alerted me.  Thanks guys.  This is a six part video series on how to design an HF 50 watt RF linear amplifier using our beloved IRF-510 MOSFET.  Each video is about 30 minutes long.  The author (who is this genius?) makes great use of LTSpice.  I have been using this software for years, but still I learned a lot by watching these videos:  AC Analysis.  How to change the values of the things you are measuring ..read more

This is for CW fans, or for those wishing to improve their CW skills.  You can now listen to the entire H.G. Wells book in CW, thanks to Chuck Adams, AA7FO.  This seems very timely becasue my son and I are watching the NETFLIX version of "The Three Body Problem" by Cixin Liu.   This deals with an entirely different war of the worlds.   Check out Chuck's CW version of the book.  Thanks Chuck!  https://www.aa7fo.com/war-of-the-worlds.html ..read more

  https://spectrum.ieee.org/apollo-era-antenna-voyager-2 From the IEEE article:  The dish’s manufacturer took great pains to ensure that its surface had no bumps or rough spots. The smoother the dish surface, the better it is at focusing incident waves onto the signal detector so there’s a higher signal-to-noise ratio. DSS-43 boasts a pointing accuracy of 0.005 degrees (18 arc seconds)—which is important for ensuring that it is pointed directly at the receiver on a distant spacecraft. Voyager 2 broadcasts using a 23-watt radio. But by the time the signals traverse the multibillio ..read more