For the first time in more than a week I ran the WSPR beacon through the night. Best DX reports were from GM4SLV, GM0UDL and Lubos OK2BVG at 1232kms. Lubos sent me this picture of his fine shack. Notice the lovely LF/MF loading coil on the left hand side and the LF receiving loop in the corner. Lubos has a very nice collection of equipment. He has now managed to receive me on several different occasions on 500kHz.
The Dutch magazine CQ-PA has quite a large article on 500kHz operation this month. I was very pleased to see my little IRF510 based transverter circuit and my small vertical antenna were shown. Amateurs in the Netherlands have recently been granted access to this band.
"The National Institute of Standards and Technology (NIST) and partners from industry and academia have designed and tested experimental antennas that are highly efficient and yet a fraction of the size of standard antenna systems with comparable properties. .....NIST engineers are working with scientists from the University of Arizona (Tucson) and Boeing Research & Technology (Seattle, Wash.) to design antennas incorporating metamaterials—materials engineered with novel, often microscopic, structures to produce unusual properties. The new antennas radiate as much as 95 percent of an input radio signal and yet defy normal design parameters."
EA3GHS and EA3FXF have produced a single IRF510 FET based version of his Mosquito transceiver using a PC as the back end of a software defined radio (SDR). In essence, the FET is used as a regenerative or direct conversion receiver - I think the two are indestinguishable in a single stage RX - with audio coupled to the sound card via a mains transformer which steps up the impedance. The IRF510 is capable of up to about 7W in this application. Coupled with an SDR back-end and this is SOME simple transceiver, especially if the crystal is VXOed.
Web software defined receivers (SDRs) are becoming quite common now. They allow you to eavesdrop on a number of different HF bands and tune around for stations as if you're located at the distant location. The best place to find a list of these receivers is at http://www.websdr.org/ . I have used the one in Twente, Holland to see if my QRP 80m signal got to The Netherlands (it did) and to check activity on bands like 500kHz. Sometimes these SDRs are located in places where the background noise levels are very low too.
Apple has finally revealed its new killer product - the iPad. My son has an iPhone and is very pleased with it. I doubt I will be persuaded to buy either. I have been tempted with the Apple iPod Touch which is a very desirable product.
After a break of a couple of days, I'm back on 500kHz WSPR again this evening with my 1mW ERP. The reports are still coming in from far and wide (G, GM, PA and LA so far), although no super-DX from central Europe yet this evening.
This morning I worked M0DRK using my tiny 60mW XBM80-2 transceiver I designed last week. It uses just 13 parts plus the crystal, earpiece and optional frequency offset switch. My report for Derek was 599 and he gave me 599+40dB. Derek is in the same village. Also monitoring was G4LHI in Huntingdon 32kms away and he reported my signal was as strong as Derek who was running 5W. In fact 60mW is only going to be about 3 S points down on 5W. I also heard GM3JUD when listening on the XBM80-2 on 3.560, but was unable to raise him.
Yesterday I found this wonderful link which is a montage of 40 different old shortwave interval signals from almost 50 years ago. Get a coffee, sit back and listen. Imagine you are listening on your one valve radio in your bedroom in 1964. It brings back such happy memories that I am almost tearful with nostalgia.
G3ZJO has a QRSS3 beacon sending in FSK built in Altoids tins and running QRPp power. This is is a screenshot (from Spectran) of his signal this afternoon. I have superimposed his callsign, which is clearly visible on the upper line. The first dash of the G in his call is missing in my capture.
Want to try something really simple? I am now waiting to have a QSO on 80m CW using my XBM80-2 transceiver that I put together in the week. Pout is 60mW. The only switching between TX and RX is by the morse key. Additional offset can be had with the switch in series with the crystal. Skeds with local stations are being arranged.
"I simulated the antenna based on your description (with MMANA) and the current through the vertical wire seems to be quite constant. So the tophat works well and the effective height will be more or less the physical height. The simulation gives a radiation resistance of 0.074 Ohm, so with 0.12 A a radiated power just over 1mW EMRP (1.75mW ERP). In the real world it will be some dB's less (as Jim stated recently), probably something like 0,5 to 1mW ERP. Very impressive that it covers over 1200km."
International QRP Collection is a new book bringing together articles from magazines around the world on QRP (low power) radio. There are articles on commercial equipment, homebrew ideas, test equipment and operating on bands from 160m to microwaves plus much more. A friend who is not too familiar with QRP thinks it is a good introduction, but I must admit I was disappointed: the collection seems disjointed and, in my view, a better set of articles could have been put together. As an example, the intriguing transceiver on the cover does not appear in the articles inside! Overall, I'd give this one 6 out of 10. The book is available from the RSGB. 
The Pixie and Micro80 are well known simple transceivers for any HF bands. I've built both in the past and they do work well considering their lack of complexity. The main limitation is the receiver which uses the TX PA as a simple mixer. For those wanting more information on the Pixie and its derivatives check out The Pixie Files which is a collection of articles from SPRAT.
Lubos OK2BVG is receiving me well again tonight on 500kHz WSPR. In the last hour two reports received via the database.
Hello Roger, LF!A little later the signal was even stronger:
This moment is just now:
2136 -7 0.2 0.503874 0 G4JNT IO90 23
2142 -29 -0.5 0.503910 1 G3XBM JO02
Congratulation!
