28 Feb 2015

40m Pixie - bench test went well

Well, it took a super-human effort on my part as a result of my extreme fatigue (brain bleed issue) but today I bench tested the little 40m Pixie kit I managed to build earlier this week. It is hard to explain just how exhausting this simple task was for me currently. I now need to recover my energy!

On receive a 1uV signal was perfectly readable and I could detect carrier on/off down to at least below 0.5uV. On TX it was putting out about 250mW into a 50 ohm load. On my antenna it was suffering some AM breakthrough, but less than I was expecting. I was using standard Walkman stereo headphones and a rechargeable 12V sealed lead acid battery. On a small 9V battery I'd expect about 100mW RF out, although this was not tried.

Overall, these results exceeded my expectations: it is more sensitive than I was expecting and the breakthrough of AM broadcasters is certainly OK in the day time. This is of course with no casing at all and no ATU. Using the fitted pot and fitted 1N4001 as a varicap it is easy to get the TX frequency and RX frequency to correspond, often an issue with very simple QRP rigs.

Next stage will be some on-air tests, but it most definitely works. Working the locals should certainly be possible. Sked with G6ALB (3km) arranged for 1000z Sunday on 7.023MHz CW.

UPDATE 2120z:  There is a contest in full swing and several Russians and Asiatic Russians copied on the little 40m Pixie. I did not stay on long but there was no apparent BC interference noticeable. So, on a quiet night I should able to use the rig in the evenings. The main issue on RX seems to be the lack of AF filtering, so one has to use "the filter that is between the ears" i.e.the brain.

Amateur Radio Weekly

Yesterday I subscribed to this online newsletter. It is also available every Saturday on www.amateurradio.com

One of the items was about Deutche Welle (German broadcaster) vacating a slot in the 49m band. A group of radio amateurs have obtained permission to use a 10kW commercial station there. This is their website http://www.channel292.de/ . Best of luck to them!

10m USA spots today

KZ8C (6290km) was the first North American to spot my 500mW 10m WSPR today at 1248z. Since then, K9AN (6505km) has also spotted me several times. I think he has a very good RX set-up as he is often copying me on 10m.

I have the feeling there will be a lot of 10m spots today as conditions seem quite good and it is the weekend.

UPDATE 2035z:   The last USA station to spot me today on 10m WSPR was KB9AMG (6300km) at 1922z. Quite a decently long opening today.

9H1US

My little 500mW 10m WSPR beacon has been copied 8 times so far today in Malta by 9H1US (2135km). No great DX , but a first time and new country on 10m WSPR. Some reports have been very strong. F2 or Es?

UPDATE 2050z:  In the end 9H1US spotted me 14 times over the lunchtime period. The last spot was 1336z. This could have been Es, but more probably F2 propagation

Sunspots and 10m - Feb 28th

Sunspot number has risen slightly to 58 today and 10m propagation is set to be "fair". this is a better forecast than recent days.

Already, my 500mW 10m WSPR beacon has been copied in LZ, OH, SV9 and 4X1 this morning, but nothing from further afield, as yet.

UPDATE 1114z:  10m does seem livelier than of late. LZ1OI (2153km) has been spotting my 500mW 10m WSPR very well. This must be an optimum distance for single hop F2 propagation.   I've just been spotted in Malta (9H).

UPDATE 1126z:  First DX outside Europe today as when I was spotted  by PU2UIB (9524km) in Brazil at 1112z today.

UPDATE 1230z:  No North American stations copying my 10m 500mW WSPR beacon, as yet, but the first reports will probably be in the next hour.

27 Feb 2015

New online shop - creative wire artwork

Gifts for the XYL?

From my French daughter-in-law:
Hi there,
I have finally come around to opening my shop on easy. Spread the word.
Hope you like it. 
https://www.etsy.com/uk/shop/SurleWire?ref=hdr_shop_menu

Frog 40m transceiver

This is the Pixie's "big brother". I have mentioned it before in this blog. It has more power than the Pixie and a better RX.  It costs just over £15 with free shipping from Hong Kong. Some suppliers sell it built for this sort of price! This is a real bargain.

I think it uses an NE602, with an attenuator pot in the receiver.

The image is on the eBay page and will be removed immediately if a problem.

See http://www.ebay.co.uk/itm/Frog-Sounds-HAM-Radio-QRP-Kit-Telegraph-CW-Transceiver-Receiver-Radio-Station-V3-/251405614850 .

See also: http://www.ebay.com/bhp/qrp-transceiver for lots of QRP transceiver bargains.

40m Pixie transceiver

Yesterday I found my rechargeable 12V battery and charged it up. I also checked the Pixie I built as a kit for dry joints and shorts. As all looks good, I hope to test this on the air over the weekend or early next week.

There are a couple of locals I'd like to test with initially, although I am expecting to suffer from AM breakthrough mainly from broadcast stations very close to our 40m band. Probably there would be less breakthrough in the daytime? My antenna is short and low on 40m (a Par triband end-fed covering 10m/20m/40m) so any contacts will be good!

I can test it first on a signal generator and then a power meter. If it works, I'd expect a sensitivity of around -100dBm and a power out of around 200mW on 40m. We'll see. Even -80dBm and 100mW would be enough to work locals as long as AM breakthrough is at a manageable level.

Cerebellum brain bleed update

Many of you know I had a cerebellum brain bleed in Sept 2013 and was in hospital for 3.5 months. Slowly I am recovering, but it is taking much longer than I expected.

Amateur radio field experiments and building work are on hold, but I hope to resume these soon as long as my fatigue improves.

The main issue is I get tired quickly,  especially after anything that is physical. Even small things leave me exhausted, quite unlike anything I have known. I still feel drunk when I walk, my speech is poor and drinking thin liquids is not easy. The profound tiredness really gets me down. It would be so good to be able to drink a cup of tea or coffee, or even a glass of water, as I used to.

Most foods are OK now.

All limbs, eyes, ears and intellect are fine. I still feel unwell and not my old self yet. Although recovering slowly, it is taking far too long.

10m USA WSPR spots

At 1314z K9AN (6505km) was the first USA station to spot my 500mW 10m WSPR beacon today. With the lower sunspot number I had some doubt the 10m band would open to the USA today at all.

UPDATE 1400z:    W9HLY (6257km) has spotted me a couple times this lunchtime, but I have the feeling there are few stations spotting me today on 10m WSPR.  OK, it is very early afternoon still.

UPDATE 1655z:   A surprising number of USA stations have spotted my 500mW WSPR beacon this afternoon, despite the relatively low sunspot number. When the next peak occurs it is likely to be a weak affair, but assuming conditions are settled we could still be spanning the Atlantic on 10m at the right time of year. It will be interesting to see how well this path holds up as the sunspot number continues to fall.

UPDATE 1732z:  Still being spotted in the USA

UPDATE 1822z:   K9AN (6505km) is still spotting me.

UPDATE 1830z:   Still plenty of USA and Canadian 10m stations spotting my 500mW WSPR beacon. This is a much better opening than I expected.

UPDATE 1940z:  It looks like the last USA spot was KC1AWS (5408km) at 1850z. Just local G4IKZ since then. I'll probably go QRT shortly on 10m WSPR.

UPDATE 2120z:  I went QRT at 2058z. I am currently not active on any band.  Back after breakfast.