AmateurRadio.com

In the film "Willy Wonka and the Chocolate Factory" there is a scene where the lucky children (and parents) enter the "Land of Candy" where everything is edible and they run around grabbing a taste of everything. I am beginning to know how they felt.

Amateur radio has so many different things to try and over the last year I have found myself jumping around having a dabble at new things. Doing this and time being scarce has inevitably impacted the HAB payload and other Arduino projects. I have also neglected some of my previous satellite monitoring activities.

I had been regularly decoding the FUNCube-1 (AO-73) telemetry and uploading packets to the data warehouse (see earlier posts). To do this I had been using a discone in the loft and a FUNCube Dongle on the ageing main computer in the house.

This computer was on 24/7 but I couldn't leave the FUNCube dashboard running continually as the processor load would cause the noisy fans to kick in, besides for most of the day there wasn't a receivable pass. So I would just start up the dashboard when needed which meant remotely logging in from work. Due to an increasingly busy work load I would often forget or be unable to start it up and have got out of the habit. I therefore missed many opportunities to climb up the uploading ranking chart (it is really for the science honest!)

Of late there have been a large number of new satellites launched including the UKube-1 and the QB50 satellites which have modules and transponders as part of the FUNCube project.

Catching up with news after the holiday to Skye I noticed the announcement that an enhanced version of the FUNCube decoder dashboard has been released promising improved performance. The dashboard will also capture and upload (but not display) the FUNCube-2 telemetry transmitted from UKube-1

Looking at the FC1 upload ranking list I saw I had dropped down significantly and decided it wasn't acceptable!


As part of my antenna upgrade I have put up the X-50 dual-band collinear on the top of the pole feed with nice low loss RG213. This is currently connected to the FUNCube Dongle Pro+ dongle on the shack laptop, with the latest dashboard software installed.



It has been running 24/7 for the majority of the last week and has captured close to 2000 telemetry packets from FC1 a significant performance increase compared to my earlier set up, and I have now surpassed the 10,000 packet milestone (currently 11,626). I have also uploaded over 500 telemetry messages received from the FUNCube-2 on UKube-1. I have actually received more but a fault in the warehouse meant a lot were rejected due to a incorrect data field.

The FC2 subsystem on UKUBE-1 may not be enabled on every pass while the satellite is commissioned and the FUNCube team will be releasing an updated dashboard shortly for when it is operating full time.

At present both satellites are passing one after the other, with UKube-1 gradually gaining. So as FC1 goes LOS (loss of signal) UKube-1 rises elsewhere for AOS (acquisition of signal)

On one pass yesterday I thought I would capture some screen shots and show how I've got the dashboard set up for both payloads.

As already mentioned the existing dashboard can be used to receive both FUNCube-1 and 2, if using the FUNCube Dongle Pro+ by setting the central frequency to 145.905MHz and adjusting the upper and lower filter curtains both payloads can be received.

On the Orbitron prediction software you can see FC1  is overhead, with UKube-1 over the North pole.


The reception window on the dashboard is limited by moving the curtains. I have the lower one set at 145.906MHz just enough to filter out the centre SDR spike,  the upper one is at 145.945MHz. The telemetry signal on FC1 is at 145.935MHz but due to the Doppler effect the received frequency will vary above and below this nominal value, 10kHz either size is sufficient to compensate.

If you were just interested in one satellite you would move the lower curtain to around 10kHz below the nominal download frequency. However since UKube-1 is on 145.918MHz the lower curtain is set to below this again to compensate for the Doppler shift.

The resulting receive window will allow both to be received. However this does risks problems should QRM occur in the pass band as the decoder can lock on to this, luckily the improved dashboard software discriminates between the signal and noise much better than previous versions.

The dashboard below is receiving the FUNCube-1 signal (click to enlarge)
 

The data is being uploaded and checking the real time display on the warehouse confirms this (my old callsign M6GTG) however you might not show up every single time and the FUNCube-1 Flight Model tab must be chosen as seen below.


As the pass finishes and UKube-1/FC2 comes overhead and due to the omni-directional X-50 I don't need to change anything.


The dashboard soon detects the new signal at the lower frequency and begins decoding.


The received payload ID is shown in the bottom right of the dashboard


Again the upload can be confirmed by viewing the real time data page on the warehouse by selecting the UKube-1 FC2 Payload tab. It should be noted that it seems FC2 is sometime sending spurious data elements in the telemetry which the warehouse is rejecting so some uploads may not be displayed.


It is really that simple.
Andrew Garratt, MØNRD, is a regular contributor to AmateurRadio.com and writes from East Midlands, England. Contact him at [email protected].

Recent comments on the ON4KST 6m chat page tend to indicate that the summer's Sporadic-E season is rapidly drawing to a close...."time to move to 160?" ..."how long 'til Es season? " ..... "is that it for the year?". Peaking around early July, I'm always surprised at how rapidly the three-month propagation-party zips by and, as always, leaves us wanting just a little bit more.

Unlike the past several summers, I had no European QSO's this year. The July 27th VE6 - Europe event was as close as it came but who knows what might have been missed during some of those predawn propagation periods when most west coasters are still sawing wood. Ever-vigilant KL7KY was alert enough to find Europeans at 0300 his time, on two separate July occasions, making me wonder if the same thing might happen down here as well? After Kevin's over-the-pole success, I started all day and overnight scans of the northern Canadian beacon segment (50.010 - 50. 050) with the 756PROIII's versatile (non-squelched) scan mode and the yagi pointed at 035 degrees. Even considering my somewhat late-season start, I was surprised at how often the beacons were making an appearance, often popping-up late in the evening or in the middle of the night....without the scan, these conditions would normally go unnoticed. I probably began my scans too late in the season and next summer will begin earlier, about mid-June through mid-July, hopefully giving me a better chance for Europe. John, VE7DAY, has also expressed interest in pursuing this more diligently next summer as well and has even spoken of daily 0300 over-the-pole CQ's during the mid-season's peak period.

