9 Jun 2012
VE7 Repeaters
Now 23 hours without sleep having arrived in Vancouver after a long flight from the UK. Currently in the hotel room trying to work some BC locals via Echolink connected repeaters. What I really need is SLEEP though!
7 Jun 2012
First country gets 472kHz allocation
Monaco is reported (by 3A2LF) to have allocated the 472-479kHz band to radio amateurs from May 18th as a secondary allocation with a maximum power of 1W EIRP. Others are likely to follow in the following 12 months, we hope.
FT817 replacement - 2 years away
The following (extract from a) post from Bryan KE6ZGP appeared on the FT817 Yahoo group in the last few days.
"Tom interviewed the Yaesu rep about their new FT-DX3000 and the FT-1D, when all was said and done he started taking questions, I went ahead and asked about a possible replacement for the FT-817. The rep then stated - due to some parts (like the LCD screen) either being no longer available or extremely hard to find, they will likely replace the FT-817 in a couple years. He wasn't sure when exactly, R&D hasn't started on anything, but the earliest we can expect to hear any solid talk is two years from now."Now I assume this data is good and the rep from Yaesu is properly informed. If so, then any replacement to the FT817 is at least 2 years away. This gives Elecraft a clear field for a couple of years with their new KX3. The only other QRP radio on the horizon is the Ten Tec Argonaut VI which is due out towards the end of the autumn this year.
Labels:
ft817,
ft817 replacement,
ft817 successor,
ke6zgp
6 Jun 2012
Hendricks QRP Kits
The BitX SSB transceiver on the QRP Kits website |
The future of HF amateur radio
There is no doubt that HF amateur radio is changing. Fewer people ragchew these days (do you agree?) and there is considerably less activity outside of contests, mirroring a change already seen on the VHF bands. More people are using digital modes instead of phone and there is much more use of software tools to detect DX, decode and encode CW, PSK31, etc. The hobby is changing: some of the new ways of operating are very good, but along the way we are in danger of losing something of the appeal of the hobby perhaps?
Now, there is also another factor: it is very likely we will have seen the end of active sunspot cycles once the present low peak of cycle 24 declines. Many of us who experienced the peaks of 1957 through to 1980 are very unlikely to experience similar ones in our remaining lifetimes. Propagation on HF may never be as good as the second half of the 20th century for another 100 years. There are also theories that HF propagation is not as good as it was, even assuming similar solar activity, as if the ionosphere is actually changing its behaviour.
Then there is the challenge of spectrum pollution. This is already a menace for many of the lower HF bands but even bands like 10m and 6m are affected.
So, the challenge now is to look to the future, positively, and see how the future of HF will be redefined. I have no idea what the next 10 years will bring, but I suspect the use of our HF bands will be quite different by the 2020s.
Now, there is also another factor: it is very likely we will have seen the end of active sunspot cycles once the present low peak of cycle 24 declines. Many of us who experienced the peaks of 1957 through to 1980 are very unlikely to experience similar ones in our remaining lifetimes. Propagation on HF may never be as good as the second half of the 20th century for another 100 years. There are also theories that HF propagation is not as good as it was, even assuming similar solar activity, as if the ionosphere is actually changing its behaviour.
Then there is the challenge of spectrum pollution. This is already a menace for many of the lower HF bands but even bands like 10m and 6m are affected.
So, the challenge now is to look to the future, positively, and see how the future of HF will be redefined. I have no idea what the next 10 years will bring, but I suspect the use of our HF bands will be quite different by the 2020s.
Photo editing - try Gimp
Gimp screenshot example from the Gimp website |
Labels:
gimp,
photoshop elements
5 Jun 2012
My thanks
Thank you so much for everyone's support yesterday when I was feeling quite down: nine replies on the blog and as many again directly by email is true support in the best spirit of amateur radio. The message is "don't let the idiot's beat you down", which will be my motto.
Ours is a GREAT hobby and I guess we have to accept there will be a few bad apples in the orchard. Anyway, firmly back in gear here with a list of projects far too long to do any time soon. Several interruptions likely in the next few weeks but I'll be getting my teeth into some good ones very soon.
Ours is a GREAT hobby and I guess we have to accept there will be a few bad apples in the orchard. Anyway, firmly back in gear here with a list of projects far too long to do any time soon. Several interruptions likely in the next few weeks but I'll be getting my teeth into some good ones very soon.
Labels:
thank you
Very simple Spectrum Analysers
On the GQRP Yahoo group recently there was some further mention of very simple spectrum analysers with some links to very impressive, yet simple circuits. I was recently offered an old HP analyser but it was very large, very old and quite expensive: I did not want something that might soon go wrong and take up a lot of space, but I still need something simple to allow basic spectrum measurements. Nothing too accurate is needed, just an indication of harmonic levels and the like.
