Monday, April 24, 2017

New features for BITX40v3

The latest v1.07 Raduino software can be downloaded from https://github.com/amunters/bitx40 , and the user instructions are found at https://github.com/amunters/bitx40/blob/master/operating%20instructions  .
This new version adds upper sideband so that now the BITX40 can be used for digital modes on 40m. Note that you must use the si5351 v2.0.1 library with the Arduino IDE for it to compile. You must also add a "Function" pushbutton to access all of the new features, which are listed as:

Added functionality via the Function Button
  • Use a pushbutton to momentarily ground pin A3 (orange wire). Do NOT install an external pull-up resistor!
  • dual VFO A/B capability (RIT is not yet working though)
  • LSB/USB mode selection
  • Settings menu for calibration, tuning range, VFO drive level
  • All settings are stored in EEPROM and read during startup
Here is a picture of my BITX40 receiving JT65 on 7076 KHz. The USB bandwidth is a little narrow to receive the entire JT65 band, but by tuning up 1 or 2 KHz, it can be covered. I haven't gotten the transmit working yet.  73, AL - VE3RRD


Here is a picture of the BITX40 receiving WSPR on 7038.6 KHz USB. I am using the software WSJT-X for both modes.


Sunday, April 16, 2017

Minimum BITX40v3 Hacks

The two mods that everyone should be adding as soon as they get their BITX40v3 are the Q13 protection diodes at K1 and the 2nd harmonic reduction mod (100 pF NPo 100V capacitor across L7 in the output filter). 

The Q13 protection mod is extremely important as there have been hams who have blown Q13 within hours (or even minutes) of getting their new BITX40v3 working and hooked up to an antenna. The cause is because they transmitted on a nearby antenna with their 100W or higher station rig while the BITX40 was receiving on its antenna.

The symptom of a damaged Q13 is that receive still works fine but there is no transmit. Note that although Q13 is a driver for the transmitter circuit, its base is connected to the antenna during receive.

Q13 can be replaced by a 2N3904 transistor (there is an SMD version if desired). 73, AL VE3RRD





The 2nd harmonic is a little too high for North American standards. Add a 100 pF 100V NP0 capacitor across L7 in the output filter. This will reduce the 2nd harmonic by about 20 dB. If you are planning on increasing the output power above the normal 5 to 7W, then you should use a 200V capacitor.



Tuesday, February 21, 2017

BITX40

Here are a couple of pictures of my BITX40. I was able to get the DDS upgrade kit from HFsigs.com, so I dropped the idea of making my own from an Arduino Nano and AD9850 DDS. The transceiver is mounted in a 1/4 inch plastic and aluminum angle stock frame. The microphone is a small plastic box with PTT switch glued in hole on side and the mic element hole on the end (so it can be used either left or right handed). I found that the speaker I have mounted to the right of the circuit board didn't produce the best audio experience, so I added a socket to the back panel to plug in an external speaker which has very good audio.  73, AL - VE3RRD



Sunday, January 8, 2017

BITX40 Fun

Some of us have just purchased the BITX40 SSB 40m transceiver from HFsigs.com . This is a kind of revolutionary radio, not just because you get a working 40m SSB transceiver for $59 US, but also because it permits those hams who are afraid of building a kit transceiver from a bag of parts a chance to "roll their own". What you get for your money is an assembled and tested transceiver board, with all the various parts needed to mount it in a box of your choosing and get it on the air.


The BITX40 that I purchased did not include the digital display and digital VFO as it is now sold (mine was $49 US). The versions sold now cover the entire 40m band and let the buyer add or modify to his liking.

 

Because mine didn't include the Arduino controlled DDS/display board, I am adding an AD9850 DDS and Arduino Nano clone which will use the software from AD7C. In the above two pictures, you can see the temporary course and fine tune pots sticking out the side. These will be removed once the digital VFO is working. They even included an electret microphone element which I have put into a small plastic box with a PTT button.
My first BITX40 to BITX40 QSO was with Tom VE3THR, the radios sounded very good except that the analog tuning had a lot of drift. The new version solves the drifting problem with the digital VFO.
Power output is about 7W peak or more when connected to a 13.8V power supply, but the design allows you to up the voltage to the PA to as much as 25V which will give you about 20W output (of course you will need to use a larger heat sink). Check BITX Hacks for ideas on modifying your BITX40. The Yahoo BITX20 Group covering this transceiver has moved to "groups.io" at https://groups.io/g/BITX20 . There is also a Facebook group called "Bitx40v3 40m radio kit".

The answers to many questions that prospective or new owners of the BITX40 may have can be found on the "Unofficial BITX40 FAQ" page at  http://miscdotgeek.com/unofficial-bitx40-faq/  


Tuesday, December 27, 2016

Barrie Amateur Radio Club webpage

Visit the Barrie Amateur Radio Club temporary webpage at http://themuskokan.com/ for information about our ham radio club and its activities.

