eQSL card for JT9-1 QSO |
10 Apr 2013
My first QSL card for a JT9 QSO
Labels:
eqsl
Sporadic-E season
We are now approaching the summer sporadic-E season in the northern hemisphere with excellent 10m, 6m and 4m (plus 2m on a few occasions) propagation across Europe, the Middle East and North Africa and sometimes far beyond.
On 6m and 10m it is possible to work out to around 2000 miles quite easily with very simple omni-directional antennas and a few watts by single or multi-hop Es.
With some luck much further is possible: a few summers back I recall the thrill of working the USA on 6m with 2.5W out from the FT817 (via a coax cable with around 3dB loss) to a V2000 vertical. ERP was just over 1W. Of course CW was used for this QSO.
Keep an eye out on these bands in the next few months as you may be surprised what can be copied. Better equipped QRO stations will be working South America, deep into Africa and Japan on 6m. Even when the sunspots don't play ball, we'll still have summertime Es. Half the fun is the surprise openings to distant places that appear and sometimes disappear within a few minutes. At other times the lower VHF bands can be wide open with S9 DX signals for hours and hours.
On 6m and 10m it is possible to work out to around 2000 miles quite easily with very simple omni-directional antennas and a few watts by single or multi-hop Es.
With some luck much further is possible: a few summers back I recall the thrill of working the USA on 6m with 2.5W out from the FT817 (via a coax cable with around 3dB loss) to a V2000 vertical. ERP was just over 1W. Of course CW was used for this QSO.
Keep an eye out on these bands in the next few months as you may be surprised what can be copied. Better equipped QRO stations will be working South America, deep into Africa and Japan on 6m. Even when the sunspots don't play ball, we'll still have summertime Es. Half the fun is the surprise openings to distant places that appear and sometimes disappear within a few minutes. At other times the lower VHF bands can be wide open with S9 DX signals for hours and hours.
Labels:
es,
sporadic-e
RSGB UK VHF/UHF Activity Contests - Tuesday nights
This year I keep forgetting to have a go in the regular UKAC contests every Tuesday evening. Activity in these is usually very good and they are great fun. Last year I went out in the field to a local high spot on both 70cm and 2m and achieved some good results with just 2.5W - remember I only found out the FT817 "3 blobs" setting was not 5W in December! Before moving in to my new East Anglian "hilltop" QTH - well it is 20m ASL :-) - I think I'll have to do some of these contests /P from the new back garden to see how the new location will be on VHF and UHF.
Labels:
ukac
Trying to fix an HP8640B sig gen ....and failing
The disconnected shaft is just to the RHS of the YIG oscillator |
You forget how USELESS 1960s and 1970s designs were in terms of ease of manufacture and repair. To get at the part, it looks like you have to take apart about 1 zillion screws and plastic cog wheels, and all because the designer didn't put the control about 5mm to the left, in which case none of these complicated mechanical arrangements would have been needed! These days, where competition, manufacturing and repair costs matter, the design would not be so unnecessarily complicated. After trying to join the 2 pieces together for nearly an hour, I gave up. In the coming days I'll return the 8640B to its owner and I expect he'll have the manual and the patience to fix it. My eyesight is also not as good as it was and that didn't help.
The tiny Elecraft XG3 signal generator (about the size of a pack of cards) would do all I need (and a lot more) and I think will be a good investment. It also weighs about 1/100th the weight of the 8640B. I am not after a signal generator with professional calibration and noise floor performance, just a simple way of checking the performance of simple receivers.
Unless absolutely necessary KISS - keep it simple stupid. This applies as much to professional gear as to amateur gear. Don't make life harder than it need be.
9 Apr 2013
The KD1JV Survivor 75/80m SSB transceiver
http://www.qrpkits.com/images/survivor04a.jpg |
The specs are:
- ~10W pep @ 13.8V
- 0.2uV receiver sensitivity
- 5 pole crystal ladder filter for selectivity
- 325 or 175 kHz tuning range, selectable at build
- Coarse and Fine tuning controls
- 8 ohm - 500 mW speaker output
- SSB, CW, and, "TUNE" mode
- 50mA Rx current (with optional Digital Dial)
- Inexpensive electret microphone input
- All through hole construction
- Professional silk screened and solder masked pcb
- Full aluminum chassis w/bail, cutout for optional digital dial
- Small size, 6" x 4" x 1.5"
- Assembled weight, w/dd: 330g./11.6 oz.
- 13.8 @ 2A, min. recommended power supply
Labels:
hendricks kits,
kd1jv,
survivor
Waters and Stanton respond on the FT817ND price increase
Today I received an email from Mark Francis, the sales director at Waters & Stanton PLC regarding the price of the FT817ND. You may recall I was suspicious that the price had risen when the Yen was weakening.
