Skip to main content

Via Soldersmoke: the Rockmite v3's SA612 Mixer has Gone End of Life

Cartoon-style infographic titled “Good-bye SA612 – A Mixer That Powered QRP for Decades.” The blue and yellow OctoToucan mascot waves goodbye while holding an SA612 chip next to a small RockMite radio that says “73!” in a speech bubble. The background is a bright yellow sunburst with red and blue panels showing the chip’s origins, specs, and discontinuation notice from NXP. A timeline along the bottom marks “Release,” “Proliferation,” and “Discontinuation,” and a red banner urges readers to plan for substitutes and follow Project TouCans for updates.
The humble SA612 mixer chip, long a cornerstone of QRP and RockMite transceiver designs, has officially gone end-of-life. Announced by Bill Meara on Soldersmoke, the news marks the close of an era in home-built HF radios. KO6BTY and I have relied on this little chip throughout Project TouCans, and while it’s never failed us in the field, its retirement feels like losing a trusted bandmate. 

Bill on Soldersmoke announced this news.

The mixer, the SA612, used in the Rockmite portion of Project TouCans has gone end of life. KO6BTY and I have never had one go out on us, but it's still a little surprising to hear that the chip won't be made anymore.

Here's Bill's full report.

One of Bill's first articles on the venerable mixer.

The Rockmite v3 manual.

The latest Rockmite ][++ Transceiver kit 


Close-up photo of a green RockMite circuit board showing an SA612A mixer chip surrounded by orange capacitors, a blue electrolytic capacitor, and a coax connection — a compact, hand-built QRP transceiver module.
A surface mount SA612 nestled into one of my green-board RockMites


Some of the latest audio from the RockMite inside Project TouCans


The SA612’s departure reminds us how quickly radio history turns its dials. Explore Bill’s reports on Soldersmoke, revisit NA5N’s early notes, and check out QRPme’s RockMite kits while they’re still available.
👉 Dive deeper: follow Project TouCans for ongoing experiments, QRP field activations, and new circuit explorations beyond the SA612.

The excellent ham radio blog: Soldersmoke

All the posts about Project TouCans

Comments

Post a Comment

Please leave your comments on this topic:

Popular posts from this blog

Cool Math Tricks: Deriving the Divergence, (Del or Nabla) into New (Cylindrical) Coordinate Systems

Now available as a Kindle ebook for 99 cents ! Get a spiffy ebook, and fund more physics The following is a pretty lengthy procedure, but converting the divergence, (nabla, del) operator between coordinate systems comes up pretty often. While there are tables for converting between common coordinate systems , there seem to be fewer explanations of the procedure for deriving the conversion, so here goes! What do we actually want? To convert the Cartesian nabla to the nabla for another coordinate system, say… cylindrical coordinates. What we’ll need: 1. The Cartesian Nabla: 2. A set of equations relating the Cartesian coordinates to cylindrical coordinates: 3. A set of equations relating the Cartesian basis vectors to the basis vectors of the new coordinate system: How to do it: Use the chain rule for differentiation to convert the derivatives with respect to the Cartesian variables to derivatives with respect to the cylindrical variables. The chain ...
11 comments
Read more

The Alcubierre Warp Drive Tophat Function and Open Science with Sage

I transferred yesterday's Mathematica file with the Alcubierre warp drive[2] line element and space curvature calculations to the  +Sage Mathematical Software System  today, (the files been  added to the public repository [3]).  If you haven't used Sage before, it's a Python based software package that's similar in functionality to Mathematica.  Oh, and it' free.  I also worked a little more on understanding the theory, but frankly, I made far more progress with the software than the theory.  What follows will be a little more of the Alcubierre theory, plus, a cool Sage interactive demo of one of the Alcubierre functions[1], as well as a bit about my first experience with using Sage. Theory The theory is fun, but it's moving slowly.  Here's the chalk board from this morning's discussion Alcubierre setup the derivation using something called the 3+1 formalism which means we consider space to be flat, (in this case), slices that are labelled ...
3 comments
Read more

The Valentine's Day Magnetic Monopole

There's an assymetry to the form of the two Maxwell's equations shown in picture 1.  While the divergence of the electric field is proportional to the electric charge density at a given point, the divergence of the magnetic field is equal to zero.  This is typically explained in the following way.  While we know that electrons, the fundamental electric charge carriers exist, evidence seems to indicate that magnetic monopoles, the particles that would carry magnetic 'charge', either don't exist, or, the energies required to create them are so high that they are exceedingly rare.  That doesn't stop us from looking for them though! Keeping with the theme of Fairbank[1] and his academic progeny over the semester break, today's post is about the discovery of a magnetic monopole candidate event by one of the Fairbank's graduate students, Blas Cabrera[2].  Cabrera was utilizing a loop type of magnetic monopole detector.  Its operation is in...
1 comment
Read more