Tuesday, March 31, 2009

Taking the heat on global warming

Fellow QRP enthusiast Larry W2LJ has been taking some flak for expressing doubt that humans are entirely to blame for global warming. I expressed my own opinion some time ago in an article "The Great Global Warming Hoax". I am in total agreement with former British Chancellor of the Exchequer Nigel Lawson, who argues that current policies regarding climate change are completely misguided in his book "An Appeal to Reason: A Cool Look at Global Warming". Lawson shows that there are many reasons to doubt current theories, but that even if they turn out to be true, the cost of the measures that are proposed to prevent climate change would be much greater than the cost of adapting to the consequences of it. Given that we now face a global recession, isn't it time we all took a long hard look at this "inconvenient truth"?

I'm not going to waste time arguing about alleged scientific facts with people who haven't even read Lawson's book - so don't even try. However I believe that the general public of the western world have been taken for mugs, while politicians have jumped on the climate change bandwagon in a quest for greater glory. It's hardly surprising that two of the most prominent political campaigners on this issue have been a failed presidential candidate, Al Gore, and that starry eyed idealist former British PM Tony Blair, the quality of whose judgement can be seen by the fact that he believed there were weapons of mass destruction in Iraq.

I doubt if so many people would be so keen on "saving the planet" if they realised just what it would cost in terms of their personal lifestyles. Ordinary people in places like India and China are certainly not signing up for this. They don't want to forego their chance to own cars, TVs, fridges and travel the world on their holidays like we've been doing for decades. And how much of those luxuries are we prepared to give up so that they can enjoy a better life without adding to global carbon emissions? I thought not.

People have been hoodwinked into believing that the sacrifices they will have to make will amount to little more than switching off the TV at night instead of leaving it on standby, and changing to energy efficient light bulbs. And they are conned into paying a premium for "green" versions of products. Environmentally friendly has become a great sales gimmick that goes down well with affluent people who can carry on consuming while at the same time thinking that they are helping to save the planet.

In the EU it will apparently be illegal to use filament lamps after 2010. Now I don't like paying more for my electricity than the next man, so I use low energy bulbs where I can already. But there are some applications where filament lamps are the only solution. For example, I like "mood" lighting, and you can't use low energy lamps with dimmer switches. How will this law be enforced. Will "green" police peer through your windows at night and issue you with fines if they see illegal light bulbs glowing?

As radio amateurs, the implications of having the government decide what is a responsible use of energy is worrying. If using a filament lamp is a crime, what about running a 1KW linear amplifier whose sole purpose is in the pursuit of a non-essential hobby? As a QRP enthusiast, it would not be a disaster for me if it was decreed that henceforth, all amateur radio equipment must be powered by renewable energy sources. But really, I think the measures that would be needed to reduce global carbon emissions would have an unacceptable impact on everyone's freedom and standard of living. Given that the justification for this is some suspect predictions based on the theory du jour, which could well be discredited once new evidence comes to light (as so often happens with scientific theories) I think it's time more people stood up and said "Enough of this nonsense."

Friday, March 27, 2009

Taming the Cub

I thought I'd have another look at my 20m MFJ Cub this afternoon to see if I could reduce the drift a bit more. I thought I'd try to find out which component was causing the temperature sensitivity by blowing warm air at it through a tube made of a rolled up bit of paper. I could make the VFO quickly drift off frequency by blowing at Q2, the mixer/oscillator chip. But I could do exactly the same by directing the air at the slug tuned inductor. In fact, as far as I could determine, any temperature increase anywhere made the VFO drift off frequency. This reminded me of the time I attempted to use the Cub out of doors. The frequency drifted up and down as the sun went in and out of the clouds that are a permanent feature of an English summer day!

W1HUE's article suggests that it is possible to temperature compensate the Cub by choosing the right combination of different types of capacitor. But it seems to be a lot harder to buy different types of capacitor here in the UK than it is in the USA. You have to pretty much take what you can get, and all of the smaller value capacitors available from the suppliers that will sell to hobbyists have a zero temperature coefficient, which is not what is needed.

Possibly a "huff and puff" stabiliser circuit would be the answer. Unfortunately I'm not an electronics designer so coming up with a design for one would be beyond me. Cumbria Designs has a kit for a board called the X-Lock VFO Stabilizer which might do the trick, but I can't find anything on their website that would suggest how it could be incorporated. I'd have to lose the internal battery to make room for it, but if it could solve the problem then it would be worth it.

