Back on 137kHz TX

QRSS and CW beacon TX for 137.685 kHz

Today I went into the shack with the intention of making a new transverter for 137kHz based on my recent design for 472kHz.

Instead, I ended up building a new CW, QRSS3 and QRSS30 8W beacon transmitter using an IRF640 PA device. This evening and overnight the beacon will run QRSS3 on approximately 137.685kHz and I have requested reports and screenshots.

The antenna being used is my 20m spaced earth-electrode pair set-up used very successfully on 472kHz last weekend. On 137kHz signals are much weaker than on 472kHz, so I await reports with interest.

The whole unit runs quite cool when housed in a plastic box. Switches on the front of the boxed unit allow up to 7 pre-programmed messages to be beaconed at varying speeds. As normal, I use the K1EL beacon chip for the beacon message generation. The signal source is a 3.579MHz crystal in a divide by 26 circuit implemented in a PIC like device and kindly supplied to me by a French amateur Francis F6HSI a few years ago.

eQSL cards

Brazilian QSL card received via www.eqsl.net

To be honest I'm not very good at QSLing.  In years past I would regularly write out QSL cards and send them out to the bureau and look forward to the next batch of cards. These days I do send out some paper cards, but not that many. Instead I tend to use eQSL cards instead, but I was way behind with reviewing incoming QSLs so this evening I spent an hour or so getting up to date. I rejected a few cards - one for a WSPR "QSO" where what had really happened was an exchange of reports via the WSPRnet database, and the other for a voice-over-internet QSL with a JA station.

Checking my totals I see that I have 55 countries confirmed by eQSL cards. All these will be with 2.5W or less on all modes, mostly SSB on 10m and 6m. Many of my DXCC countries pre-date the eQSL era and I have not been that active in DXing as such in recent years, apart from the occasional contest like CQWW SSB, which I enjoy with QRP.  As you know, I prefer to carry out crazy experiments somewhat on the edge of sanity on strange bands with odd antennas instead!

More IC7100 photos

http://www.universal-radio.com/catalog/hamhf/3071.jpg

Universal Radio staff in the USA had the new IC7100 multi-band multimode transceiver demonstrated to them in early December and they have posted a few informal photos on their website.  At this time there are no indications of price, but my guess is somewhere in the £1400-1800 bracket here in the UK.  A lot of money, but also a lot of radio, including for the first time full 70MHz transceive facilities and, if this floats your boat, D-star built in. It also has a touch screen interface. I'd like to see a QRP version of this although I doubt the price would be much less. The receiver also covers a wide band 30kHz-200MHz and 400-470MHz.

Another earth-electrode station on 472kHz

If you spot G4HJW/1 on the WSPR database on 472kHz this is Bernie who is about 9km from me on his 30m baseline earth-electrode antenna. G4HJW is him on his Marconi by the way. Looking at his unique spots, he is getting reports from all over the place: not as good as his Marconi but reports out to over 900km isn't bad (GM, F, PA, G etc).

Next week, after the snow has gone, we hope to have a 2-way CW QSO on 472kHz using earth-electrode antennas at each end. That should be fun!

An INDOOR loop on 472kHz TX?

Over the last few days I have been receiving quite strong WSPR signals on 472kHz from Richard G4KPX who is in Ely, some 14km north east of me.  Looking on the WSPR database I see he has been copied up to 573km on the band using WSPR. Now, in a email from Richard today he revealed his secret: he is using just 1W RF into an indoor 3m x 2m single turn loop made of 10mm pipe leaning against the wall of his spare bedroom!  The EIRP is at most 100uW and probably a lot less because of the losses with mounting it where he does and the capacitors used to resonate it. This is a pretty amazing set of results.

Richard has been spotted across the Atlantic on 160m using the same indoor antenna and has similar magnetic loop antennas for all HF bands I believe.

So, if you believe you have no space for an MF band TX antenna, and you don't even have a garden to put a couple of earth-electrodes in the ground, you could always follow Richard's example.

Some months ago I believe one of the German 136kHz stations (DF6NM?) tried something similar using a large coax as a big indoor loop on 136kHz and also got some quite decent results. Never say you cannot erect an antenna!  What you need is a bit of ingenuity.

.....and NOT a TS-990 - something better!