Mark explained that they are working to the tightest of margins these days and the price is basically set by Yaesu. He also pointed out that compared with 25 years ago we are getting a lot more for our money reminding me that back then the same money would have bought just a 2m FT290, whereas now we get a multi-band HF/VHF/UHF, multi-mode transceiver.
So, I stand corrected and accept what Mark has said.
I'm still looking around for the best deal on a new FT817ND to compliment my 12 year old FT817 that has been used just about every day since I bought it, but may well buy from W&S if they can match the best UK price.
Mark explained that they are working to the tightest of margins these days and the price is basically set by Yaesu. He also pointed out that compared with 25 years ago we are getting a lot more for our money reminding me that back then the same money would have bought just a 2m FT290, whereas now we get a multi-band HF/VHF/UHF, multi-mode transceiver.
So, I stand corrected and accept what Mark has said.
I'm still looking around for the best deal on a new FT817ND to compliment my 12 year old FT817 that has been used just about every day since I bought it, but may well buy from W&S if they can match the best UK price.
Labels:
waters and stanton,
yaesu
8 Apr 2013
Windows PC bargain
After some deliberation because of adverse reviews I ordered an Asus X101ch netbook from Amazon last week. When it arrived I added a 4GB class 10 SD card running Readyboost, deleted the junk software that was not needed, added MS Essentials virus protection and got going.
Well, for under £170 new I am blown away! This little machine is great: I have already used it for WSPR and had my first JT9-1 QSO with it on 20m just a few minutes ago. Spectran seems to work too. For web browsing it is just fine. The screen resolution and clarity are good. I have not had it slow down once and it has, touch wood, not crashed yet.
In fact my view is this is an excellent little 10.1 inch Win7 netbook for the things I need. Although intended as a second PC for /P use (optical beaconing and VLF in the field) it is currently being used as my main PC and working beautifully.
The windows experience index by the way is 3.2, which I think is average.
Well, for under £170 new I am blown away! This little machine is great: I have already used it for WSPR and had my first JT9-1 QSO with it on 20m just a few minutes ago. Spectran seems to work too. For web browsing it is just fine. The screen resolution and clarity are good. I have not had it slow down once and it has, touch wood, not crashed yet.
In fact my view is this is an excellent little 10.1 inch Win7 netbook for the things I need. Although intended as a second PC for /P use (optical beaconing and VLF in the field) it is currently being used as my main PC and working beautifully.
The windows experience index by the way is 3.2, which I think is average.
Labels:
asus,
readyboost,
x101ch
6 Apr 2013
ATV today
Amateur TV seems to be in decline these days with fewer and fewer interested. A well known ATV local G3KKD reports activity well down in recent times.
In a move aimed at reversing the trend G8YTZ has announced some Amateur Digital TV TX and RX modules. However, when visiting Justin's site I was flabergasted by the prices: over £700 for the transmitter and over £300 for the receiver! To attract newcomers surely some simple low cost modules retailing below £100 are needed.
In a move aimed at reversing the trend G8YTZ has announced some Amateur Digital TV TX and RX modules. However, when visiting Justin's site I was flabergasted by the prices: over £700 for the transmitter and over £300 for the receiver! To attract newcomers surely some simple low cost modules retailing below £100 are needed.
Another version of my 472kHz transverter (G8AGN)
Emeritus Prof Barry Chambers G8AGN from Sheffield (more usually a microwaves and nanowaves operator) has just sent me a couple of photos of his version of my 472kHz transverter that he's just finished. Unlike me, Barry sensibly put it in a decent sized aluminium box which will help reduce heat affecting the LO frequency stability.
I've lost count how many of these transverters, or variants thereof, have now been built but there must be a good few in use around the world now. I have still to box up the 137kHz version which was used a few months ago to span 250km with just the earth-electrode antenna.
G8AGN's version of the 472kHz transverter |
Labels:
472khz transverter
4 Apr 2013
Japanese Yen and radio gear prices
Today alone the pound-yen exchange rate has improved by over 4% in favour of the pound: basically Japanese goods are 4% cheaper than yesterday. UK dealers, please note: your customers are expecting product prices for Japanese radios to FALL please in the coming days and not rise!
The yen-pound exchange rate is now around 23% better (for purchasers of Japanese equipment) than a year ago, so some VERY good deals should be expected on Yaesu, Icom and Kenwood products.
The yen-pound exchange rate is now around 23% better (for purchasers of Japanese equipment) than a year ago, so some VERY good deals should be expected on Yaesu, Icom and Kenwood products.
3 Apr 2013
A couple of 20m JT9 QSOs in the log already
QSO with UA4PPQ on 20m JT9-1 today |
The mode certainly seems to be very useful on HF and takes up very little bandwidth - the scale on the screenshot above is in Hz above 14.078MHz, which is the USB dial frequency.
