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December 22, 2024. So how do you turn a Direct Conversion Receiver into a Transceiver?

Friends and colleagues, Bill, N2CQR and Dean, KK4DAS, developed a Direct Conversion Receiver project that was featured in "hackaday" and the subject of a local High School STEM type project.


Actress Terry Moore (now 96) Read about her in Wikipedia

If you have listened to or watched on You Tube the SolderSmoke Podcasts #254 and #255 then you know this has been the subject of a challenge to another podcast group and to the ham community in general. Dean, KK4DAS in January is sponsoring a 4-week Zoom Buildathon to construct the DCR.

W7ZOI Original DCR Circa 1968


The N2CQR/KK4DAS DCR designs builds upon the FOAM concept championed by Farhan, VU2ESE. FOAM is an acronym for the four parts of the DCR: Filter, Oscillator, Amplifier and Mixer. See if you can spot the FOAM pieces in the W7ZOI design? Because Bill and Dean know stuff, if you follow along, you will be able to do stuff.

But I opine that just building the DCR while it adds to your knowledge base and provides a deep sense of satisfaction of becoming an elite member of a small group who actually built a usable receiver -- it is still a receiver, a superb one at that. The real clout of such a project is taking the next step and making it into a CW transceiver.

So how do you take their DCR and make it into a CW transceiver? That is the $64K question. Now mind you the project is to build their design, not your design. The heart of their DCR is a homebrew PTO (you know LC Oscillator). Using only their design makes things a lot more complex and challenging than what may be done with an Arduino and Si5351 using CLK1. 

So how do you do that? If you are looking for a drum roll and/or a quick schematic on a back of an envelope from me -- there is none! 

The several sub-challenges include the Offset and the Change Over from Receive to Transmit. Along the way is RIT and Sidetone. These could all be done inside of an Arduino sketch -- but no Arduino would be used.

Just think your very own (not store bought or built from a kit) CW transceiver that will produce many FB contacts. BTW before adventuring out in the CW bands, learn how to send good CW. Regrettably many signals being sent today are pure crap with letters run together and terrible spacing!

Happy Holidays.

73's
Pete N6QW

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