General News

VA6DX FPV Flight over Red Deer Picnic

From Barry Bergstrom VA6DX

Hey Bob. Here’s a quick video of the FPV flight from last weekend. You’re welcome to embed it on the CAARC site if you like; just but a note on to watch it in 720p or 1080p for a better effect. 

Thanks Barry great video





The Royal Canadian Mounted Police amateur radio Group in Ottawa will be operating a Special Event Station VE3RCMPduring the Field Day contest weekend, June 28-29, 2014.  We plan also to activate the call sign during the RAC Canada Day Contest July 1st.

The Special Event Amateur Station will be commemorating the 75th anniversary of the first RCMP owned and operated radio-to-patrol-car dispatch system that was commissioned in the fall of 1939 using the call sign VY8T and thus initiated a continuing Radio Support-Service within Force.   VE3RCMP during Field Day will be operated by current and retired members of what is currently known as the RCMP National Radio Services Directorate, Ottawa.

The last time VE3RCMP was obtained for field day operations was in 1989 during the the 50th anniversary.  We hope the 4 letter suffix will not cause too much confusion to other FD contest station operators.

Special QSL cards are being prepared to confirm contacts with VE3RCMP.

Norm Rashleigh, VE3LC

RAC Bulletin

June 16th 2014

Red Deer Hamfest – Central Alberta Amateur Radio Club

Hams from many parts of Alberta met last weekend at a hamfest in Red Deer hosted by the Central Alberta Amateur Radio Club (CAARC).

Groups such as the Southern Alberta Amateur Radio Club (SARA) and Alberta RAC/ARES took advantage of the opportunity to meet and conduct their business. RAC President Geoff Bawden, VE4BAW and Director Mitch Mitchell, VE6OH, (Alberta and Northwest Territories and Nunavut) were proud to make a presentation of RAC shirts to CAARC Club President Bob King VE6BLD and Garry Jacobs, VE6CIA Alberta Section Manager.

Mr. Bawden made a presentation on the recent history of RAC and outlined our future. The return of RAC to financial solvency and its accomplishments since 2010 were discussed with members.

RAC would like to acknowledge and thank CAARC for the grant of $600 to help cover Mr. Bawden’s travel expenses.

Mr. Bawden will be visiting other groups in Alberta before he returns home to Winnipeg, Manitoba.

Web link with photo:


Rac Comms

Radio airwaves get buzzed from pot

Subject: Radio airwaves get buzzed from pot
BlankRan across this in USA Today. Thanks BOB K6YBV!!

Radio airwaves get buzzed from pot By Trevor Hughes,

A few years ago, retired electrical engineer Tom Thompson noticed it was
getting harder and harder to hear his friends across the country talking to
him on their ham radio sets. So Thompson built a portable antenna system to
track down whatever was interfering with his radio transmission.

The culprit? Marijuana grow operations, whose powerful grow lights can emit
interference blocking radio broadcasts on the ham and AM spectrums.

The first grower he encountered wasn’t pleased to know Thompson, now 73,
could tell what was going on. “He said, ‘What are you going to do, call the
cops?’ Thompson said. “And I said, ‘Well no, it’s a federal matter.

‘ With 22 states and the District of Columbia allowing medical marijuana,
and Colorado and Washington permitting recreational use, there’s been an
explosion in the number of people growing their own pot, much of it indoors.
With that growth has come increasing interference from the grow lights,
which suck down huge amounts of electricity to shine upon budding marijuana
plants. Growing pot indoors is usually more secure and gives the grower more
control over light, water and insects, which results in higher-quality
plants commanding a premium price.

The interference problems from one type of system have gotten so bad that
the amateur radio association, ARRL, filed a formal federal complaint on
behalf of the country’s 720,000 licensed ham operators. The problems are
worse in Colorado and California, said Sean Kutzko, an ARRL spokesman.

The interference is caused by what are known as “ballasts,” electronic
systems controlling the grow lights. Unless they’re properly shielded, the
ballasts can throw off a wide range of interference. “We’re seeing numerous
cases … and that’s causing us a problem,” Kutzko said. “We just want to
make sure the manufacturers are in compliance with FCC laws. The FCC has the
power to regulate anything that interferes with licensed radio
transmissions, such as ham sets, but also cellphones and AM radios.

Google Calendar

FOX Project Cube Sat

Reprinted from AMSAT NA
Phase 1 Fox satellites are 1-Unit CubeSats. They each include an analog FM repeater that will allow simple ground stations using an HT and an “arrow” type antenna to make contacts using the satellite. This was the mode made so popular by AO-51. The Phase 1 CubeSats also have the capability of operating in a high-speed digital mode for data communications. Two of our phase 1 Fox satellite projects have already been accepted into the NASA ELaNa program for free launches.

Preliminary Fox Keplerian Elements

We now have a launch for Fox-1 in 2014.  These Keplerian elements approximate the perigee, apogee, and inclination of the orbit.  They have been tested in several popular tracking programs, and will give a good feel for the availability and footprint to be expected.  Other details will depend on the launch site and deployment profile.

