RSGB - Thank You.

Like many hams, this op often has a few gripes with the RSGB.  As a society, it's right the RSGB receives reasonable comment and listens to it.  In the past, that certainly wasn't always the case.

Recently, I have been trying to get a club station set up at my local primary school, which I'm glad to say has embraced the idea with enthusiasm.  Practicalities may get in the way and it may never happen, but at least we'll get a few field days at school events, if nothing else.

Slowly, the RSGB is whetting the appatite of the young.  It - and its members - all need to do much more of this.

So, in pursuit of some support and encouragement from the RSGB, I e-mailed them to ask if they would be kind enough to provide some publicity material.

Sure enough, the response was immediate and enthusiastic.  Some days later, I received a fairly large package of materials, most of which is attractive and useful.  The very uninspiring centenary poster, however, is pretty rubbish!

So, a genuine, sincere and big thanks to those at the RSGB who provided the material so readily.  Keep it up.  Publicity, especially amongst kids and now without the benefit of GB4FUN, is nothing short of essential.  I hope the RSGB remembers and acts upon that more in the future. If it does not, there will be no RSGB.

Amateur Radio Revolution?

Tune up to the macho 20m band and all its manly bravado, and you'll soon hear things like "running 1.2kW into a 5 by 5 stacked 5 element array" or some such idiotic nonsense.

If you have the money and obsessive qualities to turn your hobby into a way of life, that's all fine.

For the rest of us, there's a recession bordering on depression going on, and life is hard.

JT65 (or JT9): the way to easy DX with simple equipment.

Of late, I've really taken to the digimodes.  It's never as satisfying as actually talking to someone, but if offers a nice way to keep on operating when the kids are asleep, and shouting down the mic is out of the question.

So digimodes really ought to be the way in which we attract new entrants into the hobby.  And, boy, do we need them!  The attraction of computers and radios linked together is clear.

But the real point of my ramblings tonight are this: with digimodes able to happily work with signals down to -28 or lower, anyone with the ability to attach a matched wire to a transceiver can now operate global DX on low power.

For example, I've a folded 'pyramid', originally a WSPT test unit, that is no more than 4m high, and takes up the space of a very, very small garden.  It is fed by twin line to a homebrew 4:1 current balun.  It has a fairly high SWR of about 3, but that is of little importance with twin, as matching losses are miniscule.

Whilst is is not the best antenna in the world in terms of absolute signal, it can get a pretty decent signal out.  Attached to JT65 running on a laptop, it's easily capable of getting a signal across the world with plenty of perseverance and informed operating (grey line, long path, etc.)

So, let's not forget in our discussions about which $3000, 7-element beam might be best put on top of a $10,000, 100 foot tower that none of that is, today, necessary to enjoy global DX.

If we got that message out to youngsters, maybe we wouldn't be seeing the logarithmic decline in the number of people participating in the great hobby of amateur radio.

MFJ 941E ATU - Replacing That Pesky SWR Light

Its many years ago now since I bought the MFJ-941E matching unit.  MFJ have a very American style of advertising, and reading one of their leaflets sometimes brings to mind a rather dodgy second-hand car salesman's pitch!  The endless use of excited italics to highlight rather unexciting features is also rather quaint.

But that would be to do MFJ a disservice.  The 941E has matched just about anything I have ever thrown at it.  This afternoon, its SWR panel light gave up, giving me a chance to open it up to fix.

These are the very tidy workings inside my MFJ 941E:

Fair play, that's an honest day's work by MFJ for about £140.

 
You can't really find anything to criticise in there, especially mindful of the price.  The 4:1 balun is absolutely tiny, but I always use my homebrewed transformers just outside the shack with balanced line anyway, and never now use the twin input into the MFJ.

Now, back to the SWR panel meter light.  For some utterly unknown reason, MFJ, at least for a time, produced this transmatch using a small incandescent bulb to light it up.  Inevitably, after a couple of years, it blows.  I decided to replace it with some old white LEDs from a broken 6V torch I had just thrown in the bin.  I hastily recovered it, took out the two LEDs, took an educated guess at the correct voltage and current, and added a couple of 90 Ohm resistors in series to bring the nominal 13.8V DC output from the station PSU down to something that didn't turn the LEDs into little heaters!

Two LEDs from an old 6V torch, plus 180 Ohms added resistance give me a nice new SWR meter light for pennies.

I just glued the little circuit board holding the two LEDs to the outside of the panel meter, at the top, keeping the LEDs clear of any plastic and in free air, just in case of any excess heat production.

It works a treat, and I doubt I will ever again have to change the light source for that SWR meter!

Cool blue LED replaces mellow yellow incandescent glow.

Glass Fibre Antenna Poles - The Windy Files.

