World Wide Web Edition |
June 2001 |
Welcome to the June edition.
Better late than never, I suppose! My apologies for the lateness of
this issue, and for the non-appearance of the last two BeechLogs.
With all the rain we had in the first half of the year, I had no
excuse for not getting down to writing all this, but such a lot has
happened to me that I was distracted by other things.
The usual trips to Germany and France were uneventful, and various
happenings at work meant I have been more than occupied with, well, work.
Anyway, here we are again. Not much radio in this issue, so it's about
time some of you put pen to paper (or fingertips to keyboard) and wrote me
something for the next issue.
After the last issue, someone asked "What does Marks missus look like?"
So here you are - apologies for missing it out last time.
Roger G0HZK, Editor |
More travels
Although I have seen a little of the world while travelling on business, I
never get to see very much. So I decided this year was the time for a short
holiday away from the children. Most of them are old enough to look after
themselves, so I decided to take my wife for a few days in
Florence.
It was possible to get a packaged holiday there, although there were a few
snags. Probably the biggest was the need to fly from Gatwick at six o'clock
in the morning. Some of you may enjoy that sort of thing, and indeed I
usually take the first flight from Heathrow when I go abroad on business.
However why fly from Gatwick when there's a big airport ten minutes drive
away? So I decided to book the flight via the internet.
Well, this process seemed simple, but was not quite so. I tried different
travel companies, and found that they all gave different flights. So gave a
different answer each time I filled in the online form. But in the end I
chose a flight just after lunchtime. Since there are no direct flights from Heathrow to
Florence airport, I was able to make a decision about connecting flights. The
package tours generally flew Gatwick to Rome, then a five hour wait for a
flight to Pisa, then a train to Florence. But I booked flights from Heathrow
to Milan, and a 1 hour wait before a flight to Florence.
This should have worked out fine, but of course there were a few hitches!
Since I was going in May, the summer timetables were not available when I
booked. So eventually the lunchtime start slipped to about four in the
afternoon, which should have been OK.
When I actually got to Heathrow, there was no sign of the plane. There was
some talk of Air Traffic Controllers in Italy, and eventually the plane
arrived an hour late. After boarding, we sat in this Alitalia plane for
another hour, while 'bad weather over the channel' prevented take off. Anyway
we eventually got airborne, and arrived in Milan at about 9pm.
Ha, guess what? We missed the connecting flight, and the flight after that
(the last one of the day). But Alitalia were ready with a minibus to take us
to Florence. Well after they found the other passengers missing baggage,
another hour. So, at about 10pm we were on our way again, driven by a
non-English speaking driver.
This would have been an interesting drive in the daylight, as the route was
quite scenic, over mountains and through valleys. The motorways in the north
generally had tolls, athough the charge was made electronically to a portable
'thing' that the driver showed us. I don't know whether radio was involved,
but who cares, I'm on holiday.
At about 2am we arrive in Florence. It seems that the driver has never been
here, as it involves a lot of stopping to ask the way. The airport was
closed, so he took us to the station. This was fine, about 5 minutes walk to
the hotel, but we took a taxi anyway. Our hotel was a four star business one,
very nice too. They were expecting us, I had phoned them from Milan, the
wonders of GSM. So at least one of my bookings had worked out better than
expected.
Florence is a curious place, a mixture like I suppose all ancient cities are.
The placed seemed to be swarming in police, who came in two forms. Both
armed, even women on point duty had a holster on their belts. We even saw
them running through the streets with riot shields and rifles, although we
didn't see anything to justify the heavy prescence.
While we were there, the Mille Miglia ran through the streets. I wondered
what was going on, when a crowd of tourists separated and a couple of vintage
Bentleys came roaring through. This went on for a few hours, I've never seen
so many Ferraris before. In Britain, if such a thing were contemplated,the
crowds would be kept well back, but here in Italy, the public, traffic and
racing cars all mixed together. It was quite incongruous to see a pair of
E-Types charging down the street with one of those strange three-wheeled vans
that seem popular in Europe.
As I said, this was a short holiday and finished all too soon. Paying 150
thousand Lira for our last meal, I wondered how the Italians would cope with
the Euro, due to replace many currencies in six months time.
The flights back were uneventful and on time. The plane out of Florence was a
tiddler, no more seats than a bus, four jets which seemed so close I could
almost touch them. The airbus back from Milan flew over the Alps, the snow
glistening in the evening sunshine.
As I write this stuff, it's exactly one month later, and I'm still missing
the place.
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New toys
Again apologies for the late appearance of BeechLog. It's been a
busy start to the year, both at work and at home, and radio has not played a
big part. In fact I have spent less time on the radio than for ages. Most of
my activity is from the car, but in March, I was offered a new mobile QTH, so
it took a while to get a radio installed.
The 'new' car is about four years younger than the old one, and much bigger.
