 |
HK1NA (worked today) operating CQWW |
Some of the operating skills were amazing: PJ4X was working stations at a rate of one every 5 seconds. He spoke so crisply and quickly that by the time I'd called he'd already worked another station!
28 Oct 2012
More DX on 10m today
This must rank as one of the most fun CQWW DX contests I've taken part in. Plenty of DX could be worked with just 5W SSB from the FT817 and my small Homebase-10 halo today and yesterday. If anything conditions were better on 28MHz today than yesterday.
Stations worked include LR3M, LP1H (Argentina), C5A (The Gambia), HK1NA (Colombia), CR2X, CR3A, CT3HF (Azores), CN3A (Morocco), ER3AU (Moldova), A65BB (UAE), 3V8BB (Tunisia), ZW5B, ZZ2T, PY1NX, PS2T (Brazil), EY8MM (Tajikistan) plus loads of US, Canadian and other stations. My ears are sore with SSB signals! I have now filled my third page of contacts in the logbook.
Some of the operating skills were amazing: PJ4X was working stations at a rate of one every 5 seconds. He spoke so crisply and quickly that by the time I'd called he'd already worked another station!
Some of the operating skills were amazing: PJ4X was working stations at a rate of one every 5 seconds. He spoke so crisply and quickly that by the time I'd called he'd already worked another station!
First signals seen on JT9-2 mode
On 500kHz this morning PA0A and G3ZJO were testing with the new JT9-2 weak signal mode. Not yet copied Eddie, but PA0A was coming through well. This is a screenshot with his decoded signal overlaid.
 |
| 500kHz first JT9-2 signal received |
Choice DX on 10m SSB today
The CQWW DX Contest continues to brighten up things on 28MHz SSB, although the competition is fierce for some of the rarer stations.
Some DX is surprisingly easy to work though, responding after just a couple of calls with QRP. My 5W QRP SSB got through to EY8MM and A65BB but failed (so far) to work XV1X (Vietnam) or JT1BV (Mongolia).
 |
| XV1X QSL card |
27 Oct 2012
JT9: a new digital mode for MF and LF
Hot news from Joe Taylor K1JT on the RSGB LF Yahoo group this evening about a new 9-FSK digital communications mode (for 2-way QSOs rather than beaconing) optimised for MF and LF bands. With winter approaching and better LF conditions, this is an exciting development.
 |
| The wide graph display for JT9 |
"I invite you to try a new digital mode called JT9, designed especially for making amateur QSOs at MF and LF. JT9 uses the structured messages introduced in 2003 for the JT65 mode, now widely used for EME and for QRP operations at HF. JT9 can operate at signal levels as low as -27 dB (in a 2500 Hz reference bandwidth), with one-minute timed transmissions. It also offers slower transmissions of 2, 5, 10 and 30 minutes duration, and the slowest mode can decode signals as weak as -40 dB. With one-minute transmissions, submode JT9-1 has a total bandwidth of just 15.6 Hz -- less than one-tenth the bandwidth of a JT65A signal. The other submodes are narrower still: a JT9-30 signal occupies about 0.4 Hz total bandwidth.
Note that these JT9 sensitivity levels are comparable to or better than those of WSPR, which uses simpler messages and is not intended for making 2-way QSOs. JT9 has much higher throughput and reliability than QRSS CW, including DFCW modes.
JT9 is implemented in an experimental version of WSJT called WSJT-X. Some further details can be found at http://www.physics.princeton.edu/pulsar/K1JT/WSJT-X_Quick_Start_Guide.pdf , and an early version of WSJT-X can be downloaded from
http://physics.princeton.edu/pulsar/K1JT/WSJTX_01r2695.exe.
Please note: WSJT-X is in an early development stage. A number of improvements and enhancements are already in the works, and others will surely be added.
Your feedback will be much appreciated!
-- 73, Joe, K1JT"
CQWW SSB DX contest 2012 (28MHz) - a recording
In 5 years or so, this day will seem like a dream with 10m probably dead and devoid of activity. So, for posterity, I made a sound recording late this morning of the 10m band as I tuned across it and later this video at around 1630z.