Fibreglass (or glass fibre) poles are, to most hams, an essential and manna-from-heaven product.  Lightweight and relatively inexpensive, they allow us to make tall verticals, quad and Moxon support spreaders, and all sorts of things in between.

This article is about making your pole last in strong winds.  For temporary use on a beach or field day, it's likely that you'll get away with just a fence post and some cable ties at the bottom.

My pole can bend dramatically at the top on occasion, but after several years in very strong winds, I think my mounting system works!

But can you use standard fishing poles over extended periods of time in windy situations, where the installation is, essentially, permanent?

The answer is an emphatic 'yes!'  It's also an answer derived from my direct experience over many years, living on an Atlantic storm-swept ridge in north Wales.

The basic installation is a 10m glass fibre pole, with the top two metre sections removed because they are too weak to carry weight.  That leaves you with a roughly 8m pole.  Now, I'm a great user of delta loops, but the story holds for any antenna, such as a vertical dipole or GP, held up at 8m or so.

Attach your pole to a half-round or square fence post.  Drive it a reasonable distance into the ground, but don't overdo it, as in the end, it's not the business end of the set-up.  Those are the guy ropes.  I find it's always necessary to level the pole vertically, then screw in lengths of timber either side parellel to the bottom section.  That stops the pole becoming lop-sided.

Attach your pole to the fence post using at least three high quality, broad cable ties.  The breadth spreads the stress a bit.  I use at least two at the upper and bottom ends of the fence post.  It's an idea to replace these every year or so, as sunlight and weather do weaken even the best ones.

Now comes the most important part - the guy ropes.  There are a number of ready-made guying rings available.  Some are better than others.  Avoid ones that are either thin, made of metal, or both.  That's because thin rings place all the stress of the windload in a small area of the pole, making it more likely to snap at that point.  Metal ones are obviously much harder than fibreglass, so unless padded, will quickly rub a cut into your pole, and early failure will ensue.  Some broad, plastic guy rings look good, but often have holes drilled too close to the edge of the outer ring, so that unless it's really tough nylon or similar, it's likely to be worn away and let your guys loose.  You can machine your own, improved ones, of course.

From experience of the 2012 winter and 2013 autumn, which has already thrown a couple of extreme wind events our way, that a fishing pole tends to snap somewhere near the middle at gusts in excess of 60mph.  The mechanism of failure is a splitting of the upper part of a section, which is where the pole is trying to prevent the section above it from bending excessively.  All things have limits!  I have now tried some very tightly wound weatherproof ducktape around the top of each section of a new pole - just a couple of wraps so that each section can still be retracted into the one below it.  This may give a modicum of added strength, or perhaps prevent very small cracks that develop over time becoming larger ones when the wind really blows.  More time will tell.  Ducktape, incidentally, is very good for repairing broken poles, provided you wrap it tightly.

But I've used only broad, high quality cable ties for the guy rings, which are tightened only lightly, and to which lightweight, UV-resistant guying rope is tied.  Use a separate cable tie for each guy rope, so that if one breaks, the others might not and give your pole some chance of surviving.  In fact, you can use two cable ties per guy rope, for redundancy.

As to the position of the guying rings, there are mathematical formulas to work this out, but usually based on metal and not fibreglass poles.  By experiment and worrying through stormy nights, I've found that attaching the guy ropes to the bottom of the fourth section up (at roughly 4m), works very well.  It stops the base from shifting around, whilst allowing the top 4m, which is thinner, to flex.  In a strong wind of 50-60mph, this bending can be dramatic!

How many guys?  Four is best, but I started with three at about 120 degree spacing, and have stuck with that number, though the third has to be moved sometimes when the wind shifts a lot.  It's not been a problem for me.

There are many types of often quite expensive guying ropes out there, so I won't recommend any as I've used only polypropylene rope and then upgraded to an unknown thinner guying rope that came with an end-fed I once bought.  Both seem to be well-suited to tolerating sunlight and weather in general.  But do check your ropes often, and use secure, self-tightening knots.

So there you go.  Real-world testing of a cheap fibreglass pole on a hill often exposed to hurricane-force winds (and I use the word correctly, not for dramatic effect!)   One other thing to look out for is the quality of your pole.  Inspect your poles as soon as you get them, looking at each section.  If any slivers of fibreglass fall out, send your pole back because it's unlikely to be of acceptable quality and will fail early.

Because it's only fair to tell others about good quality suppliers, I recommend you use Paul's Angling Supplies, who runs a shop on Ebay.  I've never had a bad pole from him, and delivery times are excellent.