Using 2.5W to the end fed Par 10/20/40 antenna, but reports suggest much lower power would be fine too. Now QSYed to 28.078 MHz USB dial JT9-1 and calling CQ.
Labels:
jt9,
jt9-1,
weak signal modes
JT9 mode on HF
Julian G4ILO has been having some good success on HF with JT9 mode, so I am encouraged to have a go too. This afternoon I'll be firing up on HF, probably 20m.
Results with this mode on MF were very encouraging giving me my first international 2-way QSO (as opposed to WSPR report) some months back. The slower JT9 modes are similar to WSPR in terms of weak signal performance, but allow basic real 2-way QSOs similar to JT65 mode QSOs.
PSK reporter now shows JT9 spots, so it is possible to see where your signal is reaching even if a QSO does not result from a CQ call. The new JT9 Yahoo group is rapidly gaining members and is worth joining if interested in this new mode.
Recommended JT9 mode frequencies are:
10m 28.078MHz
15m 21.078
17m 18.104
20m 14.078
30m 10.130
40m 7.078
60m 5.2872
80m 3.578
160m 1.838
JT9 software can be downloaded from http://physics.princeton.edu/pulsar/K1JT/ As updates are still occurring it is best to check the site for later versions regularly. The user guide for all WSJT modes is worth reading.
Results with this mode on MF were very encouraging giving me my first international 2-way QSO (as opposed to WSPR report) some months back. The slower JT9 modes are similar to WSPR in terms of weak signal performance, but allow basic real 2-way QSOs similar to JT65 mode QSOs.
PSK reporter now shows JT9 spots, so it is possible to see where your signal is reaching even if a QSO does not result from a CQ call. The new JT9 Yahoo group is rapidly gaining members and is worth joining if interested in this new mode.
Recommended JT9 mode frequencies are:
10m 28.078MHz
15m 21.078
17m 18.104
20m 14.078
30m 10.130
40m 7.078
60m 5.2872
80m 3.578
160m 1.838
JT9 software can be downloaded from http://physics.princeton.edu/pulsar/K1JT/ As updates are still occurring it is best to check the site for later versions regularly. The user guide for all WSJT modes is worth reading.
1 Apr 2013
Good communications , or a lack of it in the NHS
My ham radio friend Julian Moss G4ILO has a brain tumour which he has been
successfully battling for over a year now. Recently he had a hospital
appointment to review treatment but reading his blog
I see yet again he has, like many I know, been given the "run around"
by the totally inept NHS service here in the UK.
This organisation needs radical surgery to get itself operating efficiently. Time and again it wastes money by messing up appointments, not having people where they should be, not having the data communicated between staff etc. It MADDENS me that sick people should be additionally stressed as a result of idiots who cannot run a business properly. They would save BILLIONS if patient records were shared electronically between health care staff (consultants, doctors, nurses, car service personnel and ambulance crews). It is not rocket science.
I have no fundamental issue with caring people trying to do their best, but they are totally hindered by the lack of decent communications at all levels.
In the 21st century, any organisation as bad as the National Health Service today would be in administration by now and its bosses sacked. NHS sort yourselves out!
This organisation needs radical surgery to get itself operating efficiently. Time and again it wastes money by messing up appointments, not having people where they should be, not having the data communicated between staff etc. It MADDENS me that sick people should be additionally stressed as a result of idiots who cannot run a business properly. They would save BILLIONS if patient records were shared electronically between health care staff (consultants, doctors, nurses, car service personnel and ambulance crews). It is not rocket science.
I have no fundamental issue with caring people trying to do their best, but they are totally hindered by the lack of decent communications at all levels.
In the 21st century, any organisation as bad as the National Health Service today would be in administration by now and its bosses sacked. NHS sort yourselves out!
Labels:
national health service,
nhs
Tripods for optical comms
The one I missed on eBay |
So, can readers make any recommendations for something similar?
My requirements are:
- Solid construction so it won't wobble around in wind with the optics and detector mounted on top.
- Some way of calibrating the direction to within a degree or so horizontally so that known directions can be confidently returned to. Ideally a large 360 degree marked scale.
- A way for leveling the head assembly so it can be aimed just above the horizon.
- Low cost as I am looking for an inexpensive solution (don't want the tripod and mount to cost much more than the rest of the kit, which is about £5-10 total!)
Labels:
optical 481THz,
tripods
30 Mar 2013
Low cost signal generators for QRP
Elecraft's XG3 signal generator |
The Norcal S9 signal generator |
Labels:
norcal,
s9,
signal generator,
xg3
Writing for radio magazines
In recent years I've written articles on a wide range of subjects, from VLF to optical, for several different radio magazines around the world. Now I don't do it for the money as I have a pension that covers my needs adequately, but I am surprised how poorly radio magazines do pay authors. This may be one reason why they find it hard to find new authors. I won't quote figures here as I don't want to embarrass anyone, but you have to write articles for the pleasure of doing so and not for the financial rewards, especially when tax is deducted.
