Tag Archives: pid

CD101 PID Controller stop mode issue

The CD101 is an inexpensive (under $40) PID controller sold by Sure Electronics. Aside from the incomplete documentation that is shipped with the unit, I’m pretty happy with this controller. I’m planning to use it to replace the failed PID controller that controls my soldering hotplate.

I am having one small issue with the CD101 – stop mode doesn’t seem to do anything. By that I mean it doesn’t disable the outputs or seem to affect the controller in any way. Based on my interpretation of the user manual, the outputs and alarms should be disabled in stop mode. This is mostly an annoyance in my application – if I want to disable the hotplate I’ll just turn it off. However, I can imagine that the lack of a standby mode might cause problems in some applications.

I contacted Sure Electronics about the problem, and they requested a video. I figured I might as well post it here, since I went through the trouble of making it and everything. 🙂

By the way, since it can be hard to find information on this controller (eg. how to change from Fahrenheit to Celsius display), I have been slowly putting together a wiki page for the CD101.

PS: The video was shot with my new Canon PowerShot S95, which seems to take great footage, except that there is no autofocus or zoom control while shooting. (?!)

Changes to the MightyOhm Wiki


I’ve been making some changes and additions to the MightyOhm Wiki over the past few days.

To complement the awesome list of surplus electronics shops, I started creating wiki pages for the various projects I have previously documented on the blog.

Last night I added a list of cheap PID controllers to the wiki page for my DIY PID-controlled Soldering Hotplate.  (Backstory: the PID controller on my hotplate quit working this week and I’ve been shopping for a replacement!)

I have also  been adding more information to the PCB resources page, including where to order cheap solder paste stencils and resources for making test fixtures.

More to come…

Celebrating one year of hacks and projects at mightyohm.com!

Wow!  I can’t believe it’s been a year!

Based on the date of my first post, last Wednesday marked the one year anniversary of my blog.

While I pour a toast, here are a few highlights of the past year:

PID Controlled Solder Paste Fridge

PID Controller closeup

The first project I documented on the site, my solder paste fridge was the end result of a weekend effort to turn an old beer chest into a PID-controlled Peltier cooler for storing tubes of solder paste. A year later, the cooler has a permanent home under my workbench and is still going strong, keeping its contents at a chilly 36 degrees F. Besides solder paste, I keep my POR-15 rust proofing epoxy paint and a few tubes of superglue in the fridge (they never dry out!).

Space Invaders!  Making RGB video with the PIC

I needed an excuse to learn assembly language programming on the PIC, and this project fit the bill perfectly.  Instead of slogging through yet another PIC tutorial I decided to “just do it” and the video above shows the result.  One of my favorite projects of last year, I have plans to build more of these and make some electronic artwork for the lab.

Bluetooth Handset Hack


One aging bluetooth headset plus one obsolete telephone handset equals one retro-fabulous hack that I still use today.  The best part: Look for this one in Make: volume 20!

DIY PID-Controlled Soldering Hotplate

PID Controlled Hotplate

I’m a big fan of the hotplate (aka reflow skillet) method of surface mount soldering.  Over the course of a few months I designed, machined, and assembled this PID-controlled soldering hotplate to help build the first few prototypes of my AVR HV Rescue Shield kit.  Hacking around in the garage is always fun, but creating a new tool is one of the most rewarding things I have can think of.

Here’s a video of the hotplate in action, reflowing the step-up converter on the Rescue Shield:

The AVR HV Rescue Shield

AVR HV Rescue Shield

What started as a simple hack to save a crippled AVR microcontroller eventually became a kit that I’ve sold to AVR enthusiasts around the world.  The AVR HV Rescue Shield includes a cool custom PCB, integrated 5V-12V step-up power supply, and is completely open source.   I only made one batch of these, and when they’re gone, they’re gone, so head over to the AVR HV Rescue Shield product page to order one today!

Wifi Radio Project

Finished Wifi Radio

Certainly the most famous project on the site, my Wifi Radio project has inspired many readers to start playing with cheap wireless routers and embedded Linux.  If you haven’t seen it before, the finished project sounds something like this:

I brought the Wifi Radio to the Maker Faire in San Mateo in May.  Everyone loved it, including some of the Make: staff, which got me a blue ribbon for the project.  Awesome!


Well, that’s it for year one…  If I missed one of your favorite posts from the past year, leave a comment!  If you’re new to the blog, happy reading, you have some catching up to do.  🙂

Here’s to another fantastic year of hacks, projects, kits, tools, and resources at mightyohm.com!

Keith’s Hotplate and PID Controller Teardown Pics

Keith of Keith’s Electronics Blog made a PID-Controlled Soldering Hotplate based on the one I fabricated earlier this year.  He’s already using it to build the stepper controller PCB for the MakerBot CupCake CNC!

He also posted a bunch of teardown photos (like the one shown below) of the CD101 PID Controller from Sure Electronics.  I suspect the CD101 is a cheap knockoff of an RKC PID controller since I can’t find the part number on RKC’s website, even though the front panel clearly says RKC on it.  I guess at $40 you can’t ask too many questions, the price is right…

Copycat PID-Controlled Solder Hotplate « Keith’s Electronics Blog.