Wednesday, 23 July 2014

Going Seaside Portable

I've tried a number of antennas, some more practical than others, when going seaside portable.

The most convenient by a long shot is the I-AM end-loaded vertical dipole covering 20-6m.  It's just 6m high when deployed.

The proof-of-concept model was a fibreglass pole, timber and wire affair.  It worked very well indeed, working global DX with ease.

So, I've now gathered the parts for a more robust model, made of aluminium tube.

I've got two pieces, each 2.5m long, of 1.25" tube, separated by a timber insulator - a handle off a new floorbrush!  You can use PVC, fibreglass rod and so on, but it's nice to use commonly-available materials like wood.

At the end of each 2.5m vertical tube is a 1/4", 2.5m long tube that is the end load.  It's attached with aluminium 'Stauff' clamps fixed to a 2mm aluminium backing plate.  The plate is held in place with stainless steel 'U' bolts, tightened with wing nuts for ease of operation.

And that's it!  Just connect 300 Ohm twin to the vertical sections, and away you go!   The commercial version of this antenna costs about £240.  This homebrew version, which has lower losses owing to the twin, as opposed to coax feed, comes in at about £60.  Not bad!  Images coming soon...

Tuesday, 22 July 2014

Planning and the RSGB

For several years by now, I've been trying to get things moving to change planning regulations in favour of amateur radio enthusiasts.  I've never believed it would be easy, but certainly possible.

Want an antenna?  This is all you're permitted without planning in the UK.

Just to be very clear, within the UK, the strict legal position, remarkably, is that only a single, small TV and satellite dish is considered de minimis, that is, what you can expect to install on your property without fear of enforcement action.  Unlike the US, we don't even get to put up a flagpole without planning permission, so flagpole antennas are, of course, not a fail-safe backup!

In practice, you may 'get away' with somewhat more than this - it depends on how bored your local curtain-twitchers are of a day, and how overwhelmed by cuts your local planning authority is.  'Get away' with it long enough - for four years without interruption - and anything you care to put up becomes immune from action. 

In the recent past, the RSGB has claimed that, without it as a representative body, amateur radio would be in a much poorer state than it is now.  I'm sure anyone keeping a tab on sliding membership and age profile statistics would raise an eyebrow over that assertion!

In any event, this week, I gave the RSGB another chance to show what it's doing about changing planning laws a little bit in our favour. I wrote to their planning committee (capitals supressed.)

I was suprised to receive a response from non-other than Graham Coomber, who seems to be handling quite a lot of the society's correspondence these days.

In his response, Coomber is very polite.  But, the content is concerning.  Firstly, it seems to try and 'get rid' of the correspondence by exhaustively asserting the position at law in the UK.  It referred me to various planning regulations, all of which I already know plenty about, as my initiating correspondence indicated.

Then the RSGB displays the troubling characteristic that has been evident over the years: a "don't tell me what's what, sonny' attitude.

In response to my assertion that planning regulations within Wales differed from those elsewhere, Coomber's mate on the Planning Committee actually picked up the phone to Cardiff to see whether this was true!  I'm not sure if it was out of annoyance or not knowing what the situation actually is!

I suppose this was a somewhat better response than my first contact with the RSGB, when then-chairman, Len Paget, vented his fury at a simple, polite letter from your truly. Paget sought out a number of emails of members of another, utterly unrelated organisation which had been illustratively mentioned in my letter, and manually issued his musing about my "suitability" as a representative (which, sadly for him, I was not!) of that organisation to eleven people, eight of whom received it.  It landed the RSGB with a serious ticking-off from the ICO, prompting some hurried updating of the RSGB's lax data protection measures.  It even hit the amateur news headlines. 

Coomber, in his own, much more considered response, accepted that there were differences in some guidance, and made a nod to a review of the law in Wales, but that otherwise, the system was the same as elsewhere in the UK.

You could cut Coomber some slack and say that he's right to indicate the planning system in Wales is firmly rooted in the all-UK legislation.  But that misses several key points.