One of the lowest payers appears to be the ARRL, which I find particularly surprising considering that QST must have one of the largest circulations in the world. Considering how long it takes to put a decent article together with illustrations and schematics (very many hours), the rewards are probably better if one stacked shelves at a local supermarket or worked on the local dustcart. It doesn't exactly encourage budding authors.
Times are hard and revenues in amateur radio magazines from adverts is probably falling, but reading QST, Practical Wireless and RadCom I see pages and pages of adverts that must bring in a decent amount. Maybe they'd get, and keep, more readers if they encouraged people to write interesting articles by paying a little more?
One of the lowest payers appears to be the ARRL, which I find particularly surprising considering that QST must have one of the largest circulations in the world. Considering how long it takes to put a decent article together with illustrations and schematics (very many hours), the rewards are probably better if one stacked shelves at a local supermarket or worked on the local dustcart. It doesn't exactly encourage budding authors.
Times are hard and revenues in amateur radio magazines from adverts is probably falling, but reading QST, Practical Wireless and RadCom I see pages and pages of adverts that must bring in a decent amount. Maybe they'd get, and keep, more readers if they encouraged people to write interesting articles by paying a little more?
Royal Mail - postal/packet costs
I'm frustrated and actually quite annoyed with Royal Mail. Have you visited the barely understandable Royal Mail website recently? All I wanted was to find out how much a small parcel (a book - the Scatterpoint compendium sold on eBay) would cost to send to Germany on Tuesday. It appears you now need a PhD to navigate the darn website and understand all the options. It is nearly as hard as trying to find a utilities tariff.
Having done a bit of eBay trading this last few weeks, I'm surprised how expensive it now is to send a small packet by post using Royal Mail or Parcel Force, even more so if sending it abroad. Unless I have misunderstood the incredibly confusing information on how to send a small packet to Germany, one weighing 760g costs an astounding £6.62. Go above 1kg and the rates are extortionate.
Thankfully we still have a helpful local post office staffed with people who try to sort this out for you. Not having receiving my doctorate yet, so unable to navigate the Royal Mail website, I'll have to ask the nice lady at the local PO for the price and a stamp.
Why can't we have a SIMPLE postage tariff based on weight and whether it has to go surface or by air? OK, add a few options if you want a guaranteed delivery.
Having done a bit of eBay trading this last few weeks, I'm surprised how expensive it now is to send a small packet by post using Royal Mail or Parcel Force, even more so if sending it abroad. Unless I have misunderstood the incredibly confusing information on how to send a small packet to Germany, one weighing 760g costs an astounding £6.62. Go above 1kg and the rates are extortionate.
Thankfully we still have a helpful local post office staffed with people who try to sort this out for you. Not having receiving my doctorate yet, so unable to navigate the Royal Mail website, I'll have to ask the nice lady at the local PO for the price and a stamp.
Why can't we have a SIMPLE postage tariff based on weight and whether it has to go surface or by air? OK, add a few options if you want a guaranteed delivery.
Labels:
ebay,
packets,
royal mail
28 Mar 2013
More Chinese QRP radios/kits
Chinese QRP kits and ready built radios seem to be everywhere. For example, see the KN-Q7A kit from http://www.crkits.com/ . This little 40m 10W or 20m 5W QRP SSB transceiver was designed by BA6BF. Reviews on eHam.net are good (4.9/5 with 8 reports) so this is no toy radio.
I have the feeling this is an enterprising Chinese amateur making a bit of money selling a few kits rather than a major Chinese manufacturer, gearing up for the big time. However, this IS coming. Unless the big boys like Yaesu and Icom move to low cost manufacturing locations like China for the bulk of their products then their days are numbered. Honestly.
http://www.crkits.com |
Amateur DX Europe to Alaska on VLF?
There has been some excitement over the last few days as Lawrence KL1X has seen a signal on 8.9700kHz when the noise was low that just could be coming from Uwe DJ8WX near Hamburg. He has tried to find out if this is a locally generated artifact, but it seems not.
In the coming weeks DJ8WX is moving his continuous carrier VLF transmitter (a long carrier is needed to be visible in the incredibly narrow bandwidths needed to see anything at all) down to 8.270kHz which is a clear frequency in Alaska. The Alaska VLF grabber is already active and, as soon as Uwe starts up, we hope to see a weak signal appear. If this happens this will be the very first confirmed reception of an amateur VLF signal from Europe in North America. The VLF receiver Lawrence uses is a small E-field probe antenna high up in a tree in a birch forest.