Since the Cub starts to drift after you start to transmit, even when it has reached a stable operating point on receive, it's clear that the small amount of heat radiated by the PA transistor heatsink is causing the problem. My latest idea is to try to prevent the heat from getting to the VFO components by making a screen of thin card and fitting it across the Cub circuit board so the PA is in one compartment and the VFO in another. This hasn't eliminated the drift but it seems to have reduced it a bit further, which is at least a step in the right direction.

Thursday, March 26, 2009

QRP is amazing

Some time ago I built an MFJ Cub 20m transceiver. It was fun to build, and has a very nice receiver with true single sideband selectivity using a crystal filter. I added a built-in rechargeable battery pack using ten Toshiba AAAL NiMH cells I got from a RadCom advertiser, making a very small self-contained transceiver, just add an earpiece, key and antenna. Unfortunately the VFO drifted so much I was too embarrassed to use it on the air, so it gathered dust on a shelf for several years.

The other day I decided to try to cure the drift by replacing the two polystyrene capacitors supplied by MFJ, along the lines suggested in an article by Larry East, W1HUE. First I tried using a pair of ordinary disc ceramic capacitors, but these made the drift far worse, though in the opposite direction. So I ordered some NP0 miniature ceramic capacitors. These show no change in value when warmed or cooled according to my capacitance meter. I installed them, and the drift is appreciably reduced, though the transceiver still does drift slowly LF when first switched on. I haven't left it on to see if it eventually stabilizes. But I suspect that whatever causes the drift it is not those two capacitors.

I was realigning the transceiver with the antenna connected, and heard Evgeny, UA1TET from near Novogorod calling CQ. I replied and he came back to my first call. He gave my signal 539 and complimented me on my signal with 1 watt. OK, European Russia is not exactly DX, but to make the contact with 1 watt to a dipole zigzagged in the attic is still a thrill. QRP is just amazing!

Friday, March 20, 2009

Digital voice: the way forward?

In the April 2009 issue of RadCom, technical editor Giles Read asks if digital ham radio is the way forward. He argues that the emergence of digital voice modes offering better voice quality than FM, better resistance to noise and interference, and the ability to be routed transparently from radio to radio using networks like D-Star, is the future of the hobby. My reaction is to hold up my hands in horror and say: "I hope not!"

My adverse reaction is not luddism. It's just that I believe these increasingly complex technologies, whilst interesting to those few amateurs with the skills to understand them and develop them, reduce most of us to the role of mere end-users. And what is the satisfaction in that? Using a D-Star network to talk to someone half way round the world is no more interesting or challenging than making a mobile phone call.

When I first became interested in radio as a young lad, DX locations really seemed exotic. Most took weeks to reach by ship, communication by letter took months, phone calls if possible at all were prohibitively expensive. To contact such places by radio was a real achievement, something only radio amateurs could do.

Today the world is a much smaller place. There is hardly anywhere on the planet you can't just pick up the phone and talk to. You can have email conversations with people in the remotest locations. There is nothing special any more in simply being able to communicate. Ham radio needs to add something extra to hold people's interest.

There are few activities that give more of a thrill than contacting someone thousands of miles distant using a radio you built yourself. And that is one of the few things that only amateur radio allows you to do. Radios that can receive - and even transmit - traditional modes like SSB, AM, FM and CW can be built by anybody. Digital modes will always require a 'black box'. And I believe the more complex technology you need between the microphone at one end and the loudspeaker at the other, the more the magic of radio communication is lost and the harder it is for ordinary amateurs to make their own equipment.

Reliable, error corrected communication under any conditions is not what ham radio is meant to be about. I predict that amateurs will still be building and communicating with radios using the same modes we have used for years, long after the store-bought digital D-Star radios have lost their novelty and are gathering dust on a shelf.

Thursday, March 19, 2009

K3 updated

My package from Elecraft finally arrived yesterday. As well as the KXV transverter interface I had ordered parts for some of the hardware mods to update my early K3 (serial number 222) to the current spec. I don't like modifying radio gear, especially modern stuff that uses SMT parts, but one of the mods was supposed to reduce distortion on the line output that I use to receive data modes, and I had seen signs of that on the waterfall traces, so I was keen to do that mod if nothing else.

