All I can say this weekend, during what appears to be a CW contest, that amateur radio tests are ludicrous, self-interested pursuits that give not a damn for established protocol, civility or respect for other band users.
WSPR - a sensitive beacon mode with well-established, fixed frequency spots. Wiped out by the CW Test.
JT65 - a sensitive weak signal mode with well-established, narrow frequency spots, regarded as being of scientific value to propagation studies (see rationale for 60m access.) Wiped out by the CW test.
If you think test interference on the bands is OK, it isn't. One can only wonder at the abuse an SSB or wider band OLIVIA operator would suffer if he started transmitting in the established CW portions of the bands. But, somehow, it's fine for CW operators to push aside everyone else.
At least it dismisses the long-held fiction that CW operators are somehow superior and privileged...
Sunday, 30 November 2014
Saturday, 29 November 2014
WSPR Upgrade
Thanks to M1AVV for news of the latest upgrade to the superb WSPR beacon mode software, which can be downloaded from here (15.7Mb.)
Whilst I've only run WSPR 4 for a few minutes thus far, it's immediately clear that it's a big improvement on the WSPR of old.
For starters, received signals are processed and displayed within a couple of seconds, rather than the several tens of seconds it could take the old version if used on older PCs and what now seem like the very anachronistic 'netbook' computers.
The new WSPR also seems to decode pretty much all it hears; sometimes, the old WSPR struggled with signals afflicted by strange propagation effects.
Adjusting the RX noise is cleaner and easier now, and a handy new 'make the next cycle a TX cycle' button avoids having to slide the TX slider to 100% and then back again.
All in all, almost perfect. It even adopts the existing interface settings, though it did take a couple of tries to get the TX to work properly - for some reason, RTS had changed to VOX.
Whilst I've only run WSPR 4 for a few minutes thus far, it's immediately clear that it's a big improvement on the WSPR of old.
For starters, received signals are processed and displayed within a couple of seconds, rather than the several tens of seconds it could take the old version if used on older PCs and what now seem like the very anachronistic 'netbook' computers.
The new WSPR also seems to decode pretty much all it hears; sometimes, the old WSPR struggled with signals afflicted by strange propagation effects.
Adjusting the RX noise is cleaner and easier now, and a handy new 'make the next cycle a TX cycle' button avoids having to slide the TX slider to 100% and then back again.
All in all, almost perfect. It even adopts the existing interface settings, though it did take a couple of tries to get the TX to work properly - for some reason, RTS had changed to VOX.
JT65 - Moving it Along a Bit...
JT65 is a great mode, enabling global DX with very modest, even poor antennas. For many locked-up with moaning neighbours and small properties, it's a real godsend that makes radio possible where otherwise it would be impossible.
But it is slow! Each QSO, if you follow the standard format, takes seven transmissions, meaning each of your CQs, if you are calling, are spaced by no less than nine minutes, including the one minute gap from 73 to CQ if you stick to your chosen even or odd cycle. That's not a lot of QSOs per hour, and the problem becomes acute at grey line time.
I've taken a leaf out of a Russian operator's book, and ditched the RRR to move straight to a <HIS CALL> with RR and 73 all in one. It saves two minutes off each QSO, which is significant when the grey line is marching along apace.
Most are fine with this, but there are compulsive-obsessive perfectionists that will send you a signal report again if you don't fall into his expected, strict pattern. In the rare cases where this happens, I simply move on to another CQ or move to another mode altogether.
So, two minutes saved are two minutes gained, as it were!
But it is slow! Each QSO, if you follow the standard format, takes seven transmissions, meaning each of your CQs, if you are calling, are spaced by no less than nine minutes, including the one minute gap from 73 to CQ if you stick to your chosen even or odd cycle. That's not a lot of QSOs per hour, and the problem becomes acute at grey line time.
I've taken a leaf out of a Russian operator's book, and ditched the RRR to move straight to a <HIS CALL> with RR and 73 all in one. It saves two minutes off each QSO, which is significant when the grey line is marching along apace.
