Retro 75

Ben (N2BEN) and Joe (9 years old and 7 years old respectively) helped me work on the "Retro 75" project today for a while.










We have all of the capacitors on the board. We are going to take a break to run some errands and pick up some groceries. With a bit of luck maybe we can out in another hour or so tonight after dinner.

73 de NG0R

Whispering

Since I am not using the radios in my shack this morning I decided to turn on the K2 and let the Ubuntu machine that runs the shack decode WSPR signals on 30m.

I planning to spend a little bit of time over at the work bench this morning so I thought I could help out other folks by letting my system do some decoding and posting while I solder in the other room.

When I turned it on around 10am central either the band was extremely active or there was some band enhancement... it was wall-to-wall signals.  It is kind of funny, I can also see some QRSS signals at the bottom edge of the screen. Look at the snake like signal. /\/\/\/\/\/\/\/\/

I don't think that I have ever seen the sub band this active.  I probably should design a dedicated receiver that can just listen and send the audio to a machine (or VM) to do decoding.  When I am working during the week my radios sit inactive most of the time.

73 de NG0R... headed over to the work bench.

Retro 75

I decided to crack open the box for the Retro 75 kit tonight.

I sorted the parts in my standard box for small projects.


I then inspected the board and placed it into the Panavise on the workbench.


I did not start the installation tonight. I will probably start it this weekend. Tomorrow night is supposed to be rainy so that might be a good time to visit the workbench for an hour or two.

Things to acquire:
--Microphone
--Case/Enclosure (Likely will be a Hammond box.)

73 de NG0R

End of March 2010 notes

Random Notes about March 2010

• March 2010 had no significant snow in our area. That is a first in over a hundred years of local record keeping.
• Birds started nesting and actively hanging out around the house on Monday 3/15.
• We planted our tomato and pepper seeds (indoors) on Monday 3/15. (8 weeks till planting.)
  
• Our ground has largely been frost free since mid March. (We live on a hill so we are generally about 2 weeks ahead of the surrounding communities where it is flat.)
  
• Jacob and I spent Thursday night 3/25 at the Science Museum of Minnesota along with about 200 other 5th graders from Dassel-Cokato Middle School. (Think of the movie a Night at the Museum.) Yes, we CAMPED out in the museum in sleeping bags overnight.
  
• I heard the frogs talking on Monday 3/29. There is a medium sized marsh across the corn field from us... they are loud enough for us to hear once they become active for the season.
  
• We brought the camper home from Storage Wednesday 3/31.
• We removed the snow blower and three point blade from the tractor on Wednesday 3/31.
• I saw my first two mosquitoes of the season today Wednesday 3/31.
  

Triple PN2222 Class C Amp

I did not have a lot of bench time tonight... but I did not really need much given the low parts count for this project.

I look forward to hooking this up to the signal generator and power meter. It will be interesting to see how much drive it takes to turn these on in Class C.

73 de NG0R

Triple PN2222 Class C Amp

Tonight I got back to the work bench to work on one of my projects.


The image below is an old schematic and the three 50 ohm resistors were replaced with a single resistor so that the circuit presents a 50 ohm impedance to the signal generator.

I had to hunt for the schematic and the image below so that I could remember what I was thinking when I came up with this experiment.


This is a Class C amp using three parallel PN2222 transistors. The idea was based upon some schematics that I saw doing something similar with FETs. If it can be done with a FET it should be possible using something like a PN2222.

I printed up the board about a month ago but had not gotten around to finishing the project. So tonight while participating in the "Builders Net" on EchoLink (using my Netbook+Qtel at the work bench) I drilled the board using my dremel-press. I recently bought a bunch of BNC right angle PCB connectors. My original design assumed that I would connect the board to the BNC via a short lead or some mini coax. I decided to mod the PCB tonight to accept the new connectors right on the board.

When time permits one evening this week I would like to stuff the parts. Once that is completed I can connect the signal generator and power meter. There are three things that I would like to measure:

• Power consumption
• Input drive level limits/requirements
• Output power level
  

73 de NG0R

The Retro 75 has arrived!