One of the earliest modifications that Elecraft made to the K3 concerned the hardware AGC (HAGC), to improve the receiver dynamic range with close-spaced signals. That mod involved removing an SMT part, although Elecraft provides conventional replacements that can be added in parallel to other SMT parts for those who wish to keep the need to touch SMT parts to a minimum.

I was reluctant to touch SMT parts on my K3 at all, but the instructions for performing the mod suggested using two soldering irons simultaneously, one at each end of the part to be removed. I still have a miniature Antex soldering iron bought over 40 years ago, so I dug it out of a box in the garage. With that and my solder station I applied heat to both sides and the part came away with ease.

Flushed with my success, I was almost tempted to go the whole hog and install the SMT replacement components that Elecraft provided. But in the end I decided not to push my luck and used the leaded components. I can't honestly say I have noticed any difference having done the HAGC mod, so if you are reading this and haven't done it yet, I wouldn't worry.

Tuesday, March 17, 2009

Parcel Farce lives up to its name

The mystery of the delivery that never happened has finally been resolved, though not without a certain amount of personal embarrassment.

I was concerned that the package hadn't been delivered because Elecraft had incorrectly addressed the parcel, so I sent them an email asking them to confirm the shipping details. I received a reply that contained an address with the house number and street name missing, an incorrect phone number and an obsolete email address that had one letter missing so it wouldn't have worked even had it still been available. Faced with evidence of such apparent incompetence, I replied with a rather blunt email telling them to sort out their mistakes, and followed it up with a rant on the Elecraft reflector.

This morning I received an email from Elecraft saying that the full address had been on the shipping label, but had for some reason failed to copy correctly into the email. Just as I sent my reply, a correctly addressed letter arrived in the post from Parcel Force stating that they were holding a package at their depot pending payment of the customs fees (VAT.) So the address apparently had been correct, and they had not attempted to deliver the package at all.

From one of the more polite replies to my reflector rant I learned that Parcel Force records that it attempted delivery on the USPS tracking site when it sends the letter asking for payment of the tax. I didn't know this, so I believed that they had attempted to deliver it to the wrong address. Elecraft had then confirmed my belief by informing me (incorrectly) that they had addressed the package in such a way that Parcel Force had been unable to deliver it at all, and were probably just about to send it back to the USA marked 'undeliverable.'

It has all been a bit embarrassing in hindsight. At the time, though, being given to believe that Elecraft had made four separate errors in the shipping details for my order seemed to justify a rant about falling standards of service.

I don't know why it takes so long and costs so much to order things from Elecraft. You can buy things from eBay sellers in Hong Kong and your purchase arrives in half the time the postage is half the amount, and very often it even escapes the attention of the tax collectors.

Monday, March 16, 2009

The meaning of 72

Someone on QRZ.com asked today what "72" meant at the end of a CW contact. He thought they had sent "73" and he had simply mis-copied. But after the third time he realised that they were really sending "72" and he wanted to find out what it meant.

As a QRP enthusiast I soon realised that other QRP ops would send "72" instead of "73", so I guessed that it just meant "73 (best wishes) from a QRPer."

The principle of QRP is one of doing more with less. But Nick, KD5RFT spotted that it actually requires slightly more power to send "72" than "72" - one more dash and one less dot - and suggested that perhaps it would be more in the spirit of QRP to send "74" instead!

Transverter interface lost

More than a fortnight ago I ordered a KXV3 transverter interface from Elecraft in the USA. As it had not arrived near the end of last week I obtained the USPS tracking number from Elecraft Sales. When I copied this into the USPS Track & Confirm site I found that it had been stuck in UK Customs for 4 days. It was released on Friday morning, so I hoped to receive the package today.

Nothing came, so I entered the tracking number again. This time the site reported: "Attempted Delivery Abroad, March 16, 2009, 12:28 pm, GREAT BRITAIN". But my wife and I had both been here all the time and no-one had attempted to deliver a package at any time.

A few years ago you could order something from the USA and it would be here in a few days, often as quickly as when ordering from a UK supplier. But buying from the USA is becoming more and more of a hassle. I think it's time Elecraft thought about setting up a UK or European office.