DJ8WX has been a very good signal on VLF here in the UK on my own receiving system (an 80m sq vertical loop feeding a preamp feeding a PC running Spectrum Lab with a special 424uHz bandwidth .usr file). I have not listened for Uwe recently as my loop is down but G3ZJO has copied him well in the last few weeks on his grabber.
If you are interested in amateur VLF then visit https://sites.google.com/site/sub9khz/ and check out the various preamps, grabbers and DX reports. It is possible to check out activity by looking at the various grabbers (VLF receivers linked to the internet) around the world.
KL1X grabber monitoring 8.270kHz for intercontinental amateur DX |
DJ8WX has been a very good signal on VLF here in the UK on my own receiving system (an 80m sq vertical loop feeding a preamp feeding a PC running Spectrum Lab with a special 424uHz bandwidth .usr file). I have not listened for Uwe recently as my loop is down but G3ZJO has copied him well in the last few weeks on his grabber.
DJ8WX's signal as seen on the G3ZJO VLF grabber |
I've left the Yahoo KX3 group
Since its early days, I've been receiving posts from the Yahoo KX3 Group, which is a group for people interested in this Elecraft radio. It was generating a huge number of daily posts: this month people have posted 1590 messages already! As it is now rather unlikely that I will purchase a KX3 - I simply cannot justify £1200+ for a fully loaded, if excellent, QRP transceiver - I decided today to leave this group. That still leaves plenty of other Yahoo group messages to read.
I'm not sure how others read Yahoo Group messages, but I always choose
" - Don't get notified of the latest happenings. Read messages only on the web."
I'd be unable to cope with several hundred, possibly thousands, of additional emails from groups each week. This option is always available when you join a Yahoo group, or you can do it later by editing your group settings.
I'm not sure how others read Yahoo Group messages, but I always choose
" - Don't get notified of the latest happenings. Read messages only on the web."
I'd be unable to cope with several hundred, possibly thousands, of additional emails from groups each week. This option is always available when you join a Yahoo group, or you can do it later by editing your group settings.
Voice of America cutbacks
In my early days as a shortwave listener, the various VOA transmitters around the world were popular station targets for reports. I even copied "this is the Voice of America, Monrovia" (West Africa) on my little 4 component SW crystal set. Now I see that the VOA is having to cut back transmissions because of the USA's budget issues. Like many shortwave broadcasters, VOA is feeling the pinch in hard times. The shortwave broadcast bands are no longer the same as they were back in the 1950s and 1960s: there are fewer and fewer English language transmissions to be heard nowadays.
As an aside, and I try to avoid political comments in this blog but feel compelled to share this, I read today that the audited costs of the Iraq war for the USA are an estimated $767bn. With ongoing healthcare and support costs the final figure will be well over $1trillion. All nations make mistakes and enter wars they later deeply regret, including the UK. What saddens me is the total WASTE this represents: Saddam was no saint, neither are the Talibhan in Afghanistan, but there has to be a better way to change nations. The phrase "swords into ploughshares" comes to mind. Jaw jaw is better than war, war. Just think how $1 trillion could have been better used.
As an aside, and I try to avoid political comments in this blog but feel compelled to share this, I read today that the audited costs of the Iraq war for the USA are an estimated $767bn. With ongoing healthcare and support costs the final figure will be well over $1trillion. All nations make mistakes and enter wars they later deeply regret, including the UK. What saddens me is the total WASTE this represents: Saddam was no saint, neither are the Talibhan in Afghanistan, but there has to be a better way to change nations. The phrase "swords into ploughshares" comes to mind. Jaw jaw is better than war, war. Just think how $1 trillion could have been better used.
Labels:
afghanistan,
iraq,
voa
Rectennas and solar energy
Recently I read about some interesting work on Rectennas, which are combined antennas and rectifiers used to detect microwaves and optical frequencies. The work suggested that very high efficiencies may be possible at optical frequencies (around 70%, possibly more) using nanotechnology leading to much more efficient power conversion of solar energy. The correct term for these would be Nantennas. At my new house (move coming up in a few months) I will be considering the installation of solar photo-voltaic panels, but wonder if I should wait a few years in case technical breakthroughs with Nantennas could revolutionise these?
Labels:
nantenna,
photovoltaic,
rectenna,
solar
Back from Lincoln
For the last few days we have been on holiday in Lincoln, staying at the Old Palace Hotel (I an highly recommend this) just below the marvelous cathedral. Our room was high up and looked due south and had an excellent take-off. Sadly I brought no radio gear with me though, so was unable to take advantage of the site.
Labels:
lincoln
24 Mar 2013
Clear air forward scatter optical kit
The schematics below are of the RX and TX used in the recent "over the horizon" NLOS 481THz optical tests. As you can see, not too much complexity involved considering the useful science that results. All parts are inexpensive and readily available. Nothing critical apart from the PIN photodiode and the 280000mcd red LED which I got from Hong Kong via eBay. 100mm optics used at the TX and RX ends.