Should you ever bring your pole down when set-up like this?  If the wind exceeds about 60mph for a few hours, I'd say it's worth retracting it.  Likewise, if you have a direction where the wind becomes both strong and turbulent, then retract.  Steady, laminar flows of even strong winds are much less damaging than weaker winds that swirl around a lot, buffeting your pole and rapidly shifting the forces acting on it.

Also remember to secure your pole sections.  I use what have turned out to be very high quality hand-operated jubilee (hose clamp) clips from FEP Hydraulics, who let you select just one of each size if you want; others insist on buying boxfulls of them.  For a standard 10m pole reduced to 8m, you need  one with the range 20mm, 17-25mm, 22-30mm, 25-35mm and 25-40mm.  I use strips of silicone rubber under each one, cut from egg-microwaving cups.  This has excellent non-slip properties on a pole, and stops the clip from damaging the fibreglass.

Finally, if you are using a delta loop on your pole, it's always a good idea to cable-tie the wires either side of the top insulator together.  This stops the pole slipping along the wire, rendering it likely to become bent over to one side, which is then difficult to correct and makes your set-up look amateurish.  It also means that, if the pole does break, you just need to slip off the top insulator with the delta still attached to it, stick it on a new pole and presto!  You're back on air in about an hour.

Monthly Moan

Yes folks, it's that time of month when RadCom dropping through the letterbox prompts more moaning from me!

This month (October 2013), we are given the half-yearly financial report.  It doesn't make for very encouraging reading.

Inevitably, the National Radio Centre, a legacy of the RSGB's recent 'difficult period' (which saw allegedly criminal conduct), has to come in for heavy criticism.   Why?  Because just under £20,000 of our membership dues have already gone in the first half of 2013 keeping this utter nonsense going.  I suppose it's reasonable to assume it will cost the same amount over the remaining half of the year, so £40,000 for...what?

Frankly, I'm pissed-off with the RSGB endlessly publishing photos of old, white middle-class men trying to look interested at the NRC.  The harsh reality is that the NRC is a useless lead weight around the RSGB's neck when it is, as a society, simply managing - just - to break even financially.  Men in uniforms and ceremonial chains don't convert into hard cash, therefore it is a waste of time.

The RSGB can go on as much as it likes in positive spin about the ''several" who have taken up radio training and obtained a licence as a direct and sole result of visiting the NRC.  But how many is several?  We're never told, because it's clearly a tiny number.  That makes them very expensive new members indeed to recruit.

It's time the board closed the NRC down.  We work hard for our subscription fee, and the NRC is neither a good nor, in my view, reasonable use of that money.  If anyone conducted an objective cost-benefit analysis of the NRC, I doubt any case other than immediate closure could possibly result.  Staff have been cut at RSGB HQ when the money spent on the NRC could keep at least one of them in gainful employment - such as drumming-up more donations, or going round schools to encourage some interest.

I see very little sign that the society is turning itself around in the way it trumpted it would do a year or so ago.  RadCom is still stubbornly inaccessible to anyone with a nascent interest in the hobby, and I typically find nothing of interest to me in there.  Adverts push for £100 what the magazine should be encouraging members to make for pennies.  The Gigahertz section looked promising when a new author took over, and I was even encouraged to try and take it up.  But it's gone straight back into 'if you don't know how to do GHz work, well we do, so tough' mode.

As far as I can see, the RSGB board is now simply managing the inevitable decline that stems from a long-standing inability to make the hobby attractive to youngsters, and the consequent skew in age profile. Personally, I think the RSGB is beyond repair.  I'd rather read about the exploits of the Real HF Mobile on Yahoo! groups than some dull circuits of interest to no-one in RadCom.

Come on, board members.  Wake up!   The society is dying on its feet, as is the hobby.  And before you have a go at me, yes, I am doing my own bit by setting up a station at a local primary school.  And you know what?  I didn't have to push or glitz it up for them to accept the idea as a good one; they were overjoyed at the prospect, and are keen to get it going as soon as possible. Whilst I've taught university students in the past, I know very little about young kids' education and, naturally, feel a bit nervous about starting off.  But it will be worth it, and I know the kids will benefit from someone pushing science at them for once.

The interest is there, it's just that very few are bothering to develop it.

Contests: Hastening the Death of Amateur Radio

Let me start by declaring a non-interest: I hate ham contests.

Contests are the most banal, pointless, band-destroying activity going.  They take up more weekends than is reasonable,  and ops couldn't give a toss about who might be doing QRP, beacon or weak signal work.

Contests are, in short, simply a direct route to total selfishness. 

And the reward?  Some kudos in some hardly-read DX magazine and a piece of paper on the wall.  What an achievement!

What hope for the poor sod, working all week and wanting to enjoy some DXing on 20m, when all he can hear is shouting, shouting and more shouting.  And some serial numbers.

Mindless.  Pointless.  Selfish.  That's contests.