Friday, March 13, 2009

K3 memory hassles

I'd like to report that following the fixing of the transverter bugs, I am now completely happy with my Elecraft K3. But unfortunately there are still some major annoyances that need attention.

The K3 provides pretty good support for using transverters, including an offset value that can be used to compensate for any inaccuracy in the transverter local oscillator so that the frequency displayed is accurate. Unfortunately, when you set an offset, the frequency displayed when any memory is recalled has this amount added to it. So if I set an offset of 200Hz, my 2m calling channel memory now loads the frequency 145.500.200. Elecraft says that this will be fixed, but in the meantime you should set the offset before storing frequencies in the memories. Now they tell me!

Setting up memories using the front panel controls is a hassle in any radio. But just about every modern radio with a computer interface supports memory management software. Bill Coleman, N2BC, has written a great K3 management tool called K3_EZ, so I downloaded that in order to edit my K3 memories. Unfortunately - and through no fault of Bill's - K3_EZ cannot be used to manage the K3's internal memories. The memory feature of K3_EZ only allows frequencies to be saved and restored from the computer. The only way to read or set the K3 internal memories using software would be to cycle through them, one at a time, by emulating front panel key presses, and that would take an inordinately long time. What's needed is direct access to the memories using software, and there isn't any.

Another example of how the K3 ergonomics haven't been fully thought through also involves memories. When you use the VFO control to cycle through stored memories you can't listen on each memory channel as it is selected. You can't use the VFO as a channel selector on FM. You must select a memory and then press the M>V button to load it into the radio and receive it.

There is a "channel hopping" feature that lets you scan a selection of memories. This at least allows you to scan FM channels and stop on one when a signal is detected. But only the receive frequency is loaded into the radio so if you stop the scan, other stored settings such as repeater shift or DCS tone are not loaded. If you call the station heard when you stopped the scan, the K3 will use whatever settings were last selected. You have to press M>V to fully load the memory contents, and of course it's easy to forget to do this.

It's such a shame that the K3 is operationally so inconvenient to use on FM because the receiver is very sensitive and the sharp crystal filter improves SNR and rejects adjacent channel interference much better than the second IF ceramic filters employed in most amateur multimode transceivers.

Thursday, March 12, 2009

Wainwrights are on the air

Well, the cat is out of the bag. The web project that I have been working on for the last couple of weeks is Wainwrights On The Air (WOTA). The news was broken yesterday by Tim, G4VXE, in his blog.

Wainwrights On The Air is an award scheme in which radio amateurs try to make contacts with (or to make contacts from) each one of the 214 mountains in the English Lake District that were described by A. Wainwright in his famous Pictorial Guides to the Lakeland Fells. It's a bit like Summits On The Air (SOTA) - indeed, that's where I got the idea from - but with simpler rules and counting only the mountains in the most beautiful area of England.

Three weeks ago I had no idea I was going to do this. I had resolved that I was going to get out walking in the local Lake District hills, and take a radio with me for a bit of extra interest. I looked into SOTA as a way to provide more focus to the radio activity and hopefully get me more contacts, and was disappointed to find that only a few of the well known Lakeland mountains actually count for SOTA. The decision as to what makes a mountain for SOTA is a rule based on "prominence", with the result that many attractive hills are omitted, while several mundane ones that happen to be a long way from others are included. As a SOTA activator I would have ended up driving past many mountains that would have given me wonderful walks, just to get to the ones that counted.

I think the 214 Wainwright fells present an attractive challenge to "collect", either as a "chaser" (someone who works the hill-top portable stations from home) or as an "activator" (someone who climbs the hill with a rucksack full of gear.) Although difficult, it is realistically possible to work and/or activate all 214 tops. WOTA will obviously be less popular with those who live in parts of the country far from the north west. But it is also intended to be an example to others to set up hilltop challenges in their own areas. In fact, I hear that another group of people is putting together a more general adventure radio scheme as I write. Watch this space.

For my own part, I hope that WOTA will result in many more contacts when I take my radio to the top of the local hills. I hope that it will provide a boost to the radio activity in this not very populated part of England, where even the repeaters are silent most of the time. WOTA might even provide a tourism boost as people from further afield find out about this wonderful area and come here for a week or two to do some summit activations themselves.