The 481THz receiver |
The 481THz beacon transmitter |
23 Mar 2013
Reverse beacon Network
7MHz QRP RBN spots this evening |
Labels:
rbn,
reverse beacon network
More books on eBay
A couple more books have been listed on eBay this afternoon which may be of interest to readers. They are the RSGB's latest VHF/UHF handbook and the Backscatter Technical Compendium with articles from Backscatter (UK Microwave Group) from 2004-2008. The auction ends next weekend.
I have an almost complete set of SPRATs from the early 1980s to today that may be listed soon: as I have the CD, the paper copies are taking up shelf space. Paper copies are easier to thumb through though, so I may decide to keep these. We'll see.
There are a few other books and some baby clothes too if you, or your XYL, are interested. My aim is to declutter the shack as much as I can before the house move. The other books include some on disability related subjects, psychology and the Galapagos Islands (the latter is a very nice BBC book).
Last week's auction was very successful with all the books (and the fireplace surround!) finding new homes.
eBay is quite fun in small doses: I don't like to do this all the time - too much trouble packaging and labelling things and making the trip to the post office to send them off, but from time to time it is fun, especially watching the last minute rushes!
More books, including a few more obscure non radio related ones, will be listed next month.
I have an almost complete set of SPRATs from the early 1980s to today that may be listed soon: as I have the CD, the paper copies are taking up shelf space. Paper copies are easier to thumb through though, so I may decide to keep these. We'll see.
There are a few other books and some baby clothes too if you, or your XYL, are interested. My aim is to declutter the shack as much as I can before the house move. The other books include some on disability related subjects, psychology and the Galapagos Islands (the latter is a very nice BBC book).
Last week's auction was very successful with all the books (and the fireplace surround!) finding new homes.
eBay is quite fun in small doses: I don't like to do this all the time - too much trouble packaging and labelling things and making the trip to the post office to send them off, but from time to time it is fun, especially watching the last minute rushes!
More books, including a few more obscure non radio related ones, will be listed next month.
More K1 fun
http://www.elecraft.com |
22 Mar 2013
FT817ND prices at Waters and Stanton
Looking on the Waters and Stanton website I notice they have increased the price of the FT817ND by around £30 to £565.95, despite the Yen exchange rate improving (in W&S's favour) by around 10%. I was rather hoping that the revised price might be nearer £499 i.e. downwards.
Would W&S care to comment on why the price has gone up suddenly by so much?
Perhaps there is a very good reason. To help everyone understand what I mean, see the BBC currency graph for the Yen over the last 12 months.
Looks to me like the UK pound buys a LOT more yen than in the summer of last year. Come on W&S, tell us what's going on.
UPDATE: I am being told the price in the USA has risen by $50 recently so maybe the rise is being driven by Yaesu? If so then they could be in trouble: falling handheld sales as a result of Chinese competition may be forcing them to squeeze for profits elsewhere? The slippery slope to niche markets and ...?
Would W&S care to comment on why the price has gone up suddenly by so much?
Perhaps there is a very good reason. To help everyone understand what I mean, see the BBC currency graph for the Yen over the last 12 months.
http://www.bbc.co.uk/news/business/ |
UPDATE: I am being told the price in the USA has risen by $50 recently so maybe the rise is being driven by Yaesu? If so then they could be in trouble: falling handheld sales as a result of Chinese competition may be forcing them to squeeze for profits elsewhere? The slippery slope to niche markets and ...?
Labels:
waters and stanton
What happened to Wireless World?
When I was younger, and that was a LONG time ago back in the 1960s, Wireless World was an amazing monthly magazine: it was around 10mm thick and packed with articles and information. My old girlfriend's dad had a WW collection going back to the late 1940s and I used the excuse of looking through these to go to see her during summer holidays. Not that much reading took place on those visits!
My question was what happened to Wireless World? It was still around a few years ago in a rather sad state about one third as thick as the editions I recall in the 1960s and earlier. I presumed it has died a death as I'd not seen copies for some time in the shops. A little more searching shows that Wireless World is now known as Electronics World and this April marks the 100th anniversary of its foundation as Wireless World back in 1913. Can't say I've noticed copies in W.H.Smith.
My question was what happened to Wireless World? It was still around a few years ago in a rather sad state about one third as thick as the editions I recall in the 1960s and earlier. I presumed it has died a death as I'd not seen copies for some time in the shops. A little more searching shows that Wireless World is now known as Electronics World and this April marks the 100th anniversary of its foundation as Wireless World back in 1913. Can't say I've noticed copies in W.H.Smith.
