General – LF and CW Adventures

SDR or IC7000 … how do they compare?

I have had a NooElec SDR dongle and upconverter for a while now. Up until the last few days I have just “tested” it and checked out the software but never got too serious about receiving using the SDR for CLEs and NDB hunting.

As mentioned in the previous post, I have exhausted the reach of my current receive systems, gaining only a few new NDB stations (for example) when propagation conditions are exceptional. The SDR looks like a new tool to allow me to expand my listening times.

I like HDSDR and its features suit my current needs. Recording overnight reception for analysis later is what interests me right now. I played around with this last night and found that the reception is similar but possibly not quite as sensitive as my IC-7000 and Spectran using the same antennas. I’ll need more hard data and some experimentation to be convinced that is true.

The recording issue leaves me with a problem … I use a laptop for the shack computer as I can run on battery power to eliminate charger noise while I listen. Recording would only be available for as long as the battery lasted which is under 2 hours. The storage required for 1 hour of recording at the second lowest bandwidth is about 6.7 GB and that is problem #2 … I have only 28 GB free on the laptop drive (3 hours or so without crashing the computer).

Potential solutions include re-building one of my desktop computers and stocking it with some TB drives (a serious undertaking) or adding external drive capacity and power supply filtering to the laptop.

I’ll start by testing the external drive setup with my existing equipment to see if it is worth an investment. I worry about using a USB 1 connection for data transfer (older laptop), this may become an issue so I need to test this further.

PS: I also looked at KiwiSDR as well. I live in a remote place and it would be interesting to run a listening station!

UPDATE:

After a few days of recording and comparing levels on all antennas I have concluded that the differences in S/N and signal level is smaller than I can measure. Each antenna has a different “best frequency range” so I must keep that in mind for future reference!

Some “new” reading material …

I had to take time off from my vacation to go back to work last week and found the following reading material in my mailbox, thanks to the newly retired colleague that thought of me when cleaning up to move south.

There are three images (use the arrows!).

They are 1960’s era UK wireless magazines absolutely packed full of advertising with a few technical tidbits thrown in. The previous owner(s) had removed some of the best tech pages but what was left is really great to read.

The cover art is exceptional. Modern magazines are all about the photograph, these are excellent hand-drawn renderings.

Computers and signals

I’ve dabbled with computers, SDR systems and software for spectrum analysis on my HF radio for a few months (more off than on) and have not really thought too much about these tools. Then the computer decided that the HDD was no longer a HDD and stopped working completely last month.

When this happened I said “Oh well, I don’t use it for too much so it can sit on the shelf for a bit”. This turned out to be the opposite of what I really should have done!

I’m at a point in my NDB hunting career where I have heard most of the signals that are audible on a normal evening. On quiet nights with good propagation I’ll hear more but I feel it’s time for some new strategies.

One is building a loop to null the “loud ones” (it’s on the project list) and another is digital signal processing (DSP).

Weak signal detection using DSP can allow me to “see” the signals that I cannot hear well (or at all). I can also use programs that will decode digital signals or display QRSS (slow speed CW) easily. Recording is also possible with these programs so I don’t have to stay up late every night!

So now I’m at a standstill as my computer is not working. I ordered a new (old PATA style) HDD and it’s on the way. Once here, I’ll rebuild the computer using some backups I have (you have backups don’t you?) and re-install other programs. I should be back up to speed by month end (I hope).

Amateur Radio … I’m changing gears!

Hmm … Yet another blog … does the world need this?

Probably not but I need a way to organize my thoughts and document my projects in the LF/MF world as well as my adventures in (re)learning CW.

Living at the end of the [repeater] network gives me fewer VHF options for QSOs. There are few hams in the general vicinity and mountains are blocking access to those that are closest.

Since the 1980’s I’ve:

played with the amateur satellites (ISS, MIR, OSCARs, etc) … timing is everything but being in the north does not help,
help maintain repeater networks on mountaintops (Yukon, Northern BC) … exciting, but that thrill is fading as I age,
managed communications on long distance (100+ mile) running races … learned a lot about logistics and being prepared,
participated in search and rescue exercises and real events … working in military operated searches was really helpful in making me a more professional operator
made HF contacts around the world … usually 80, 40 and 20 Meters
contested in my spare time … what spare time?

Some day I may be up for the challenge of EME.

For now I’m trying to step away from the usual world of VHF FM voice/data and move into more exciting territory.

Chasing NDBs and operating on the newer top bands for Canadian amateurs is interesting, technically challenging and less populated thus making contacts more valuable … that sounds like fun to me!