Monday, September 8, 2014

Minima - Wayne's Build

Sunday I had a chance to work with Jeff - KO7M via Skype for a few hours. He has the loan of Wayne's (NB6M) Minima Transceiver for a few weeks while Wayne is on vacation - Thanks Wayne.

A large part of the discussion was about "How to Use Git and GitHub" for software development.

Wayne's Mimima
Afterwards, we decided to try to update Wayne's Minima to my latest Alternate Tuning Method transceiver control code. Wayne had previously downloaded and was using a much older copy of my code. The older copy did NOT have many of the NEW and current features and functions. Our goal was to exercise these new features on Wayne's hardware.

When we first downloaded my NEW Revision, Wayne's Minima went NUTS, with a loud Buzzing sound on all frequencies.

We reinstalled the old software and the Buzz went away.

Something that I had done over the last few weeks has made my software almost useless. With a little work, and via the process of elimination (removing sections of code), Jeff was able to track down the offending routine.

I had inappropriately moved two of the PTT Pin Initialization Statements to within the main TX/RX Idle Loop. This pin is also used to control the TX/RX relay. Rapid re-initialization of the PTT pin was producing hash that the receiver was picking up. Removing the two nu-necessary and redundant statements solved the problem. Initialization of the PTT pin is now done between Receive and Transmit and then when switched back.

The GitHub copy has now been updated.

While we had Wayne's Minima NOW working so well with the new updated code, I wanted to exercise each of the new functions. Wayne does not yet have a "seventh" push button installed, and therefore we had to use a jumper wire as a switch to access some of the functions. For the full list of new functions that I have added to Farhan's original Minima code, see Link. Everything worked better than expected - I am a Happy Camper.

One of my main interest was to see how well the CW ID and MACRO's worked, and how well the QRSS Beacon worked. They actually worked much better than expected!!

The Non-Volatile Save and Load of User Memories worked as expected. Dial Calibration for both USB and LSB was an easy task.

Over the next few weeks, Jeff will be introducing some new hardware support and functionality for the Minima. He has plans for multiple Si570's (VFO and BFO), other I2C Displays and more. See his blog at:

Contributing to the Minima Hardware and Software has been a very rewarding and interesting project, . . . Thanks, Farhan.

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  1. Eldon -

    Instead of using multiple Si570's, would it be possible to use a single Si5351? The 5351A has 3 outputs and provides a different frequency on each of those outputs, meaning that a single chip could provide both the VFO and BFO signal. On top of that, the Si5351A is much cheaper than the 570 - $3.35 from Digi-Key in single quantities.

    Jason NT7S used an Si5351 to good effect in his "Simple SSB" rig. It would seem to be a very cost-effective solution.



  2. Dave,

    Yes, the Si5351 is much cheaper, but it has a much higher phase noise specification. But, I think it would work, in fact I have already build a VFO Module with the chip. I have not tested it yet.


  3. I should have checked the specs before commenting. I should have known that a chip that is $10 cheaper and has 3 independently-programmable outputs would not have gone unnoticed by the Minima development crowd!

    Really appreciate your blog Eldon. Lots of good info and inspiration here.