If you think you might be interested in taking part in Wainwrights On The Air, check out the website. The programme starts on the first day of Spring, 21st March.

K3 transverter bugs fixed

I am pleased to report that the problems I reported when using the Elecraft K3 with a 2m transverter requiring a high power IF input have been fixed. I received a beta test firmware version 3.00 in my mail this morning from Wayne at Elecraft. The K3 will now remember that my transverter needs 4W of drive out of the antenna socket, instead of a few milliwatts out of the non-existent KXV3 transverter interface. And it does not prevent me from transmitting when I set the receiver to 145.700MHz or above.

Fans of Elecraft will point out that no other radio manufacturers would provide a fix for a reported issue within two weeks, and they may well be right. But I still think it would have been better if the bugs had not existed in the first place.

Radio rage

I don't know if there is something about ham radio that causes people to develop a blinkered view of the world in which their opinion is always right, or whether radio makes them angry and intolerant. A couple of years ago I ran a blog on this site and tried to stir up participation by making some deliberately controversial comments. I expected disagreements - that was the point. What I did not expect was the number of people who could not express their views as a reasoned argument, but who resorted to personal abuse instead. In the end I deleted the entire blog.

These days I try to avoid controversy. But it still often surprises me that some innocent comment or intended-to-be-helpful post produces a strong negative response. On the Elecraft email reflector this morning someone asked whether it was really worth upgrading from a K2 to a K3. This was my response:

I have a K2, and went for the K3 because of its much improved support for digimodes (which were really an afterthought on the K2) and FM (which isn't catered for at all.) The fact that the currency exchange rates were favourable at the time I ordered it, and the credit crunch hadn't happened, had a bearing on it too.

I think the K2 and K3 are like apples and oranges. The K2 is a more basic radio with an emphasis on portability (small size, light weight, low current consumption, facility for internal battery.) Plus it has the unique benefit that you get to build it. The K3 is clearly designed to be more of a high end desktop radio for those who want the ultimate in receiver performance. And even if you'd prefer to build it, you only get to assemble it.

If you aren't sure you need the K3 then in my opinion you probably don't. I don't chase DX, I only contest casually, and I don't really need a high end radio. If Elecraft had brought out a K2 Mk II with 1Hz VFO resolution and dedicated input/outputs for digi modes it would probably have done the job for me, even without FM. So your decision will surely depend on whether there are things you want to do that the K2 can't do.

I received a nice reply from Gary KI4GGX who complimented me that "my post was one of the more thoughtful of the bunch." But I received another, from a ham who shall remain nameless, that consisted simply of the word "NO!" plus his name and call. He had put it in something like a 72pt font to make sure I understood. That, to me, is not an argument.

When I express my opinions, on the web or anywhere else, I expect that some people will disagree. But if everyone who disagreed with me sent me email to say "You're wrong" my inbox would be full. I always like to hear the other point of view, if it is politely expressed. Sometimes I may even learn something. But if you can't be bothered to explain why you don't agree with me, don't bother writing at all, because I'm not counting votes.

Wednesday, March 04, 2009

Stop the twittering

It seems as if everyone is joining Twitter at the moment. This morning I had an email from a work acquaintance inviting me to join. And now I see that QRZ.com is on Twitter. What's the point of it?

I got as far as the home page, which says that "Twitter is a service for friends, family, and co–workers to communicate and stay connected through the exchange of quick, frequent answers to one simple question: What are you doing?" So it seems to me like just another way to help people be even less productive by interrupting them with pointless questions. I don't want to be disturbed when I'm working on something, or even when I'm on the air, by people wanting to know what I am doing.

There is already a device called a telephone which allows people to keep in touch by the far superior method of speaking. If people I know what to know what I am doing, they can phone up. If I would like to receive a greater number of enquiries as to my current activity I can also leave a radio on a local repeater and let people know I am monitoring it.

If I want to tell the world what I am doing, I can do so at a time of my choosing using my website or this blog. In other words, I think enough ways to contact me exist already. Nobody needs Twitter, except people who are afraid they might be missing out by not joining the latest fad.

So G4ILO is not on Twitter and has no intention of twittering, now or in the future.

Tuesday, March 03, 2009

Junksale.co.uk's ridiculous restriction

I recently bought a 2m transverter that I found advertised on Junksale.co.uk. I'm not a member of the site, but it can be viewed by non-members, and the seller had put his email address so I didn't need to go through the site to contact him.