First, in relation to the ongoing review of planning law in Wales, which will see a new law introduced in the near future, Coomber doesn't indicate - and I have never seen - any RSGB input into the consultation on planning law within Wales.  They had a chance to do so, but for all the world appear never to have known it was underway. 

Secondly, if you consider the detail, which I've now pointed out to Coomber, there is considerable scope for planners locally and hyper-locally to apply what are known here are 'Technical Advice Notes' (TANs).  Number 19 is the one regulating telecomms (which disjointedly includes amateur installations.)

Coomber later asserted, in a follow-on letter, that amateur installations are generally classed as residential development.  Yes, but that doesn't negate the advice of TAN19, which is very clear on including amateur installations.  The RSGB seems to think some other form of system operates, which is most odd.  I asked Coomber if the RSGB can in fact accept any view other than its own, even when shown to be wholly or partly in error?

Again, I'm not aware of any input by the RSGB into the formulation of that TAN and, just like the lack of input into the legislation review, we can, as fee-paying members, very legitimately ask why that has been the case?

TANs are not, of themselves, legally binding documents.  They are guidances that planning authorities are expected to take into account when considering an application.  If the RSGB thinks these are just bits of paper that may optionally be taken into account or ignored for having no weight, they ought to think again.

In the field of wind turbine intallations, the relevant TAN is bandied about like a burning-hot potato in Wales, and is taken very seriously indeed by planners.  Like most such guidances, in practice, they are much more like what must be complied with, rather than just a plain guidance.

Then comes the RSGB's failure to comprehend that guidances, which may include non-binding Supplementary Planning Guidances (SPGs) can become legally binding.  This happens when a guidance is used as the basis of stipulating conditions on a planning consent.  If the developer then fails to comply, the matter becomes one of enforcement, where the authority could refuse to issue a final certificate. 

What's the point of all this, you ask?  Well, the response from Cardiff this week to my latest discussions has been simple, expected, but also sensible.  It asks the amateur community to educate and engage with the Royal Town Planning Institute and planning authorities, so they become more aware of our needs.  It's difficult to argue with that line of reasoning, frankly.

Yes, it's a 'get lost, we're busy' answer in the bone.  But it does highlight the blindingly obvious: the RSGB has failed, for a very, very long time, to put forward its case for a better planning environment for hams, and seems simply content to remind us all, when we ask what it's doing, what the status quo looks like. 

So, the RSGB seems to be resigned to the way things are.

The truly sad point for me is that there is still a very strong feeling within the ruling elite of the RSGB that only they know how to run the show.  If someone tries to tell them something, it is almost always returned with a firm sense of 'we're being got at' defensiveness.

So far as my own experience goes, nobody in RSGB HQ has welcomed comments from the wider world, or asked for help in their work.  They really do seem to think nobody else has anything worth contributing.

Sadly, in the case of planning issues, the RSGB is simply regurgitating what the situation is today, whilst doing very little, if anything, for how things could be tomorrow.  I think that tends to be symptomatic of nicely settled-in, middle-aged, middle class white males - a 'you can't change the world on your own' mentality that, if it were to defer to youngsters a bit, it may find very misguided.

Oh, and Coomber continued his defensiveness by stating, as the RSGB always does, that if you use their services for planning applications, you are "more likely" to gain approval than if you don't use the RSGB.

That sounds worth the membership fee, doesn't it?

Except, it's an assertion missing detail.  It's unlikely the RSGB knows whether this claim is actually true on a like-for-like planning application basis.  The RSGB could simply, by chance, have helped those cases that had a better likelihood of being approved from the outset. Because each application is very unique to its own situation, I think the RSGB is obliged to examine much more carefully the evidence for this oft-repeated claim.



 






Monday, 21 July 2014

Ground Bus Bar - Homebrew Style!

Thunderstorms are a rarity on the north west coast of Wales.  Plenty of sea means storm cells never really build up here; it can be many years between what even then are usually short-lived storms.

Ouch!  Image: Wikicommons.

But not this year!  We've had a run of storms running in from the east, where there's more land to heat up the cells.  As a result, the station has been left running for the coax feeds to disconnect them several times already!