Here is an earlier sound recording CQWW SSB DX contest 1125z October 27th 2012. Recorded near Cambridge, UK. Feel free to share/use this recording and video. I only made them for posterity so I can remember, in years to come, what 10m was like at a sunspot peak.
Chromebooks?
UK retailers include PC World, Amazon and John Lewis. They seem to be selling FAST.
Although I am not sure why, this PC really appeals to me: it is simple, small and effective. The local machine remains uncluttered and safe to use as most of the applications work remotely "in the cloud" although Gmail, Goodle Docs and lots of other apps will work without an internet connection too.
Has any reader used a Chromebook? What were your impressions?
26 Oct 2012
VLF DX radiated test results
My days long, continuous carrier test with G3WCD (32km) and G3ZJO (around 50km) around 8.977188kHz ended yesterday. I was using my 20m spaced earth electrodes with 5W out of the PA. The test was to see if anything at all could be detected well beyond the 6km I can repeatably obtain with QRSS3 earth-mode (through the ground) communications. Despite the hint of a signal a couple of times on the G3WCD 45uHz and 22uHz grabbers, these proved to be false signals and nothing was detected.
Using Spectrum Lab, locked to a VLF MSK signal I am able to measure my TX frequency with VERY great accuracy, in fact to an accuracy of less than 1mHz. What this showed up was that my crystal controlled TX drifted (very slightly by HF VFO standards) about 13mHz over the 4 days of the test. Starting frequency was around 8.977177kHz and the final frequency 8.977190kHz. With shack temperature variations it may have moved slightly higher or lower too.
When the RX stations are looking for a very very weak signal in a bandwidth of 22uHz this means the signal is only "within band" for the FFT software to analyse for a brief period before drifting out of the measuring "bucket". To have ANY chance it will be essential for me to lock the TX frequency so that it stays within a few uHz over a period of days. This could be done using a GPS reference signal or using Spectrum Lab. It is the latter that I shall be trying - receiving a VLF MSK signal on one antenna as the reference, then using SL to synthesise the continous TX carrier which is transmitted on a second antenna.
In reality to get 32km on VLF with my set-up was always a "long shot", but all parties agreed it was worth trying and we have all learned a lot in the process. Experimentation is the name of the game and failure is as important as success.
It may be some time before I try the long range VLF tests again: I hope to have over 100W next time and a super-stable TX signal. Who knows, we might just succeed next time.
For information on these software packages (all free) that I use at VLF see https://sites.google.com/site/sub9khz/software .
Using Spectrum Lab, locked to a VLF MSK signal I am able to measure my TX frequency with VERY great accuracy, in fact to an accuracy of less than 1mHz. What this showed up was that my crystal controlled TX drifted (very slightly by HF VFO standards) about 13mHz over the 4 days of the test. Starting frequency was around 8.977177kHz and the final frequency 8.977190kHz. With shack temperature variations it may have moved slightly higher or lower too.
When the RX stations are looking for a very very weak signal in a bandwidth of 22uHz this means the signal is only "within band" for the FFT software to analyse for a brief period before drifting out of the measuring "bucket". To have ANY chance it will be essential for me to lock the TX frequency so that it stays within a few uHz over a period of days. This could be done using a GPS reference signal or using Spectrum Lab. It is the latter that I shall be trying - receiving a VLF MSK signal on one antenna as the reference, then using SL to synthesise the continous TX carrier which is transmitted on a second antenna.
In reality to get 32km on VLF with my set-up was always a "long shot", but all parties agreed it was worth trying and we have all learned a lot in the process. Experimentation is the name of the game and failure is as important as success.
It may be some time before I try the long range VLF tests again: I hope to have over 100W next time and a super-stable TX signal. Who knows, we might just succeed next time.
For information on these software packages (all free) that I use at VLF see https://sites.google.com/site/sub9khz/software .
25 Oct 2012
My 10m halo - soon time for an overhaul
After the CQWW DX contest this weekend I plan to take down my Homebase-10 halo and rebuild it. The birds have managed to tear away at the nylon rope supporting the nested 6m halo and the wooden supports now look a bit weather beaten.