In essence, a spectrum analyser boils down to a receiver with a swept oscillator with its output connected to a display such as an oscilloscope. In its most simple form it could be just a crystal set in which the tuned circuit is replaced by a varicap tuned circuit with the rectified output going to a display. The voltage applied to the varicap is a sawtooth waveform (for example derived from a 555 timer IC) which also drives the x axis of the scope: this makes the tuned circuit sweep a band of frequencies over a second or so with the receiver's rectified output connecting to the Y axis of a scope. The resulting scope trace is then a picture of the band being scanned.
An example of a simple spectrum analyser in a small mint tin is at Alan VK2ZAY's site http://www.vk2zay.net/article/256. Although Alan was doing this design for fun, the resulting circuit based around a VHF super-regen receiver in the IF is quite remarkable. It is a seriously useful piece of test equipment. This is the YouTube video of Alan describing the circuit:
An earlier simple design is available at http://www.qsl.net/n9zia/spec/Homebrew_Spectrum_Analyzer.pdf which uses the sweep voltage to control the local oscillator of an existing receiver.
More complex designs have wide dynamic range, more linear displays and narrow IF filters to improve the resolution. "You get what you pay for", but simplicity is still capable of providing something very useful.
In essence, a spectrum analyser boils down to a receiver with a swept oscillator with its output connected to a display such as an oscilloscope. In its most simple form it could be just a crystal set in which the tuned circuit is replaced by a varicap tuned circuit with the rectified output going to a display. The voltage applied to the varicap is a sawtooth waveform (for example derived from a 555 timer IC) which also drives the x axis of the scope: this makes the tuned circuit sweep a band of frequencies over a second or so with the receiver's rectified output connecting to the Y axis of a scope. The resulting scope trace is then a picture of the band being scanned.
Shortwave scan on the VK2ZAY mint tin spectrum analyser |
An earlier simple design is available at http://www.qsl.net/n9zia/spec/Homebrew_Spectrum_Analyzer.pdf which uses the sweep voltage to control the local oscillator of an existing receiver.
More complex designs have wide dynamic range, more linear displays and narrow IF filters to improve the resolution. "You get what you pay for", but simplicity is still capable of providing something very useful.
Labels:
555,
spectrum analyser,
timer ic,
vk2zay
4 Jun 2012
A very sad day
Do you get days when everything goes wrong? Today was one of these for me.
A few weeks ago I suggested, after a long 5 day outage, that the RSGB LF-reflector migrated to a Yahoo Group. In my experience Yahoo groups are great: messages, files and photo storage and a great way to share and archive information with others of like mind. In over 15 years I have rarely had problems with any of the groups to which I belong.
After a few weeks, the group leader G3WKL decided to make the move to a Yahoo group having "taken the temperature" of the original group members. Then the "fun" began: a few people objected and started a flame war and I was centre stage of the hate, in particular from one particularly nasty and forthright individual. I could name him but will not stoop so low.
My intentions were good: I wanted to let people know that all they did with the original Blacksheep mailing list could still be done, but so much more too. Things like archiving of messages, 100GB of both file and photo storage etc.
The resulting avalanche of nasty and ill-informed posts, many of which were directed at me, has frankly sickened me. My faith in the hobby has been shattered by the bad feeling and unkindness of a few ill-informed individuals.
Amateur radio is usually a friendly and helpful community but in the last few days I have seen an altogether different and darker side of it, one which shames the community.
To be honest, I have never been nearer to throwing in the towel and taking up another hobby. This is indeed a very sad day.
A few weeks ago I suggested, after a long 5 day outage, that the RSGB LF-reflector migrated to a Yahoo Group. In my experience Yahoo groups are great: messages, files and photo storage and a great way to share and archive information with others of like mind. In over 15 years I have rarely had problems with any of the groups to which I belong.
After a few weeks, the group leader G3WKL decided to make the move to a Yahoo group having "taken the temperature" of the original group members. Then the "fun" began: a few people objected and started a flame war and I was centre stage of the hate, in particular from one particularly nasty and forthright individual. I could name him but will not stoop so low.
My intentions were good: I wanted to let people know that all they did with the original Blacksheep mailing list could still be done, but so much more too. Things like archiving of messages, 100GB of both file and photo storage etc.
The resulting avalanche of nasty and ill-informed posts, many of which were directed at me, has frankly sickened me. My faith in the hobby has been shattered by the bad feeling and unkindness of a few ill-informed individuals.
Amateur radio is usually a friendly and helpful community but in the last few days I have seen an altogether different and darker side of it, one which shames the community.
To be honest, I have never been nearer to throwing in the towel and taking up another hobby. This is indeed a very sad day.
Labels:
groups,
lf-reflector,
rsgb,
yahoo
3 Jun 2012
472kHz designs
GW3UEP's website has some useful new designs for 25 and 100W transmitters for the new 472-479kHz band which is expected to become available Jan 1st 2013. These designs use very standard and easily available parts and are very simple to duplicate. They would be an ideal starting point for anyone wanting to get going on the new band in 7 months time.The designs are based on earlier ones for 500kHz.
Part of GW3UEP's simple TX for 472kHz |
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