So, it's time to invest in lightning protection.  Arrestors are on the way from DXEngineering, not bad at just over $100 for four.  But the copper bus bars are a bit expensive - about $68 for a four-position bar (which inevitably means won't be enough positions, and so more expense for a bigger unit!)

So, out with the lump hammer!  I took a 3/4" copper pipe and hammered it into a flat bar.  I then bent the ends to make some standoff room.  I used enough pipe to give eight arrestor mounting positions in all.



The standoff insulators are also a bit expensive, with PVC-homebrew ones prone to cracking after a while outdoors.  So, I went native and made my own out of slate blocks!  A hacksaw gets through slate fairly easily, but it tends to get clogged with very fine dust (this is used in toothpaste.)  Eventually, I managed two blocks with nice flat sides, and drilled some recessed holes for the bolt and fixing screws.



I can't testify as to slate's suitability for this precise application, although it has been used in the past for similar purposes.  If you live in a place with lots of storms, I'd look into the insulating properties of slate quite carefully first.  At your own risk, as they say!

Whilst it's a little Heath Robinson, it's nevertheless neat enough, and cost me nothing.  The only problem with using slate is that it's greatest strength - the ability to split it easily - is also its most annoying feature in that it tends to split when you don't want it to!  If you do split a block in two, just use some Araldite-type two-part epoxy, and it will be stronger than ever!


Sunday, 20 July 2014

QRM - USB Charger Plug

One of the more interesting articles in this month's RadCom was a piece about QRM arising from the now very common, essentially zero-cost USB chargers packaged with everything from mobile phones to handheld radios, and which can be used interchangeably on many devices.

Handy device, terrible QRM.

I got out a typical charger, which was supplied with a mobile phone, made in China (of course!), and plugged into the house mains to charge a tablet PC.

The results speak for themselves.  Whilst there was no discernible QRM at 20m, from then on up, it was a very different story, with interference so strong as to make any dubbing of the videos to tell you when the USB charger was on, and when it was off, unnecessary.

Apparently, these devices are meant to operate much more quietly, but circuit omissions are now commonplace such that, once more, the HF bands are under threat from these things, flooding as quickly as they can make them, from China.  The threat is even greater thanks to people's laziness and tendency to leave them permanently switched on.

First, 17m band:


12m band (I lost the 15m vid!):


10m band:


6m band:

Friday, 18 July 2014

RadCom - The WW1 Centenary Edition

Ah!  RadCom, RadCom!  The magazine of the society we love to hate, and the sole reason many of us remain members of the RSGB.

Having rifled through the second hand equipment adverts as soon as the thing flopped onto the mat, it was time to settle down to what looked like an interesting piece headlined on the cover "Lest We Forget.  The Role of Radio Amateurs in WW1".  A lovely blue sky and poppies adorn the cover.



Turning to the article as thunderstorms brought an end to radio play, I found myself scratching my head - and not because of a sweaty evening!  The article simply doesn't cover 'the role of radio amateurs in WW1' at all!  It simply gives a few early operators' names, their calls, and a bit on what they did before and after the war.  A jolly little story here and there of the authorities confiscating receivers, but nothing about how amateurs became involved and played a part in WW1 radio.

In hindsight, given that amateur radio was banned for most of WW1, the article seemed doomed to failure from the outset.  We don't even get an account of amateur operators fighting at the front, or what they did, regardless of their use or not of radio.  Did they tend to go into technical roles?  Not a word.

The article drifts onto some outreach work conducted by a group somewhere, which I'm sure was very worthwhile and a lot of work.  But it's a really strange tangent to the article topic.


Away from WW1, the GHz section gives some useful tips and directions for those wanting to get involved in microwaves, which is a welcome improvement.  However, I sense an undercurrent of 'Oh God, these lazy newbies, they know nothing and I'd rather be writing about the transverter I built from native metals I dug out the ground myself and smelted into electronic components.  That's real radio'.  Come back to Earth, GHz section.  Assume a newbie knows nothing.  It's always a challenge to educate newcomers, but always rewarding, too.

