Due to the ongoing supply-chain issues many of the parts needed to build the original CTR2 system as published in the Sept/Oct 2021 and Jan/Feb 2022 issues of QEX magazine are out of stock with long lead times.

With this in mind, I’ve made the difficult decision to discontinue producing the original CTR2 system instead of redesigning it to use currently available parts.

This decision does not affect CTR2-Mini, which still available and in active development.

As part of this change, I’m refocusing this blog on CTR2-Mini. I’ve moved the CTR2 menu to the Support menu on the main page so all of the information on building and supporting CTR2 is still available.

I will maintain the current stock of parts and will provide technical support for the CTR2 systems in the field, I just won’t be building any more systems.


I intentionally designed CTR2-Mini with a minimum part count using readily available components. It’s much easier to build and much cheaper than CTR2 was. It also offers features that the original CTR2 product couldn’t such as SO2R operation with the new CTR2-Mini SO2R Controller. More information on CTR2-Mini can be found here.

As a side note, QST magazine has accepted a construction article on CTR2-Mini and plans on publishing it in the September 2022 issue.


I enjoy the creative process of dream, design, program, and build and hope you find inspiration in the things that I do. If you have questions about anything I’m doing please contact me. You can also find my email on my QRZ.com page.

73, Lynn, KU7Q