Labels:
electronics world,
wireless world
21 Mar 2013
Phasing direct conversion receivers
What I think is quite an old paper turned up in my browsing today: http://www.norcalqrp.org/files/austinnc2030presentation.pdf . In it, Dan Tayloe N7VE describes how a direct conversion design with phasing to cancel out the unwanted sideband can be a truly excellent receiver. I have never tried this approach myself, but think it would be worth it for, for example, a WSPR receiver where the phase accuracy has only to be maintained over a 200Hz audio bandwidth. Over such a small audio bandwidth a very simple phase shift network would work.The same applies on TX where a very simple final frequency phasing TX could produce quite good sideband suppression with very few parts.
Labels:
direct conversion,
phasing
The current G3XBM (operating) shack
G3XBM QRP shack in a bedroom corner |
The maximum power I can run currently is around 7W from the K1 and about 12W out on 472kHz from the transverter (about 5-10mW ERP) and 30W from the 136kHz transverter (about 50uW ERP). I have no great desire to run much more power. The FT817 is only used at 2.5W or less.
20 Mar 2013
RaspberryPi WSPR TX
This means little to my software incapable brain, but may be of interest to some readers: a Raspberry Pi mini-computer used as a basic 10mW WSPR TX up to 250MHz with a suitable low pass filter on the output. I know my old colleague Bob G3WKW has done something similar. I am impressed.
See https://github.com/threeme3/WsprryPi
See https://github.com/threeme3/WsprryPi
KW Vanguard
Alan's KW Vanguard |
A reminder to Alan and others that most 10m AM activity is between 29 - 29.1MHz. In recent months there has been plenty of activity on AM when the band has been open across the Atlantic. Great fun.
Labels:
kw Vanguard
QSOs with the Elecraft K1
As I am considering selling my Elecraft K1 rig to fund some other purchases, I decided to fire it up this afternoon to see that all was well. It turned out to be a very pleasant QRP session with 8 QSOs in 8 countries in the log at 5W on 40m and 20m in a casual hour or so of operating. In addition, there is a page full of reverse beacon spots for the CQ calls that didn't get answered. With the Par 10/20/40 end-fed antenna it doesn't need much to match the antenna: in fact without the auto-ATU it should match well on 40 and 20m, although with the internal auto-ATU I can also match this on 30 and 15m.
I still have mixed feelings about parting with this rig: it doesn't get used much so really would be better with someone who would make full use of it. On the other hand, when I use it I get good results and plenty of QSOs. We'll see if it goes or stays in the coming days. It will be on eBay if being sold, but not until I've carefully thought about it.
I still have mixed feelings about parting with this rig: it doesn't get used much so really would be better with someone who would make full use of it. On the other hand, when I use it I get good results and plenty of QSOs. We'll see if it goes or stays in the coming days. It will be on eBay if being sold, but not until I've carefully thought about it.
19 Mar 2013
Low cost netbooks and ReadyBoost
http://content.hwigroup.net/images/products/xl/132431/asus_eee_pc_x101ch_black.jpg |
At the moment www.amazon.uk has a very good deal (£173) on the little 10 inch Asus X101CH netbook. Reviews are mixed, but overall this may fit the bill for a small second PC that can be used to run simple (Windows software) tasks without much multi-tasking. It should also be able to run WSPR or Spectran as long as nothing much else is required at the same time. There is a lot of bloatware supplied which probably slows it down for most novice users. With ReadyBoost installed on an SD card I think the 1GB of RAM should be less of an issue.
My question is have readers of this blog any experience of using ReadyBoost to speed up sluggish netbooks? Also, have any readers actually got an Asus X101CH and, if so, any views on its suitability for (single task) use with WSPR, Spectran or similar?
Labels:
asus,
readyboost,
x101ch
18 Mar 2013
8.5km "over the horizon" on 481THz tonight
This evening I ventured further afield with the optical kit to see if I could copy my QRSS3 beacon signal in the village of Stow-cum-Quy which is 8.5km from home . This is non line-of-sight and nearly twice as far as my previous tests last week.
Success! After quite careful searching both horizontally and vertically, the signal was copied and recorded at around 14dB S/N (at best) pointing just above the horizon. After searching for a stronger signal, the sky became increasingly "murky" and I was unable to find the signal again, so I came back home.
This range is about the practical limit: aiming is very difficult and I find it is hard to get back to the same direction/elevation if I move anything. I need a tripod that is far more stable with some sort of degrees marking (both horizontally and vertically) so that I can go back to the best settings with confidence. At the moment it is a bit "suck it and see" to find the best aim and nearly impossible to get back to those settings easily if the tripod gets knocked.
This was clear air scattering as there was hardly a cloud in the sky. I have still to try cloud-bounce with real low level clouds.
To see the signal play this recording through Spectran with it set to 572Hz in 0.34Hz bandwidth. QRSS3 signal will be clearly visible.
