Crystal Set DX log from 1991

As I clear out my stuff ready for our move, I've discovered my Crystal Set DX Log from 1991, which was 2 sunspot cycle peaks ago. Looking through the entries in the log (all received with a VERY simple shortwave crystal set using a toroid, a germanium diode, a resistor and a crystal earpiece and a longwire antenna about 15-20m long) it is quite astounding how the HF world has changed.

Shortwave Crystal Set DX log - from 1991

For a start, many of the coast radio stations used to transmit in CW on HF and these could often be read due to the cross-modulation from other stations. This was the technique used to detect those shown in the log above.

Also, the shortwave bands were still filled with English language broadcasts. In the few days covered by this log I managed to receive broadcast stations from Cuba, UAE, India and Australia directly (not via relays) as well as plenty of Europeans. Before this date I had no idea that worldwide reception on a crystal set would be possible.

There is no doubt that conditions were very good back in 1991 and I am not so sure that it would be possible to repeat this in 2013, but I would be delighted to hear of success by others with crystal set DXing on HF in more recent times.

I still enjoy crystal sets: they are simple and fun to make yet there is still something unbelievably good about using the electricity from the TXing station to hear them, not my own, especially when the signal comes from very far away.

IC-7100 UK launch July 17th at Martin Lynch

A few hours after I commented on the price in the US of the IC-7100, I had an email from Martin Lynch and Sons announcing the UK launch on July 17th.

There is still no information that I've seen that gives the likely UK price although I doubt one will be in my new shack.

The IC-7100 is bound to cause a lot of excitement as it is one of the first commercial multi-modes to include 4m (70MHz). The press release seems to indicate that D-star will be supported in the standard product i.e. my understanding is this is NOT an optional add-on, but you get it with the basic product you buy.

The pdf leaflet on the IC-7100 is now available.

Weather boots for coax plugs?

I'm looking for what I believe are called "weather boots" to slide over the end of PL259 and BNC coax plugs to help protect them up the mast from water ingress. I guess it is still necessary to add a smear of silicone grease. There are such items for Sky dish F connectors (see eBay item 251296277220) but I have not yet found a source for the common 50 ohm plugs.

Anyone know where such rubber/PVC boots can be obtained please?

2m big wheel antennas on 70cms?

Just wondering if anyone has checked what a horizontally polarised 2m big-wheel antenna looks like (gain, match, directivity, polarisation) on 70cms?

At the new QTH, the most likely antenna on the apex of the bungalow will be a 2m big-wheel (for 2m datamodes, SSB, CW) with a V2000 fitted above it (for 6m Es, 2m and 70cm FM) with suitable spacing between them (>1.3m). It would be useful if the big-wheel behaved well as a half decent horizontal omni on 70cms too so it could be used in UKAC contests.

IC7100 prices

Image at http://www.hamradio.com/images_manuf/H0-011766A.jpg

The new multiband, multimode mobile/base radio from Icom is now available in the USA for $1,824.90 from Ham Radio Outlet store with a 2 year warranty. It is available for $1,664.95 without the extended warranty. See http://www.hamradio.com/detail.cfm?pid=H0-011766.  If importing from the USA don't forget VAT and import duty.

The usual UK price is about the same in pounds as it is in the USA in dollars, so I guess around £1800-1900 is likely to be the going price, although I don't think the UK dealers have them yet.

At the time of writing there are only a couple of reviews of the IC7100 at www.eham.net

Antennas start to come down and wi-fi range tests

Today marked the beginning of the end for amateur radio at the present QTH. We've lived very happily here for 37 years, bringing up our 2 boys and welcoming our 4 grandchildren. Now we are just a few weeks away from our move to the bungalow 300m away up on our local "hill" next to the windmill, the latter currently undergoing a £417k refubishment courtesy of a National Lottery grant. The new home is a nice place and we are looking forward to the move, but it won't be without a few sad moments: closing a chapter in our lives but also opening a new one. The last time we moved, the removal van cost just £11 - it was a LONG time ago, HI.

Today I removed the first part of the antenna system: my 20m spaced earth-electrode wire running in the back garden. Next to come down will be the coax feed from my workshop to the upstairs shack where I operate. The V2000 vertical and the Par 10/20/40 end fed will come down in a few weeks time. I also de-cluttered the bedroom shack to some extent, clearing out all manner of the "I may need this some day" rubbish that fills drawers and cupboards. It is just unbelievable how many SMPSU wall blocks I have that belonged to equipment like routers and scanners long gone. The worst is always the stuff you've kept because, "I may need this one day".  I am trying to be ruthless and give it to a local charity store, recycle centre or the dump if it has not been used, read, looked at for several years. For certain something that goes will be needed next week.

I did a test at the new bungalow tonight on the internet wi-fi coverage: I took my Virgin Media wireless super-hub and set it up (locally, no internet connection) and walked around the new home with my iPod Touch 4g to see how strong the signal was in the shack, bedrooms and garden. Results were promising: I think I may get away without a range extender.

WonderLoop antenna

If you have just bought a copy of the August 2013 copy of Practical Wireless you may have noticed that in the next edition (September) I'm doing a review of the WonderLoop antenna, although the editors managed to give me a new callsign by mistake in the "Coming next month" column on p77, HI.

Confidentiality prevents me saying anything yet until the edition is published, but I much enjoyed carrying out my tests.  I have absolutely no affiliation with the manufacturer or supplier. As a keen blogger I find it hard not to blog about something radio related that I have played with!

The Wonderwand page is at http://www.wonder-wand.co.uk/WonderWand/WW_Homepage.html .

If you are interested in reading my review, please buy the Sept 2013 copy of PW on sale August 8th.

Birdlip in the Cotswolds

The distant Malvern Hills from near Birdlip

There have been no posts for a few days as my wife and I have been away from home staying a couple of nights on the western edge of the Cotswolds at Birdlip. The occasion was a gathering with cousins I'd not seen for around 50 years. The gathering was excellent. We stayed at the Royal George Hotel (3 star rating) which was superbly located right next to the Cotswold Way path with good rooms, large gardens and excellent value meals.  I am please to report that everyone had a great time and got along fine!

This part of the Cotswolds would make an excellent VHF-microwave location with the Cotswold escarpment meaning the ground falls away dramatically towards Wales and the west. I didn't take any radio gear, but will do so if I stay there again. The hotel was a good find.

472kHz in Canada - getting closer

From Joe VO1NA:

Dear Group,
Last week, Industry Canada published its Proposed Revisions to the Canadian Table of Frequency Allocations. It includes the 630m band for the amateur service.  So we wait with much anticipation...
73
Joe VO1NA

VHF/UHF QRP DXing with weak signal digital modes?

When there is a decent contest with some portable stations with decent antennas about, it is surprising how far can be covered with QRP kit on 2m and 70cm. This makes me wonder just what sort of ranges could be covered with QRP and modest antennas on these bands using WSJT digital modes.

Going from SSB to one of the more effective weak signal modes is like gaining another 30dB, i.e. far more that the antenna gain of a big contest station, suggesting that ranges of 200-300km should be ALWAYS possible on 70cms with quite modest QRP stations with small yagis or colinear vertical antennas in flat band conditions.

I am speculating what sort of ranges should be possible under flat conditions (no lifts) with 5W and a small omni or broad beam yagi such as a Moxon or HB9CV.  When I move to the new QTH I think some 70cm skeds are called for with stations out to 300-400km using WSJT modes using 5W or less.