There is a nice cubby hole where my radio sits, but getting the power to it
was another problem. In the end I tapped off the electric mirror switch -
which is fused at 15 amps (I think it feeds the electric windows too). Of
course this modern 1992 car has no gutter, so currently a mag mount holds the
aerial, but it seems to work OK.
I have actually made a few QSOs from home, even on HF! The obligatory D68C,
whose superb operaters showed up almost every other DXpedition. A few
stations on six metres, although my neighbour is complaining about the beam
which is currently mounted on the shed, about 15 feet off the ground.
One delay to writing this magazine has been a breakdown in my computer. I
write this on a Psion, which decided to go wrong a while ago.
The screen went
all funny, and the serial port would only work when the Psion was in the
fridge. This meant I had difficulty getting the data off the machine, and in
the end lost some files, of course the back up wasn't quite up to date! So
today I invested in a compact flash (CF) card. The general idea is that I can
back up to the card every time I write anything new - I must write a program
to do this.
I had a look around Slough for the card, as I prefer to buy from local
dealers than mail order or the web. The best bargains are in Jessops, the
photography shop. My 16 meg card cost less than £20, they were £48 in Dixons!
Since most PCs don't have build in card readers, there are a couple of
options. A PC card (PCMCIA) adaptor cost £8, and USB card readers about £25.
So if you have a laptop, the former is the best option. You can get a PC Card
board to fit in desktop PCs, I've got a couple of these boards, but I've
never seen them for sale anywhere.
Anyway my Psion is back now, and the CF card works fine.
These computers are a pain. My wifes laptop died during the week. This
worried me a bit, I had visions of £££s passing before my eyes. I diagnosed a
failed hard disk, and took it in to work for a spot of lunchtime
dissassembly. Luckily it proved easier than I thought, the hard drive became
accessible after removing just one screw - it was under a cover next to the
battery. So off to the IT department at work - do you have a 2.5 inch hard
drive I could borrow?
"We have a few old laptops, let's have a look. How about this broken
Toshiba?". Under a cover sat a 3 gig hard drive, which I removed and fitted
into Marys Toshiba. I turned on the power, and 5 seconds later Windows
appeared on the screen. Bingo! The IT manager scrapped the machine, no-one
wants a 75 meg laptop with a broken screen, so my wife was in luck.
Of course she lost all her data, although I backed up all her work a few
months ago and put it on CDs (now where's that CD?). The Toshiba web site
provided up-to-date bios and drivers, so by the end of the day I had Windows
98 working and she was reading her email. Phew. My wallet escaped.
My own PC is still evolving. I found a PC World 'Managers special' 20 gig
hard drive which is now fitted. I've been migrating the machine to Windows
2000 for the last six months, as it seems a lot more stable than any other MS
offering. Yes, I suppose I should have considered a *nix OS, but they still
have to evolve a bit to become useful. I did investigate *nix software
available on the web, but much of it is still in the dark ages. It may be OK,
but seems to require the user to read the mind of the programmer when it
comes to installing the stuff. I looked at DOS and Win32 emulators - these
seemed to have parts scattered around the web, and I think the instructions
for locating all the parts were partly written in Aramaic, and mostly
non-existant, like some of the ftp sites that supposedly hold the software. I
suppose if I grow my hair and beard it may become clearer...
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How active are you?
Anyone who has even looked at the uk.radio.amateur usenet newsgroup could be forgiven for
thinking it had nothing to do with radio. Much of the chat is about scoring points over the
"brain dead Cbers", i.e. those without a G3 callsign, or whether the imminent end of Morse
testing will signal the end of real radio. But sometimes there are interesting points raised,
a couple of recent ones being the
RA report about radio amateurs willing to pay £81 for the
annual licence, and a "survey" on how active the group participants are.
Someone suggested that you could define an "active" radio amateur by the number of QSOs logged.
It was suggested that if you logged 50 QSOs a month, then you were active. This led to the usual
bragging, "I made 200 QSOs at the weekend, all CW" and the like. It made me think about my own
situation, and looking in my log I certainly didn't meet that criteria. Some recent years show
perhaps a year per page, although I always seem to start off with a flurry of log entries, which
tails away by the 2nd January.
This year has perhaps been more "active" than most, with QSOs on 21, 24, 28, 50, 144 and 432 megs.
But the log never tells a true story, as most of my "activity" has been mobile, and of course I
don't have to log all that. I suppose someone of the newsgroup will decide that mobile QSOs do
not count, they are generally deprecated anyway, unless perhaps the QSO is on top band. However
you will notice from the list above that there were some contacts on HF bands, I don't think I
made any at all last year! VHF probably doesn't count, as it represents the activity of a "brain
dead CBer", and since I took the multiple choice RAE and an RSGB Morse test, I suppose that's what
I am.
I started off this year with good intentions, and I haven't given up yet. I have been rearranging
the aerials at home, and have mounted a pole at the end of the garden. This met with my neighbours
displeasure when I stuck my six metre beam on it, although that was only temporary. The real
intention is to mount a vertical there, and also use it as the "far" end of a wire aerial.