My package from Dave Benson arrived this afternoon.


As much as I might like to build it tonight I think that I will wait a couple of days. Maybe I can get Jacob (N0AEA) to help work on this one with me at the workbench.

SDR-Shell

Here is an interesting look SDR tool for Linux. (SDR = Software Defined Radio)

http://ewpereira.info/sdr-shell/

I am looking for forward to at some point focusing on my SDR project and getting them built and operational. Ideally my Softrock will drive a 28mhz to 144mhz transverter which will drive 902mhz, 1296mhz, and 10ghz transverters.

There are not too many people doing this on Linux so it should be an interesting voyage.

73 de NG0R

Svxlink, Qtel, and EchoLink

EchoLink will work on Linux using WINE. It works but sometimes can be a little flaky. I am not a huge EchoLink user but I do want it work properly as I talk with some other folks that are interested in building radio and electronics gear.

There is an Open Source project call SvxLink that offers a client (QTEL) and a server component.
http://sourceforge.net/projects/svxlink/

The challenge that I have is that they only have pre-built packages for Fedora based distros that can use RPMs. I use Ubuntu which is based upon Debian which uses DEBs for installation packages. In theory this should not be an issue because they list the sources files and give you instructions for how to compile it for your platform.

http://sourceforge.net/apps/trac/svxlink/wiki/InstallSrcUbuntu
sudo apt-get update
sudo apt-get install g++ libsigc++-1.2-dev libgsm1-dev libpopt-dev tcl-dev libgcrypt11-dev libspeex-dev make alsa-utils
sudo apt-get install libqt3-mt-dev
wget  http://downloads.sourceforge.net/svxlink/svxlink-090426.tar.gz
tar xvzf svxlink-090426.tar.gz
cd svxlink-090426
make
sudo make install

In theory that is pretty simple... until you throw an error!  I am running Ubuntu 9.10 32bit and it appears that some important things might have changed since the instructions were written for 8.04 and 8.10.

--- Compiling AsyncSerialDevice.cpp...
AsyncSerialDevice.cpp: In member function ‘void
Async::SerialDevice::onIncomingData(Async::FdWatch*)’:
AsyncSerialDevice.cpp:299: error: ‘perror’ was not declared in this scope
make[3]: *** [AsyncSerialDevice.o] Error 1
make[2]: *** [all] Error 2
make[1]: *** [all] Error 2
make: *** [all] Error 2

It appears that a couple of folks are talking about tweaking this install and then creating a deb.  So what does a person do until that is available?  --Of course... you Google to see if you can find someone that already has made a deb for testing. I found an old build at: http://hb9hli.radioamateur.ch/public/ubuntu/svxlink/ Install the couple of debs that are listed and you should be in business. I was able to get this to run on an ASUS EEE 900HA with Ubuntu 9.10 in about 2 minutes.

The images show the QTEL client.


This version appears to be pretty old. It runs and appears to be pretty stable based the initial testing that I did with the EchoTest conference room. At some point I would like to get the newer client running so that I can get visual feedback on my audio levels.

This tool is not as full featured as the standard EchoLink client but it appears that all of the important pieces are there and it appears to be more stable than running EchoLink under WINE.

Ok... enough time playing computer for this morning. I need to run some errands. Once I get those done I hope to make it back to the work bench and work on some radio and electrical projects. I will probably test QTEL out tonight on the QRP conference around 8:15pm central time.

73 de NG0R

PS... Here is another location to try: http://www.chrisronk.net/ham/linux.htm
Chris has converted the RPMs to Debs with Alien. It was on my to-do list but it looks like he might have it working. I am going to try it on another laptop that is headed to workbench but is not critical around here.

Wind Train CP 9704 - Cutting Snow

Here is a delayed photo....

A Canadian Pacific train hauling wind farm components across central Minnesota. The photo was captured on 2/15/2010 a few miles west of Watkins, MN as the train is headed eastbound.