The season highlights for this summer are very few....contacts with LU5FF, BV2DQ, EA8DBM, several dozen JA's and one new U.S. grid for the FFMA struggle.










I still need 49 grids to have all 488 continental U.S. grids confirmed but at this year's rate I'll need to live until I'm 115.









Six meters may yet still hold a late-season surprise for us but if the fat-lady hasn't already sung then she's just behind the curtain ....clearing her throat.


Steve McDonald, VE7SL, is a regular contributor to AmateurRadio.com and writes from British Columbia, Canada. Contact him at [email protected].

I’ve been considering getting a Raspberry Pi for awhile.  Several folks have asked me if I would port my Arduino Keyer code to it.  So I decided to take the plunge and acquire a Pi from Newark / Element 14, along with some “fixins”.  I got the Model A Pi, along with a WiFi dongle, and a cute little enclosure.

Big Things Come in Small Packages

I didn’t realize just how small the Pi was until I held one in my hand.  It’s just amazing this is a full blown computer.  It’s quite a leap from the VIC 20, the first computer I used 30 years ago as a teenager.

Raspbian Installation

The Raspberry Pi was surprisingly easy to fire up.  I bought a 16 GB SD card locally and burned a copy or Raspian on it.  After plumbing up a monitor to the HDMI port and connecting a USB keyboard and mouse, the unit booted right up, displaying messages familiar to anyone who runs Linux.  A few minutes later I entered startx and I was in XWindows.  Of course I just had to bring up a terminal window and verify this was really a ‘nix box and run top.

Nifty Little Pi Enclosure

Now that I have my Pi humming away, what projects should I do?  As I’ve mentioned a few folks have inquired about porting my keyer code to the Pi.  Googling around I found someone has ported the Wiring development platform , which is the basis for the Arduino environment, to the Raspberry Pi and aptly called it Wiring Pi.  Naturally it’s not 100% compatible and it’s not as easy as just plugging in the Arduino IDE and uploading compiled code.  I’m debating whether to take this approach of getting the keyer code to run under Wiring Pi, or just start from scratch with good old C and gcc for the compiler. I could get the core functionality going and then port over parts of the code from the Arduino for ancillary functions, if it makes sense.  Certain things don’t make sense to port, like the CW memories code.  On the Pi you don’t have to deal with EEPROM like you do on the Arduino.  Anything that needs to be persistent across reboots can just be written to a good old file on the file system.  While certain things like persistent memory and sound support are easier on a Pi, deterministic and precise timing, which is needed for CW timing, is challenging on a multi-tasking environment like Linux.  This realtime kernel may be just the ticket.

Compared to the Arduino, there aren’t a whole lot of interfacing pins on the Pi.  To really get the power of this board you need to do I2C.  I’m thinking about what it would take to port my antenna tuner to the Pi.  That project uses I2C for controlling many relays, but there is also a need to monitor the voltages of the SWR bridge.  The Pi doesn’t have this capability natively, so an I2C device would be needed to supply this functionality.

All in all the Raspberry Pi is a versatile and powerful little board.  To get my feet wet I think I’m going to write a little bare bones C and see if I can get a basic keyer working and see where this takes me.  This is going to be fun.

 

Anthony, K3NG, is a regular contributor to AmateurRadio.com.

What do you do to complete these hamfest bargains? 3D printing for the win!

The best thing about it is that you can color-code the connectors, too! Finally, props to a CAD-ninja coworker for whipping up the beautiful SolidWorks model in a couple of minutes.

Ethan Miller, K8GU, is a regular contributor to AmateurRadio.com and writes from Maryland, USA. Contact him at [email protected].

Randy Hall, K7AGE, is a regular contributor to AmateurRadio.com , produces amateur radio videos, and writes from California, USA. Contact him at [email protected].

Using the strapped feeder to my Par 10/20/40m as my 472kHz antenna rather than my 2m/70cm feeder, the antenna current has nearly doubled with the antenna current meter now showing 30-33uA whereas it was 18uA before. This suggests ERP has increased by around 4-5dB (ERP proportional to I^^2), but we’ll see later. The Par antenna itself is lower than the 2m/70cm antenna and runs horizontally to a tree. Average height is around 3-4m AGL. The losses may be greater.

The picture shows the 472kHz coil used (a ferrite rod would be fine but since moving it is “lost”), the 472kHz homebrew transverter (left) and the 3C90 matching coil between transverter and antenna (towards centre, LHS of coil). The small meter measures antenna current and registered 18uA last night and 30-33uA now with the Par antenna with strapped feeders.

UPDATE 1420z: G8HUH (250km) is copying in daylight a full 8dB S/N better than last night. Encouraging.

UPDATE 1448z:  M0PPP (182km) seems to be coming in stronger than last night too and in broad daylight.

UPDATE 1700z:  M0PPP  is now spotting me at 1456z, 1538z and 1620z i.e. in daylight.   He was not copying me at all last night, so I think my signal IS stronger.

Roger Lapthorn, G3XBM, is a regular contributor to AmateurRadio.com and writes from Cambridge, England.