There is a chance that I may try a much longer 27km NLOS path before too long. Looking at the map, this should be a possibility but I may need another 6-10dB from a Phlatlight LED and a MUCH more stable tripod!
Path covered this evening NLOS |
1W LED TX in 100mm optics, SFH213 detector in 100mm optics |
This was clear air scattering as there was hardly a cloud in the sky. I have still to try cloud-bounce with real low level clouds.
To see the signal play this recording through Spectran with it set to 572Hz in 0.34Hz bandwidth. QRSS3 signal will be clearly visible.
There is a chance that I may try a much longer 27km NLOS path before too long. Looking at the map, this should be a possibility but I may need another 6-10dB from a Phlatlight LED and a MUCH more stable tripod!
17 Mar 2013
My books on eBay
This week I have 8 items for sale on eBay including a few radio books. I am trying to de-clutter ahead of our house move in a few months time. It is proving harder than I thought to get rid of things and in fact I am still collecting more things than I am disposing of!
The radio books are QRP Basics by George Dobbs. This is an essential guide to low powered radio operating. As I have the newer edition, this first edition version is for sale. Highly recommended book.
The next is LF Today by Mike Dennison G3XDV which is the first version of the guide to LF operating especially on 136kHz, although invaluable for 472kHz too. I used this version extensively when first setting up to TX on 136kHz.
The next is The Comprehensive Radio Valve Guide which is a Babani series book listing every radio valve since 1956. As a semiconductor man I hardly ever looked at it.
Another book is the 6 Metre Handbook, a guide to the magic band by Don Field G3XTT. This book is really aimed at 6m DXers and I was a bit disappointed that it didn't say more about using the band for simple local communications.
There are also a few other good books listed and a mock marble fire surround which my local builder tells me should sell for over £100.
You can find all 8 items for sale via http://myworld.ebay.co.uk/rlapthorn .
Get bidding if you are interested as they are sure to sell.
The radio books are QRP Basics by George Dobbs. This is an essential guide to low powered radio operating. As I have the newer edition, this first edition version is for sale. Highly recommended book.
The next is LF Today by Mike Dennison G3XDV which is the first version of the guide to LF operating especially on 136kHz, although invaluable for 472kHz too. I used this version extensively when first setting up to TX on 136kHz.
The next is The Comprehensive Radio Valve Guide which is a Babani series book listing every radio valve since 1956. As a semiconductor man I hardly ever looked at it.
Another book is the 6 Metre Handbook, a guide to the magic band by Don Field G3XTT. This book is really aimed at 6m DXers and I was a bit disappointed that it didn't say more about using the band for simple local communications.
There are also a few other good books listed and a mock marble fire surround which my local builder tells me should sell for over £100.
You can find all 8 items for sale via http://myworld.ebay.co.uk/rlapthorn .
Get bidding if you are interested as they are sure to sell.
Labels:
ebay
16 Mar 2013
100 subscribers - thank you
Just noticed that the number of people who subscribe to this blog has now reached 100 for the first time. Many people just drop in from other links, but it is good to see that so many people actually subscribe. I try to post things that interest me, and I hope interest you too, here. Please let me know if the blog can be improved in any way.
Things (such as designs) that are of longer term use are added to my main website www.g3xbm.co.uk so check there too if you've not visited it.
Things (such as designs) that are of longer term use are added to my main website www.g3xbm.co.uk so check there too if you've not visited it.
Labels:
100,
g3xbm,
rss,
subscribers,
website
Android and iPod WSPR
WSPR on the iPod Touch 4g |
If anyone knows if this has/is being done please let me know. I am aware of WSPR watch but this is NOT a WSPR terminal, just a neat reporting app. The picture shows what WSPR might look like on such a device - I wish!
I wrote to Joe Taylor to find out if the creator of WSPR knew of any attempts. This was his reply:
"Hi Roger,
No such effort has been attempted, to my knowledge.
-- Joe, K1JT"
A solar peak in late 2013 and another in 2015?
Some experts at NASA are predicting some strange behaviour in the next few years with the possibility of a twin peak for cycle 24 but with one peak being this year and the other on 2015. A similar twin peak occurred in cycle 14 in the early 1900s. See http://www.arrl.org/news/solar-cycle-24-may-have-double-peaks-says-nasa-solar-physicist. If this happens we may have (half) decent conditions for several years yet in this current solar cycle.
Conditions in this peak really are very different from the massive peaks in the middle and late 20th century when worldwide DX was workable with ease on the higher HF bands and even 6m. OK, it is still possible to work all over the world but, believe me, it WAS a lot easier back then.
Conditions in this peak really are very different from the massive peaks in the middle and late 20th century when worldwide DX was workable with ease on the higher HF bands and even 6m. OK, it is still possible to work all over the world but, believe me, it WAS a lot easier back then.
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