So, I plan to replace the wooden cross frame supports with PVC pipe or fibre glass rods and re-do the wire elements. These have been up in all weathers for around 4 years now, so a few pounds on a remake is justified. The antenna works so well and is so small that I cannot think of a better antenna for the 10m band short of going to a beam which would be huge by comparison and need a rotator. The neighbours are quite used to it too, which is good.
So, I plan to replace the wooden cross frame supports with PVC pipe or fibre glass rods and re-do the wire elements. These have been up in all weathers for around 4 years now, so a few pounds on a remake is justified. The antenna works so well and is so small that I cannot think of a better antenna for the 10m band short of going to a beam which would be huge by comparison and need a rotator. The neighbours are quite used to it too, which is good.
Ten-Tec Argonaut VI latest
Ten-Tec is working on a new Argonaut transceiver called the Argonaut VI. Details remain sketchy but at K4SWL's website http://qrper.com/tag/model-539/ there is some news that 25 units are going through a pilot run currently with production likely towards the end of the year.
There are not enough details available to make any judgement on this new QRP transceiver. As far as I can find there is nothing at all about it on the Ten-Tec website. Some rumours are that it will NOT cover 12m and 6m and neither will it support 10m FM. Who would produce a brand new HF radio without at least all 80-10m inclusive bands and modes?
Unless the price is very attractive and the unique features substantial, then I just cannot see it competing well against the 11 year old FT817 and the new Elecraft KX3. The pictures seen so far show a simple looking radio, some would say plain, but with what is supposed to be a very decent receiver along the lines of the Ten-Tec Eagle.
What's cooking Ten-Tec? Are you still going ahead with this transceiver? If so, please can we have some firmed-up specs and prices?
 |
| A photo of the Argonaut VI on the K4SWL website (linked) |
Unless the price is very attractive and the unique features substantial, then I just cannot see it competing well against the 11 year old FT817 and the new Elecraft KX3. The pictures seen so far show a simple looking radio, some would say plain, but with what is supposed to be a very decent receiver along the lines of the Ten-Tec Eagle.
What's cooking Ten-Tec? Are you still going ahead with this transceiver? If so, please can we have some firmed-up specs and prices?
24 Oct 2012
CQWW DX SSB contest this weekend
Although not a serious HF contester - I have never submitted a log - I do enjoy a fling in the CQWW DX SSB contest at the end of October each year, usually on 28MHz.
The most I can run is 5W pep but, if conditions hold up, there should be little problem in working stacks of US and Canadian stations as well as loads of others worldwide. This year I have a speech processor which appears to make a good 1-2 S-points difference and makes working DX much easier.
Especially towards the end of the contest there are plenty of big contest stations looking for new contacts. If you want to work some good DX plus new US states and Canadian provinces, then this coming weekend will be your best chance. In my experience running QRP SSB is no barrier at all to working LOTS of DX in this contest.
Some people love contests on HF and VHF and others hate them. Personally, I am happy to enjoy the DX opportunities they provide and tolerate the heavy band usage they bring, albeit for 48 hours in the case of the CQWW.
Exchange is report and CQ zone. In the UK we are zone 14, so a typical report would be "5914"
The most I can run is 5W pep but, if conditions hold up, there should be little problem in working stacks of US and Canadian stations as well as loads of others worldwide. This year I have a speech processor which appears to make a good 1-2 S-points difference and makes working DX much easier.
Especially towards the end of the contest there are plenty of big contest stations looking for new contacts. If you want to work some good DX plus new US states and Canadian provinces, then this coming weekend will be your best chance. In my experience running QRP SSB is no barrier at all to working LOTS of DX in this contest.
Some people love contests on HF and VHF and others hate them. Personally, I am happy to enjoy the DX opportunities they provide and tolerate the heavy band usage they bring, albeit for 48 hours in the case of the CQWW.
 |
| CQ zones map |
Subscribe to:
Posts (Atom)