Most are fine with this, but there are compulsive-obsessive perfectionists that will send you a signal report again if you don't fall into his expected, strict pattern. In the rare cases where this happens, I simply move on to another CQ or move to another mode altogether.
So, two minutes saved are two minutes gained, as it were!
Friday, 21 November 2014
TS480 Box for /P
[Standard Health and Safety advice applies - use brain, and wear eye goggles if you feel so dangerous you might damage your eyes!]
My TS480sat became rather redundant after a couple of years of faithful service, largely as a result of frustration with its tendency to drift when used with digital modes.
But the Kenwood is a good rig, and not one to dispose of lightly. It has remarkably good audio both out to the world and from the internal speaker, which in itself makes it a keeper.
The problem with the TS480 is that Kenwood seem to have conceived of it mainly as a car-mobile transceiver, so it's a bit cumbersome, to say the least, to use it as a standalone field-portable unit. If you want to connect digital interfaces, then things become even worse, because the radio body will be so far back that it can't be attached to the carrier.
So, because I operate from windswept beaches where airborne sand is a real problem, I decided to build a box for the darned thing! I used lightweight, exterior grade plywood of 1/4 inch thickness for the sides, with 21mm x 21mm timber to secure the panels and add some stiffness.
The carrier has no base screw holes as standard, so using some standard oil and a sharp metal bit on a slow speed hand drill, I cut four holes. This is perfect, but there is a problem that becomes apparent later - the screws make the side panels bow out slightly when screwed into the wood, so they no longer properly line-up with the 480's screw holes! It would thus be better to make the holes at the base of that 'U' section to the right of the image, and either side of that panel mounting, on the left.
To allow for efficient air throughput to cool the 480, and to permit easy connection of other equipment, I placed the body of the radio lengthwise, with hinged doors to both sides, closed simply by magnetic door fixings, which have an ample 4Kg strength.
Do remember to drill a small pilot hole for all your screws, because if you don't, softwood timber will show a strong tendency to split.
The power cables of the 480 are quite long and stiff, and tangle into a mess. So I just tied them up into a bundle, removed the banana plugs and soldered the wire to panel-mount terminals bolted onto the plywood side. I added a third terminal to permit earthing of the rig. Now the rig is entirely enclosed, with only the need for two shorter, more manageable cables to the battery. Remember to use heavy-duty cable of about 25-30A rating for that.
I reused the 480's carry handle by screwing it into the box, which works well. If I had longer ones, I would have preferred to us bolts, for peace of mind. A lick of exterior varnish is finally applied, to keep it all neat and tidy.
My TS480sat became rather redundant after a couple of years of faithful service, largely as a result of frustration with its tendency to drift when used with digital modes.
But the Kenwood is a good rig, and not one to dispose of lightly. It has remarkably good audio both out to the world and from the internal speaker, which in itself makes it a keeper.
 |
| The basic layout for my box design. The transverse arrangement allows for both good cooling throughput and easy accessory connections. |
The problem with the TS480 is that Kenwood seem to have conceived of it mainly as a car-mobile transceiver, so it's a bit cumbersome, to say the least, to use it as a standalone field-portable unit. If you want to connect digital interfaces, then things become even worse, because the radio body will be so far back that it can't be attached to the carrier.
 |
| There are no base screw holes in the supplied TS480 carrier, so I drilled four on each corner (see text for important comment about this!) |
So, because I operate from windswept beaches where airborne sand is a real problem, I decided to build a box for the darned thing! I used lightweight, exterior grade plywood of 1/4 inch thickness for the sides, with 21mm x 21mm timber to secure the panels and add some stiffness.
The carrier has no base screw holes as standard, so using some standard oil and a sharp metal bit on a slow speed hand drill, I cut four holes. This is perfect, but there is a problem that becomes apparent later - the screws make the side panels bow out slightly when screwed into the wood, so they no longer properly line-up with the 480's screw holes! It would thus be better to make the holes at the base of that 'U' section to the right of the image, and either side of that panel mounting, on the left.
To allow for efficient air throughput to cool the 480, and to permit easy connection of other equipment, I placed the body of the radio lengthwise, with hinged doors to both sides, closed simply by magnetic door fixings, which have an ample 4Kg strength.