The club's permanent webpage at http://www.barriearc.com is currently under re-construction.

Monday, September 19, 2016

Ham Radio at the Beeton Fall Fair

Some members of the club set up a ham radio display at the Beeton Fall Fair for two days on September 17 and 18. Above is Jack VE3RDQ and Brant VE3UME. Also there were Al VE3RRD (taking the picture), and Jay VE3JXT.

Above, I have my KX3 set up on a small table with paddles and straight key. To the right is my home made 15m through 40m magnetic loop antenna which I didn't try transmitting on, but also seemed to pick up quite a few signals. In front of the magloop is my 80 AHr battery with TGE N8XJK 25A boost-regulator to provide 13.8 VDC to the radios (see http://stores.tgelectronics.org/ for more on this product).

The silver pole on the left is a 16 foot painter pole with an Arrow 2m/70cm J-pole antenna on top. The black one is a 33 foot MFJ-1910 telescoping fiberglass mast which I used to support a 31 foot end-fed antenna with 9:1 unun (Balun Designs 9130sw). This antenna performed very well even though I was using the van as the counterpoise.

In the foreground is the painter pole inserted into a surplus tripod staked to the ground. Behind it you can see the "foot" made from a 2 foot long piece of 2x6 with a pipe flange bolted to it and a 6 inch piece of threaded 1-1/4 inch pipe. I have one of the fiberglass 4 foot military tent poles (available from Mapleleaf Communications or from Princess Auto) slipped over the pipe (I had to add a piece of rubber hose over the iron pipe to tighten it up inside the tent pole). The 33 foot mast is fastened to the tent pole with duct tape, and with the van wheel sitting on the "foot", the whole vertical antenna was very stable. The 9:1 unun ended up being about 2 feet off the ground. Since I couldn't have counterpoise wires because of the people walking around, I used my booster cables to fasten the ground lug to the body of the van.
This antenna worked better than I expected, with strong signals being heard through the day on 15, 17, 20, 30 and 40m. Although we only worked a few stations, we did have a good time at the Beeton Fair, and I had a chance to try out my 31 foot endfed configuration. I also have a 52 foot wire that can be used when tall trees are available as the support; this longer wire also works on 80m.

Friday, September 2, 2016

Last night the WAX Group had real raspberry pie to go with their Raspberry Pi.


It was finger licking good. The freshly baked raspberry pie from Barrie Hill Farms was supplied by John VE3FDZ.


As Mike VE3MKX said: "the WAX Group - always going where no radio builders group has gone before..... raspberry pie..... then ice cream!"

Friday, August 19, 2016

WAX Group members
We had a good turn-out of members last night (18 August). Clockwise starting from the left-front:
Tom VE3THR, Eric VA3EEB, Greg VE3YGG, Ian VA3QT, Ryan VA3RRE, Andy VA3TNE, Mike VE3MKX, John VE3FDZ (in blue T-shirt), Al VE3RRD, Jack VE3RDQ, James N6NRD, and Bill VA3OL (in the red shirt). Taking the picture is Ken VE3KDG. James N6NRD still has to write the exam to obtain a Canadian call.

Wednesday, August 3, 2016


NorCalQRP lives again! A number of years ago, this group sold several kits and published a newsletter called "QRPp". The original website is still found at http://www.norcalqrp.org/  and you can download the groups old "QRPp" newsletters from http://www.ncqrpp.org/ . As you can see, this interesting newsletter existed from 1993 until it ceased publication in 2003.
Recently, the NorCal club has begun holding monthly meetings again (in San Jose, California), and Doug Hendricks KI6DS has taken on publishing "QRPp, Journal of the NorCal QRP Club". The latest issue for August 2016 (Volume 12 Issue 1), and future issues can be downloaded from the "FILES" section of the NorCalQRP Yahoo Group found at  https://groups.yahoo.com/neo/groups/norcalqrp/info . Just join the group to have access to upcoming issues of this great newsletter.


Sunday, July 17, 2016

I just used Ed K3HTK's auto fldigi install script to install fldigi on my Raspberry Pi 3. The script works very well, I have my Pi connected to my KX3 - you can find the script at:  http://indyham.com/news/fldigi-install-script-for-raspberry-pi-latest-version-3-23-12/ . FLDIGI is a free program that offers many digital modes including PSK31, RTTY, Hell, MT63, Olivia and even CW. Versions are available for Windows, Apple OS X and Linux. You can download fldigi from :  https://sourceforge.net/projects/fldigi/files/fldigi/


73, AL - VE3RRD