Lubos, OK2BVG, JN88KS
Dave Ingram, K4TWJ died this morning having lost his battle to overcome a massive heart attack on New Year's Eve. He wrote a regular column in CQ Magazine and was well known in the QRP community. RIP Dave.
Hello Roger!
I didn´t see your QRPP signal, when we tried WSPR some days ago. So... I packed my receiver + computer to a car and I moved them on my portable QTH outside of town today morning. I have got EWE aerial for 500kHz there. I started whole set on frequency 502.400kHz. It will be receiving continuously some days and nights. I have got Internet line from my cottage to my home hamshack, so I am able to see what is written in WSPR window there. It will be interesting test, I think.
73! Lubos, OK2BVG, JN88KS
"Plessey Semiconductors, one of the most renowned names in the UK’s semiconductor history, has been relaunched as a chip business operating from the original Plessey CMOS fab at Roborough in Plymouth.Electronics Weekly is available online and is well worth checking.
Plessey Semiconductors has been created out of Plus Semi, a company set up to acquire the manufacturing facilities of two former Plessey fabs in Swindon and Roborough."
This is the schematic of a little experimental 80m CW transceiver. It puts out about 60mW and is only moderately sensitive, although I have not managed to accurately measure it yet. Offset between RX and TX is about 400Hz but more can be obtained by closing S1. It should be used with a low pass filter really.
This is a picture of me in my shack. I had just completed some homebrewing and was having an SSB QSO. See next post for details of the homebrew experimental transceiver I had been working on.
The Twente University online SDR in The Netherlands has now got a 500kHz receiver. It works well and SM6BHZ's SSB beacon was coming through very well a few moments ago.
Interorbital Systems of California have introduced a kit to allow you to build your own satellite! The price of the Tubesat kit ($8000) includes the cost of a launch into space as well.
This evening, early, the transatlantic WSPR stations are coming through well into Europe. So far I've only seen WE2XGR/6, running 100W, appear on the screen on 511.5kHz, which is above the UK allocation. This is a new transatlantic station for me. The signal is varying in QSB with around 8 minutes between peaks of signal.
Last night again produced some decent DX reports with the 1mW ERP 500kHz station, but still I'm 10kms short of the magic 1000kms target. Best was DL4RAJ at 990kms who spotted be many times during the night. A new reporter this morning was M0GNM in IO91 - thanks for the report.
VE7SL has a neat little LF/MF TX circuit on his website which is suitable for QRP 136 or 500kHz operation. Its original application was for 160-190kHz part 15 "lowfer" beacons in the USA. I used the same PA arrangement in my first 500kHz transverter and I can confirm it is very reliable and robust.
21 unique stations reported hearing me on 500kHz WSPR last night, but still the 1000kms target has not been reached - so close but so elusive. On RX, I was able to copy LA3EQ, PA0A and SM6BHZ as well as the local Gs, but no transatlantics.
Just look at this WSPR screen from 500kHz at 2330z this evening. There are G, PA, LA and SM signals coming through pretty well. 500kHz is now getting quite busy at night and it's harder to find a clear spot in the 200Hz WSPR sub-band!
Last night I ran the WSPR beacon again overnight hoping to beat my magic 1000kms barrier using the 1mW ERP station. Unfortunately there were no reports quite that far (990kms was the best), but it was an excellent night with lots of DX reports. DX is of course relative: G4JNT was copied in Alaska and several stations were heard across the Atlantic. Still for my modest power I was well pleased.
Dom Baines M1KTA has just completed his version of the Flea transceiver for 40m and it looks a very neat job. Dom describes this on his blog and it is well worth a look. He gets 1.3W out from a 2N3866 PA. I look forward to working him very soon.
This evening, Andrey RN3AGC sent me an intriguing screenshot taken from his PC in Moscow 2433kms away from here. It shows a very weak trace on the screen at the frequency which only G3XBM was operating last night. It is just possible this was my 1mW ERP signal. If so, it was too weak for the WSPR software to decode. You have to look very hard to discern the trace. Hello Roger,
Probably? :)
Yesterday only you on this frequency worked.
73 Andrey
"Scientists have uncovered what appears to be a further dramatic increase in the leakage of methane gas that is seeping from the Arctic seabed. Methane is about 20 times more potent than CO2 in trapping solar heat. The findings come from measurements of carbon fluxes around the north of Russia, led by Igor Semiletov from the University of Alaska at Fairbanks."See http://newsvote.bbc.co.uk/1/hi/sci/tech/8437703.stm
For a change I put my WSPR beacon on 40m this afternoon and set the output power to 100mW. Within minutes there were reports coming in and some are very good. For example, -9dB S/N from a German station suggesting another 20dB attenuation (i.e. 1mW out) and the signal might still be copied. A few minutes later and there was a log from an LA 1500kms away. Incidentally, several CQs on 40m CW with 1W failed to get a response an hour earlier! I'm now trying 100mW on 30m.
Conditions on 500kHz have been good again this evening. F6CNI near Paris was receiving me at an incredible +2 dB S/N on WSPR. I cannot understand how my signals can be this strong so far away! Also tonight, a new reporter, DL2SEA heard me 442kms away in JO30 square. The screenshot shows my signal as he received it.