However, I wanted to join the site, both to give feedback to the seller and also because it seems like a good site for buying and selling ham radio equipment in the UK. But when I tried to register, I received a message that "your email address has been banned. Contact the webmaster"

Puzzled about how I could have been banned from a site I'd never even heard of until now, I contacted the webmaster. He replied that "the server does not accept free email addresses. Use an ISP email address." Well, I have news for him. I don't have an ISP email address. I use Gmail, like millions of other people. It's far more convenient to use an address you don't have to change whenever you change ISP. Plus, many people use an internet connection shared with other people so, even if an email address comes with the account, it isn't theirs to use. What a ridiculous restriction!

I could, of course, have used my work email address. In fact, I tried registering using that, and then changing it to my Gmail address afterwards, but I got the "your email address has been banned" message again. It's not convenient for me to use my work address for hobby matters, so that's no use.

I could, of course, set up an email address under my web hosting account for the g4ilo.com domain. But I don't want one. Gmail provides a far superior webmail client and is better at dealing with spam than anything else I have come across. And I long ago gave up using rubbish like Outlook Express, Microsoft Outlook and Thunderbird. Why on earth go to all the bother of downloading email to a personal computer so you have to use that PC to access it, when you can access Gmail from literally anywhere? Personal computer email clients are so 1990's.

So that's that. I'm not joing to jump through hoops and set up a special email address just because some webmaster has a thing about free email addresses. I'm afraid Junksale.co.uk has ended up in the trash can.

Monday, March 02, 2009

CQ to accept eQSLs for awards

My copy of the March CQ Magazine has only just arrived, so this will not be news to many people, but I was pleased to read that CQ will now accept eQSLs for its various awards. At last, someone is taking a practical commonsense attitude towards contact confirmation!

It has long been time that the costly, time-consuming and wasteful business of postal QSLing was laid to rest. Most radio amateurs now have internet access. Of those who don't, I expect many are in less affluent parts of the world and find the cost of printing and posting QSLs painfully expensive.

The argument that eQSLs are easier to forge has always been false, and never more so than since the advent of high resolution scanners, colour laser printers and PhotoShop. An eQSL is automatically verified, since only the station making the contact being claimed for can create it on the system. There is no way for someone who needs a particular confirmation for an award to fake an entry.

I'm glad to see that this aspect of the hobby is finally moving into the electronic age of the 21st century.

Banner Exchange Down

I have just noticed that the Amateur Radio Banner Exchange site (www.cq-cq.com) is down. There are no banners on my site and I'm getting a "Suspended" page from Hostgator when I try to access it. The same thing has happened to the Amateur Radio World Ring (g6dpp.com).

I do hope it is only a temporary glitch. G4ILO's Shack has been in the top 10 sites of the banner exchange for a long time, and gets a lot of traffic through it. The World Ring has been a nice way to find other ham radio sites as well.

Does anyone know what's up with these sites?

Keeping the spammers out

If you do anything on the web that allows people to post comments, such as a guest book or a forum, then the biggest headache is keeping out the vermin who add unwanted contributions linking to sites selling pharmaceuticals and other wares. As radio amateurs there are ways at our disposal to obstruct such unwanted comments. For example, asking a question like "What band is 14.100MHz in?" or "What is the Q code for 'low power'?" would defeat most non-hams. But this isn't often used, probably because most people use standard packages and don't know how to hack the code to add such a question.

I'm currently working on a new ham radio website which I can't say anything about yet (hence the infrequency of blog postings at the moment.) This site will require people to register in order to access the interactive pages, and I wanted to not only keep the spammers out, but also ensure that amateurs register using their callsigns.

Thanks to phant0m and nrg_alpha over at PHP Freaks Forums, I now have a nice little PHP function that checks whether the supplied argument looks like a valid callsign.
// function to check if argument is in format of a valid callsign
function valid_call($callsign){
return preg_match('=^\d?[a-z]{1,2}\d{1,4}[a-z]{1,3}$=i', $callsign);
(Note that I did not require the function to accept prefixes like F/G4ILO or G4ILO/P.)

You still have to figure out how to call it from your forum software, guest book script or whatever, but hopefully some will find it useful.