Do remember to drill a small pilot hole for all your screws, because if you don't, softwood timber will show a strong tendency to split.
 | ||
| Use flush hinges to make small doors for air circulation and accessory connection. I put the magnetic latch on the top of the box because it's easier to fit and adjust that way; you can put it inside, for a neater finish. |
The power cables of the 480 are quite long and stiff, and tangle into a mess. So I just tied them up into a bundle, removed the banana plugs and soldered the wire to panel-mount terminals bolted onto the plywood side. I added a third terminal to permit earthing of the rig. Now the rig is entirely enclosed, with only the need for two shorter, more manageable cables to the battery. Remember to use heavy-duty cable of about 25-30A rating for that.
 |
| Banana panel terminals attach to the 480's power cable, allowing the cumbersome wires to stay inside the box. |
I reused the 480's carry handle by screwing it into the box, which works well. If I had longer ones, I would have preferred to us bolts, for peace of mind. A lick of exterior varnish is finally applied, to keep it all neat and tidy.
 |
| Nearly finished! The rear, showing the power and earth connection terminals. Rememeber to fit runners to prevent the connectors being damaged! |
 |
| All done! You could also fix an SO239 panel connector for the antennas, for added convenience. |
Thursday, 20 November 2014
RadCom - It's Been a While...
Now, this blog is primarily aimed at encouraging amateur radio on a pocket-money budget.
For example, if you look up the 'I-Am' end-loaded vertical antenna I wrote about here some time ago now, you will save yourself about £200 over the commercial version and have significantly lower losses in the feed system. More importantly, you will learn more about antennas, and even be a little less frightened to experiment with non-established designs; there's little to get wrong, if you follow the basics.
So, it's disappointing, to say the least, to find RadCom, as so many other hobby magazines, reviewing equipment within its pages that doesn't so much save money as encourage you to spend more of it.
Turn to the Christmas 2014 edition, page 32. Here's a review of the 'Whizz Whip' - a simple telescopic whip antenna currently primarily aimed (given its direct male coupling) at the smaller Yaesu mobile transceivers.
Now, there are people who can use most types of equipment, and the 'Whizz Whip' is probably useful in some circumstances.
What I wonder about is whether any situation makes the 'Whizz Whip' a good antenna choice, given that it costs - wait for it - 5p short of £100! As the review diplomatically asserts, a whip like this needs a counterpoise to reduce RF feedback from the I3 current, and help make the situation more stable altogether. It doesn't come with one!
Which kind of brings any sensible operator to ask: why not just use a simple homebrew inverted-L, vertical dipole or something like that? Total cost for one of those can be pennies, maybe a couple of quid if you buy a new SO239 connector (not that you in fact need one of those!)
RadCom repeats the sin, rather, when it moves, at page 61, to review what's ambitiously called a "quarter size" G5RV. At least this only costs £24.99, giving the maker a pretty low margin all in all.
But, come on! Why would you buy an antenna like this? Can't you cut some wire and solder?
Let's imagine you have little space, which is the justification, it seems for the review. You can build your own twin-fed dipole for maybe £15 if you bought all the stuff, a lot less if you have an established junk box. You don't have to give it a name - it's not really a G5RV at all, more a doublet.
What really annoyed me about the '1/4 size G5RV' review was its use with 30m - that's 100 feet - of Mini-8 coax. Whaaaaat? 30 metres? If you mounted the antenna at 10m, and your garden is meant to be small (the justification for the antenna and review), that gives you 20m of coax to eat up somewhere on the ground, remembering that the height is covered by the twin line!!
I think a realistic assessment ought to have been made with no more than 15-20m of coax. Of course, the SWR figures would be somewhat worse under that condition, due to coax losses being reduced. Even then, it's a question as to why you wouldn't simply build a shortish doublet fed only with twin to a 4:1 current balun and a tiny section of coax to make it to the ATU - far lower losses even at very high SWR - and cheaper. At 5m a side (2m longer than the commercial unit), you could work 20m and up efficiently.
Quite why RadCom is reviewing a quadcopter (p68-69) is anyone's guess. But that guess might be related to the advertising income, given that it featured prominently - read expensively - on the back of last month's RadCom.