Probably the latter - the ten metre vertical will probably go back up on my wall. I have had a dual
band 50/28 Mhz mobile whip on this pole recently, and while it works well on six, the ten metre
performance is not up to the CB aerial, even with a couple of radials.
In any case, if I am going to make any use of my new FT100, I had better do something about HF aerials.
I ought to be using ten metres now, as the band is very active this summer, so maybe this weekend I
should get my finger out. Provided it's not raining, or too hot, it should take only an hour or so
to get the half-wave up.
Anyway, back to the topic of how "active" we are. I suppose that besides getting bored with radio,
our modern lifestyle doesn't fit in so well. Back in the era of G3's, it was probably considered
OK for a man to leave all the usual household activities to his wife. I suppose the man would pop
off down to the shack at 6.30 pm, and stay there, fortified by the "little woman" bringing him tea
and food at appropriate intervals. It would be interesting to see how this works today. Are the
really active 200 CW QSO's per weekend men married at all? Do they have children at home? How do
they find time to watch the 150 satellite TV channels that is essential these days?
If I am to become more active on amateur radio this year, how much time is considered acceptable
for the modern husband? To get up to the 50 QSO/month level, how long should I spend on each
contact? Is there activity on any band in the 5.30 to 6.30 am slot when I am normally in bed?
If I get rid of this computer, will I find more time for radio. Something to think about.
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Sporadic E?
This year I have found myself involved in discussing Sporadic E propagation
on the Internet and elsewhere. This is a phenomena that is generally
misunderstood, and gives rise to various explanations that seem unlikely to
me.
As we all know, the ionosphere is usually subdivided into several layers,
commonly the D, E and F layers. The F layer is usually split into 2
sub-layers, F1 and F2. The E layer can also be divided, although this is not
so common. These layers have historical divisions, and roughly indicate areas
containing different quantities of free electrons (ionisation). They are also
divided by density, the D layer having the highest density, being closest to
the earth. You can see a diagram on the
Appleton Laboratory
web page, http://www.rcru.rf.ac.uk/ionospheric/structure.htm
These layers can reflect or refract radio waves. The D layer reflects some
radio waves during the daytime, particularly at low frequencies. Higher
frequencies are able to pass through this layer, and reflect or refract from
an E or F layer. These effects are most noticeable during the daytime, when
radiation from the sun activates them. At night, the lower levels become less
ionised, so that low frequencies can pass through and reflect off higher
layers.
Looking through many web sites, I have found many descriptions of what
Sporadic E is and does. Alas these descriptions vary depending on which band
the writer is most interested in. For example, some six metre operators talk
of it being a major player in long distance communications. Today I have read
a US expert talk of EU to US contacts via "triple hop Sporadic E".
This I find very hard to believe. Most sources quote Sporadic E propagation
requiring "small clouds of intense ionisation", which I can accept, although
some talk of "large clouds...". "Multiple hop" propagation requires the
signal to be reflected from one cloud to another, some 1500km away, and
triple hop presumably requires 3 reflections. I find this hard to swallow.
Since all three layers can reflect/refract 50MHz signals, why do they not
consider that their signal has reflected by a higher layer? The likelihood of
3 clouds being in the right place seems unlikely, and some writers have
remarked that it is strange that signals have not been heard from other
locations in the signal path. Furthermore, each cloud needs to be angled in
such a way that signals are not returned at the angle received, but exactly
at the right low angle to catch the next cloud.
10 metre operators talk of Sporadic E "short skip". This can of course
happen, and does, but quite often signal can be heard from a variety of
locations during these events, suggesting to me that the E layer has become
ionised sufficiently in general, rather than just a small cloud.
On two metres there is generally less confusion. Path lengths are usually in
the range of 1000 to 2000 kilometres, which is easily explained by a
reflection off a cloud at the traditional E layer height. Two metre operators
will verify the sudden starting and ending of propagation, which is easily
explained by a the movement of small cloud of ionisation. Of course, you do
find paths of over 3000 km, but these are not usually described as double
hop. These may be explained by the cloud being higher than usual, or
assistance by aurora or tropo ducting. These long paths are often over water,
e.g. UK to Canaries or Israel, or even the near 4000 km of the Hungary to
Canaries QSO.
In the UK, Sporadic E is usually characterised by (i) sudden starting and
ending of propagation, (ii) unpredictable path, (iii) it happens regardless
of the state of the solar cycle, (iv) the time of day - usually after lunch,
(v) the time of year, especially June.
Of course it is very difficult to discover exactly what the process is. If
something doesn't fit the traditional models, we have to guess. My view is
that we should take with a pinch of salt any explanations regarding multiple
hops. Bear in mind that these ionospheric layers are loosely and
traditionally defined, and unless you have ionospheric echo sounders all
along the propagation path, there is no easy way of figuring what is
reflecting, and where.
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Beechlog is Copyright Burnham Beeches Radio Club 2001.
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