WA7HRG's Mighty Mite

From New Zealand - Roadkill Routers

Hi Andrew,

 

Now that is what I call "cost effective". It works so why not!

 

Good show.

 

73's

Pete

 

Sent: Tuesday, December 23, 2014 7:15 PM

To: Pete Juliano

Subject: Re: Thanks for the heads up on the Si5351

 

Thanks for the heads up regarding the SMA connectors and cables.  I will definitely do that.  Will probably use my first Si5351 as a network connected signal generator and get another Si5351 module to put "on the air".

 

FYI - rather than using Arduino (or some other microcontroller) I have been using recycled ADSL routers for my Si5351 and MEPT beacons.  DLink DSL-502T specifically.  These were the standard broadband router down here in ZL about 5 years ago but are now essentially free on the local auction site because everyone wants WIFI.  They can be flashed with OpenWRT (a Linux derivative).  They have enough GPIO pins that with a bit of configuration can easily control the Si5351 and other I2C devices. 

 

Bill talks about "road kill computers".... these are "road kill routers" but at $1 each you can't really go wrong. 

 

73

Andrew ZL1WJQ

 

Samana Shack

Just like in "How's DX?"

VE7BPO's QRP POPS IS BACK!

We were all understandably concerned when Todd VE7BPO announced this Fall that he was taking down his beloved QRP POPS web site.    I'm pleased to report that Todd has transitioned from Web Site to blog.   The spirit of QRP POPS lives on here: 

http://qrp-popcorn.blogspot.com/

There are also links on this blog to all the great stuff that was on Todd's site: 

http://qrp-popcorn.blogspot.com/p/blog-page_9.html

Three cheers for Todd!  Hip-hip...

Our book: "SolderSmoke -- Global Adventures in Wireless Electronics" http://soldersmoke.com/book.htm Our coffee mugs, T-Shirts, bumper stickers: http://www.cafepress.com/SolderSmoke Our Book Store: http://astore.amazon.com/contracross-20

Now in Santo Domingo

I wrapped up my Samana HI9 operation yesterday morning.  I found a very friendly Spanish-language round table - they were all willing to try to pull my QRP DSB sigs out of the noise.  Within a few minutes I worked KI4PZE, CO8OT,WA4RME,and CO8KB.   So that made a total of 18 solid contacts with 3 more that might not qualify as full-fledged QSOs.
We have moved on to very urban Santo Domingo -  no room for antennas here!

Our book: "SolderSmoke -- Global Adventures in Wireless Electronics" http://soldersmoke.com/book.htm Our coffee mugs, T-Shirts, bumper stickers: http://www.cafepress.com/SolderSmoke Our Book Store: http://astore.amazon.com/contracross-20

A Very Simple and Stable VFO

From the November 1964  issue of 73 Magazine, by way of a compendium book sent to me from New York City by Dave W2DAB, comes words of wisdom about how to make a simple, super-stable VFO. Lots of great ideas in this article.  My favorite was running the thing off D cell batteries and leaving it on all the time!  The article was written by Roger Taylor, K9ALD. 

Here is the article: 

http://archive.org/stream/73-magazine-1964-11/11_November_1964#page/n11/mode/1up

Thanks to Dave, Roger, Wayne Green and the Internet Archive. 

Our book: "SolderSmoke -- Global Adventures in Wireless Electronics" http://soldersmoke.com/book.htm Our coffee mugs, T-Shirts, bumper stickers: http://www.cafepress.com/SolderSmoke Our Book Store: http://astore.amazon.com/contracross-20

Pete Tries Baluns on the DBM

A couple of weeks ago I ran a post about an old 73 Magazine article that extolled the virtues of putting baluns at the RF input and IF output of diode ring mixers.   Dedicated experimenter that he is, Pete Juliano gave it a try: 

Hi Bill,

I did the modification and used 20 bifilar turns of #26 on a FT-50-43 core for each transformer.

The most important observation is that I did not see any degradation of performance and in fact I think has helped an overloading situation I was seeing on some extremely strong signals.

The photo is of a DBM that is behind a bilateral stage that on Rx is the RF amplifier and on Tx is the Tx pre-driver. I do have another single transistor RF amp ahead of this. In normal operation the next stage would be the Band Pass Filter.

The back end is an IF amplifier, AGC, Product Detector, balanced modulator and mic amp stage all on a board that came out of a Hallicrafters FPM-300 SSB/CW transceiver. There is a you tube video of this prototype project.

73’s

Pete N6QW 

Thanks Pete! 

Our book: "SolderSmoke -- Global Adventures in Wireless Electronics" http://soldersmoke.com/book.htm Our coffee mugs, T-Shirts, bumper stickers: http://www.cafepress.com/SolderSmoke Our Book Store: http://astore.amazon.com/contracross-20