The usual images of old, white, middle class men adorn many pages.  I think I'm right in saying that I've only seen one less-than-white person feature within RadCom in the past year, and only a very few women, also elderly.  Crisis in radio?  What crisis?

I like the nested loop beam made of common, cheap materials.  This kind of article ought to feature much more often, although like most articles on antenna construction, they've been republished several times in various formats, and you get a real sense of stagnation with them.

Then we have a continuation of the 'how to solder antenna wires in the field' topic, which is getting a bit tired now, to say the least.  This month's doubtful contribution is how to use a cigarette lighter (we all have one of those, of course (?)) to solder.

Hmm.  With a large propane/butane canister that lasts for months costing £3, and a infinitely reusable piezo-ignited burner head about the same, I think I'd rather use that for reliable connections in a force 8 gale than cursing at a puny lighter!  Having told us of the lighter technique, the author admits his thumb got uncomfortably hot (what a surprise!), and so rather negates the whole point of the article!


Elsewhere, a section on QRP and tiny rigs from China, and a thought-provoking piece on wind turbine EMC, make up for the less than glowing articles on the other pages.

So, 'could do better', especially on WW1 radio history!


Tuesday, 8 July 2014

Yaesu FT-450 New Arrival

A famous internet auction site does it again!

Last week, I was pleased to sell my trusty TS50s - for slightly more than I paid three years ago for it - to an aircraft radio engineer who will give it a caring new home. 

The TS50 was great, but not a rig easily amenable to modern digital modes.  I used a TS480 for that.

As luck would have it, a hardly-touched FT450 came up on same famous internet auction site for just £100 more, and with just a single bid placed two hours before the end, I 'won' the unit.  I think most butted-out of bidding because they thought it was an ATU-less unit, whereas it actually had the internal ATU fitted. 

A lovely little rig!
 
It arrived within just a day of posting, and is already in full service on all modes.  It's immediately evident that the FT450 is much more stable than the TS480, which has been my main rig until now.  You can send digimodes all day long on the temperature-compensated Yaesu, and it drifts not a jot.  The TS480, in comparison, drifts away like a mad thing, demanding about $100 for an add-on TXCO that, by many accounts, isn't very stable.

The audio on the Yaesu is very good on external speaker and particularly on headphones, and after some tweaking, matches the excellent output of the TS480.  Audio out, always a major Kenwood strength, seems OK on the Yaesu, but that will take more testing.

As is reported by a few ops, the internal speaker resonates to voice on SSB, which is apparently due to poor mounting of some components.  It's no big deal, and can easily be fixed or overridden with an external speaker, which most of us probably use anyway.

Controls on the Yaesu are much more sensibly laid out than the Kenwood.  The LCD display is informative, bright and large, but the contrast could be better, despite a wide adjustment range. 

So I've been surprised that the TS480, an excellent rig despite its desperately lazy 'S' meter and tendency to drift with temperature, has been ousted within a day as the main station rig!  Instead, it seems destined to be the portable rig, though it was never really well thought-out for that purpose, having awkward-to-access external connections.

Well done Yaesu!  I'll give you more thought the next time I upgrade to a larger rig!

Monday, 23 June 2014

Dry Weather - How's Your Station Ground?

We're undergoing another sunny, dry summer in the UK.  Unsurprisingly, we're all very happy about that!

But there are problems associated with dry weather, and one revealed itself in an unexpected way.

Are your grounding points moist enough?  Image: W8JI

A few weeks ago, I threw together a simple crystal set for the kids. The primary coil uses the station ground, connected by crocodile clip. It worked a treat until, a few days ago, it went completely dead.

Having re-soldered all the connections, it was still dead.

Hmm.  I wondered whether the ground system had dried up in the hot weather.  So, I dumped a copious amount of water in the ground at the earthing point.  Within a few minutes, the crystal set was working again!

So, it pays to keep your station grounding moist in hot weather, especially if you live somewhere like the UK, where we don't expect it to ever be that dry!