Just to put some perspective on things, this is a small CW transmitter that just about anyone could build for a few pounds only and use it to work stations all over the world with a modest dipole antenna or similar. The OXO transmitter was designed by GM3OXX and is a classic design.

http://www.qsl.net/g3pto/OXO.gif

Power from the OXO is around 800mW - 1.5W depending on the band and on the final transistor and its emitter resistor. I have used this design on HF and had hours of fun with it. Long after a rig like the TS-990 would be gathering dust, this little beauty will carry on giving pleasure with each and every contact.

Kenwood TS-990 - UK price

Well my fellow blog readers, I have some good news for you!

The new Kenwood TS-990 is now available to order for Martin Lynch, and I expect many others, for only £6600 with deliveries expected February. I am sure many will buy this fine radio, but as this is about ten times my budget (once every 10 years or so) for a new HF transceiver, I will not be one of them. 

http://www.jayceecoms.com/images/Kenwood-ts990s-1.jpg

472kHz update

With nearly 2 weeks of operation on the new band with very low EIRP levels (varying from typically 5-10mW with 100mW on just one occasion) perhaps it is time to summarise how things have been going. A check of the WSPR database shows almost 70 unique reports across Europe of my signals from just a few km away to 1736km. I have still not managed to be copied by TF3HZ in Iceland at just over 2000km and this is my next target. To achieve this will need me to re-erect and better optimise my Marconi vertical. With some optimisation it should just about be possible achieve 200mW EIRP.

Unique WSPR spots in the last 2 weeks on 472kHz

On CW I have received a report from over 160km away when I was calling CQ. A JT9-1 QSO with G3ZJO at 79km is still my best 2-way QSO, although I believe it should be possible to work much further with this mode (I worked OR7T in Belgium with it on 500kHz).

So, pretty satisfying results so far. This has been helped by the huge number of stations currently monitoring WSPR on the new band - frequently over 40 people at any one time. Right now there are 59 stations monitoring!

On 136kHz the challenge with small antennas and low power is considerably harder on WSPR as there are too few stations monitoring: even if the signal was getting several hundred km, one can only tell if someone is at the far end and reporting it.

Solar activity this month

A quick glance at the solar data over the last week or two will convince anyone that things are looking up. Many believe that a second peak, not that uncommon, is likely soon and that this peak will actually turn out to be the real peak of cycle 24. It is some time since we have seen sunspot numbers as high as this for so many days in a row. In the end, the peak is usually based on smoothed sunspot numbers so it will be very many months into the future before we will know if the recent upsurge has helped to make a new smoothed peak.

I see there is a possibility of M or X class flares in the next two days which could affect propagation, although I think it improbable these will be on a scale likely to knock out power stations and satellites. At some future point, most likely long after all of us are long dead and at a time when the cycles return to huge numbers of sunspots, it will happen though. Of course large solar flares can happen at any time, so you never know.

For more data on the recent solar activity see http://www.solen.info/solar/ .

Albrect AE2990 Albrect12/11/10m Multimode handheld

Albrect AE2990 multimode

On G4ILO's blog I noticed a reference to Julian's Albrecht 10m/12m handheld transceiver. A quick search on the net and I see these on sale via eBay for £159. See eBay item number 181059871622. This is also sold as a Magnum 1012.

Although I have used the FT817 handheld lots of times on 15 and 10m and had some excellent contacts with it using a small base loaded whip (a counterpoise definitely helps), I have no experience of the Albrecht unit, which looks like an oversized VHF handie.

Has anyone here used one seriously for handheld DXing? If so, how did it perform?  The interesting thing is this unit can be programmed for 12m, CB or 10m use by changing some solder pad links under the PTT rubber.

I can imagine that this handheld could provide hours of fun during a summer sporadic-E opening, although I would expect results to be disappointing without a counterpoise if using it handheld with ether the supplied whip or a longer whip.

True handheld DXing can be quite a challenge, but great fun.  Actually being able to move  the handheld around to get the best angle can sometimes really help, especially on signals coming in at odd angles. Some time ago I was going to see how many countries I could work on handheld SSB, although I've not seriously tried this lately. I much enjoy handheld DXing when on holiday in Devon from clifftop sites overlooking the sea as in these locations many dB can be gained by chosing a nice location with a slope towards the sea. One of my best contacts was a YV station on SSB (8000km) from my late mother's back garden.