Micro908 News Blog
(October 15, 2010)
The REFL3 reflectometer project is proceeding well in beta trial and we may produce a daughtercard upgrade kit available for all Micro908 owners to buy and install if they wish.
(March 15, 2010)
It's been a while and just wanted to let you all know the Micro908 project is still alive and well here. Some exciting new steps are about to be happening, and here's a preview ...
MassCon Presentation & Use of Micro908
I wanted to point you over to a presentation that design partner N2CX and I did together at a conference this past weekend up in Massachusetts called MassCon ... http://www.midnightdesignsolutions.com/MidnightLoop/index.html
For the past year or so we’ve been working on a new STL (magnetic loop antenna) design and we found the Micro908 Antenna Analyzer to be of immense value during the development, field trial and documentation of things. You can see the use of the instrument about mid-way in the slide deck. No other instrument that would have worked to help us achieve the results we got!
Now that this major milestone has passed, I’m able to focus near exclusively back on the REFL2 project in order to finish off the accuracy improvement project. As a reminder, this daughtercard can be added to all existing Micro908s, if desired (it’s not mandatory), and it will be available at cost for all current Micro908 owners. It will be added to the kits for new Micro908s being ordered, with a corresponding price hike, which by definition will be more than just the cost of the parts.Displaying Raw Impedance Z
Further, it’s likely there will be an incremental step that is proving to improve performance without going the full “REFL2 path.” Stay tuned for this news, as I’m just about ready to unveil this improvement.
(BTW, if you are new to this Micro908 list, REFL2 is a small project add-on to improve accuracy of the Micro908 impedance and SWR readings. See http://www.amqrp.org/kits/micro908/REFL/refl2.html for more detail.)
Someone mentioned that it would be useful to optionally display raw impedance (i.e., in the form of scalar value Z) instead of complex impedance R +/- jX. We made some quick tests here and agree (a lot), so there will shortly be an updated software version containing this feature.
Amazing “HC908 VFO” Program also works in Micro908!
Last month I had a little time to work on a request of a friend to provide improved VFO software for the HC908 + DDS-60 card combination. We’ll I got carried away and developed some software using those common daughtercards that is really quite useful ... Multiple memory, frequency offset, and frequency scaling for controlling a SoftRock transceiver. You can see this project at http://midnightdesignsolutions.com/HC908VFO/index.html.Micro908 Overview Videos Posted on Website
But the best news about this HC908 VFO software is that it also runs on your Micro908 instruments! Since the Micro908 also uses the HC908 and the DDS-60 components, and the rotary encoder and LCD display, all you need to do is dial up the “Load New Software” function and load the hc908vfo_3a.s19 file from the website, and you too will be running the VFO program on your Micro908. Connect the RF output up to your transceiver and you’ll be off and running with a nice, stable and controllable Micro908 VFO. [Remember always to select Default Settings” after loading any new software into your Micro908].
Some time ago we created a videos that overviewed the Micro908 and it was placed on the Homebrewer Magazine CD set (see http://midnightdesignsolutions.com/index.html), but for some reason didn’t make it to the Micro908 website ... Duh! So they are there now. Check the top of the Micro908 page page for these links ( http://www.amqrp.org/kits/micro908/index.html). Hope you find it interesting and helpful in understanding the instrument.
Okay, that should suffice for a “coming out
party”! I’ve recently been completing a number of Micro908 Kits for guys
who got stalled, so more and more instruments are starting to appear again.
Let me know if you are having trouble finishing up your kit and we’ll
gladly provide some reasonably-priced assistance.
Meanwhile, hope to hear from those of you who are successfully using the Micro908 (like me on a regular basis), and stay tuned for some exciting things happening soon. We’re hoping to have things unveiled well before the Dayton Hamvention!
73, George N2APB
(May 19, 2008)
(January 25, 2008)
We have been working on a reflectometer upgrade daughtercard that will retrofit to all existing Micro908 instruments in the field in order to provide increased accuracy and functionality. This will be made available "at cost" to all existing Micro908 owners, as desired, and will be incorporated into the the main pc board for the next round of kitting done later this year. We expect to have this REFL2 daughtercard upgrade available at Dayton this spring.
(January 10, 2008)
Someone recently asked for a comparison
between the Palstar ZM-30 and the Micro908 ...
The Palstar ZM-30 (http://www.palstar.com/zm30.php) is a licensed, derivative design of the Micro908 that has a ruggedized case and different power control (timer-based on/off for main power and LCD backlight). But it does not have any of the modular/extensible features of the Micro908 (DSPx, nonvolatile memory, audio amp, kbd and paddle inputs). All in all it's a good instrument that received a pretty good independent review by ARRL labs in the April 2005 issue of QST (I think). We licensed it to Palstar and they have implemented a subset of the overall capabilities. Palstar didn't use the daughtercard hardware arrangement, but instead designed everything onto the motherboard. But other than the features corresponding to these missing hardware items, the software is functionally identical. (The ZM30 also has neat power-on circuit that allows auto-poweroff, as well as the built-in LCD backlight control and timeout capability.)
Advantages of the Palstar ZM-30:
- Sold as an assembled/tested unit
- Rugged aluminum case
- Auto power on/off control & built-in blacklight display
- Support of an established, professional company known for building solid instruments
Advantages of Micro908:
- Sold as a kit (if you built up an ATS-3B, you will certainly have no problem.)
- Modular construction (controller, DDS, DSP daughtercards)
- Hardware platform has additional components: DSP, audio amp, nonvolatile memory, paddle/kbd/aux/audio connectors.
- Additional software programs can be field-loaded to use the Micro908 as an Antenna Analyzer and DSP Audio Filter. (Other programs soon to be available (at Dayton) include Memory Keyer, Morse Keyboard, and a Digital Modem Controller.
- Hardware and software design is all open and under GPL license for anyone's use in creating new or custom versions of existing programs.
Both the ZM-30 and the Micro908 optionally connect to a PC for the use of utility programs, Link908 and Plot908, to plot and display SWR and Z, and provide remote control of the instruments. And the software for both instruments can be upgaded in the field over this serial connection to the PC, allowing for new software releases to be loaded up.
(November 2, 2007)
Here's some juicy updates on the major upgrade design projects that have been in motion this spring/summer for the Micro908.
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Page last updated: April 2011