1 99999U 13001A   13115.03159480  .00000000  00000 0  00000 0 1    14
2 99999  64.0000 106.4735 0200000 270.0000 180.0000 14.81480000    10

With the IARU coordination received, the uplink frequency will be 435.180 MHz, and the downlink frequency will be 145.980 MHz.  For those using the SatPC32 tracking program, you can add the following line to the DOPPLER.SQF file:


We will update these as the launch approaches and more specific information becomes available.

Fox-1 Engineering Prototype.

Ham Radio on the International Space Station

The International Space Station Expedition 25 landed on Nov. 25, 2010.

Station commander Doug Wheelock gave a great tour and demonstration of the Ham Radio on board before he came home.

VE6YXR 444.550MHz linking system

Congratulation Jeff VA6JL who bought, borrowed, aquired and traded for all the equipment needed to put together 3 fully functional linked UHF repeaters and install them at three sites on a shoestring budget. The usual HAM way.

CROSSFIELD  ( NOT AT MONIES MUSHROOM )      448.750 – 5 MHZ   PL 107.2

SUNDANCE  ( NORTH PIGEON LAKE )                    448.750 – 5 MHZ    PL 100.0
HEATBERG   ( SOUTH OF ALIX  )                             449.875 – 5 MHZ   PL 107.2
these are all on line and linked full time to VE6YXR in Red Deer 444.550 + 5 mhz no tone
Hope to hear you on and give us some coverage reports going forward.

Ham radio TV show

Testing “generic” MOSFETS for RF PA use

Testing “generic” MOSFETS for RF PA use

Earl, 4Z4TJ / VA6TJ

Low cost plastic MOSFET transistors can be used to make effective low power HF PAs.  I have an amplifier I made with IRF510’s that effectively brings a Softrock transceiver output up to legal QRP (5 W out) with a 15 volt power supply.  With that experience in mind, I started looking for plastic MOSFETs that were actually designed as RF amplifiers, and not as components in a switching power supply.

A while ago I bought some supposed RF MOSFETS on eBay from a supplier in China.  I did not take sufficient care in checking out the history of the parts that are marked MS1307 from International Rectifier.  A bit of Googling around showed that IR never made a transistor designated MS1307.

I decided that the transistors needed to be tested under actual RF amplification conditions, and not just with a multi-meter.  Therefore I build up a simple test circuit,  based on a 40m CW xmtr by VA3IUL, where I could plug in a MOSFET and test it as a 40m amplifier.   The transistor socket was taken from the wiring harness of a discarded ATX computer power supply.  The source of Q2 (tied to the emitter of Q1) needs to be grounded to obtain output – this is where the CW key would be attached, or in my case I soldered in a micro switch.




0.5 W out into 50 ohm load through LPF (5 v/division;  10 V P-P).  Supply voltage = ~12 V


Initial results can be seen from the photos on the previous page.  The transistors do amplify in this circuit and I can get a nice waveform if I adjust the gate bias (R5) voltage to give a maximum 1 W output into 50 ohms.  Adjusting the bias to exceed this power level causes the scope trace to turn ugly showing that bias has shifted the transistor off the linear portion of its load-line.   What needs to be done to determine the operating limits is to vary the input level to the MOSFET gate while maintaining the bias so the transistor is operating in its range and at different supply voltages.  This is a good reason to buy a nice signal generator  J

With the simple setup shown in the schematic at a supply voltage of 13.6V, PA voltage gain as measured with the scope probe, was determined to be approximately 15 db.  Vin = 4 V P-P and Vout into 50 ohms = ~25 V P-P.

After this test, I thought about improving the impedance match into the MOSFET gate and buffering the output of the crystal oscillator.  I adapted a section of a circuit from one of my Softrock transmitters and came up with this:

This circuit did not do much to improve the waveform going into the gate of the MOSFET but it did permit higher output power with a nice sine wave after the LPF.  I could easily obtain  1.5 W out with a 13.6 V supply and a MOSFET gate bias voltage of 4.0-4.1 V (measured with open source).





I also tried reducing the bias on the oscillator transistor Q1 base by lowering the value of the base to ground resistor to about 2/3 the original value.  This did not have any noticeable effect.




Breadboard with the added buffer amplifier and 9:1 input transformer to the MOSFET gate


I do not consider this circuit to be a useable transmitter.  It’s a test jig for performing  a rudimentary check on RF MOSFETs or picking a matched pair.   As a transmitter the circuit is not appropriate: the leads are too long; there is no thermal protection in the bias, etc.  For these reasons I am not going to invest effort in testing at a higher frequency.    However, I did listen to the 7.3 MHz output (into a dummy load) on the station transceiver and, in fact, the CW sounded just fine, no key clicks, shifting notes or other QSD.

After a suitable number of cups of coffee the next morning, I realized that L1, R6 and C2 are to zero beat (pull) the crystal frequency when operating CW and are not needed for a test jig.  If you remove them, it may be necessary to increase the value of C1 .




Planned improvements:

  1.  Add an ammeter to be able to determine DC efficiency.
  2. Regulate the bias voltage supply.
  3. Compare RF amp results using different switching power supply transistors
  4. Determine the effect of increasing the supply voltage to 24 V.


I recommend checking out VA3IUL’s website where there are many circuits and ideas for projects.  Thanks to Iulian for his assistance with this little project.


Earl, 4Z4TJ / VA6TJ