And then we come to some stuff about propagation beliefs being wrong. I tossed the magazine aside when I read that one-way propagation might be down to higher noise at one station over another. Tsch!..
For example, if you look up the 'I-Am' end-loaded vertical antenna I wrote about here some time ago now, you will save yourself about £200 over the commercial version and have significantly lower losses in the feed system. More importantly, you will learn more about antennas, and even be a little less frightened to experiment with non-established designs; there's little to get wrong, if you follow the basics.
So, it's disappointing, to say the least, to find RadCom, as so many other hobby magazines, reviewing equipment within its pages that doesn't so much save money as encourage you to spend more of it.
Turn to the Christmas 2014 edition, page 32. Here's a review of the 'Whizz Whip' - a simple telescopic whip antenna currently primarily aimed (given its direct male coupling) at the smaller Yaesu mobile transceivers.
Now, there are people who can use most types of equipment, and the 'Whizz Whip' is probably useful in some circumstances.
What I wonder about is whether any situation makes the 'Whizz Whip' a good antenna choice, given that it costs - wait for it - 5p short of £100! As the review diplomatically asserts, a whip like this needs a counterpoise to reduce RF feedback from the I3 current, and help make the situation more stable altogether. It doesn't come with one!
Which kind of brings any sensible operator to ask: why not just use a simple homebrew inverted-L, vertical dipole or something like that? Total cost for one of those can be pennies, maybe a couple of quid if you buy a new SO239 connector (not that you in fact need one of those!)
RadCom repeats the sin, rather, when it moves, at page 61, to review what's ambitiously called a "quarter size" G5RV. At least this only costs £24.99, giving the maker a pretty low margin all in all.
But, come on! Why would you buy an antenna like this? Can't you cut some wire and solder?
Let's imagine you have little space, which is the justification, it seems for the review. You can build your own twin-fed dipole for maybe £15 if you bought all the stuff, a lot less if you have an established junk box. You don't have to give it a name - it's not really a G5RV at all, more a doublet.
What really annoyed me about the '1/4 size G5RV' review was its use with 30m - that's 100 feet - of Mini-8 coax. Whaaaaat? 30 metres? If you mounted the antenna at 10m, and your garden is meant to be small (the justification for the antenna and review), that gives you 20m of coax to eat up somewhere on the ground, remembering that the height is covered by the twin line!!
I think a realistic assessment ought to have been made with no more than 15-20m of coax. Of course, the SWR figures would be somewhat worse under that condition, due to coax losses being reduced. Even then, it's a question as to why you wouldn't simply build a shortish doublet fed only with twin to a 4:1 current balun and a tiny section of coax to make it to the ATU - far lower losses even at very high SWR - and cheaper. At 5m a side (2m longer than the commercial unit), you could work 20m and up efficiently.
Quite why RadCom is reviewing a quadcopter (p68-69) is anyone's guess. But that guess might be related to the advertising income, given that it featured prominently - read expensively - on the back of last month's RadCom.
And then we come to some stuff about propagation beliefs being wrong. I tossed the magazine aside when I read that one-way propagation might be down to higher noise at one station over another. Tsch!..
Monday, 10 November 2014
'Missing Component', Missing Response.
Last month, the RSGB launched an appeal within the pages of its RadCom magazine, urging members to become active participants in various activities for the society.
It's a really good thing, and one you'd imagine wouldn't need doing, being a society of members.
Many old timers out there, familiar with the RSGB of old, will wonder just how willing the society 'bigwigs' are to listening and surrendering any form of responsibility to 'lay' members.
The answer may lie in the silence generated by my very recent offer to help, which continues a series of correspondence during 2014 with Graham Coomber, the General Manager of the society.
First off, Mr. Coomber is always impeccably polite, and no doubt has an awful lot of correspondence both sensible and nutty to wade through daily. It's to his credit he finds time to respond at all.
But beyond that, it's been clear that, within the old man's club, there's a great reluctance to (a) accept views different from those of the society and consequently (b) that no real change is seen as necessary.
My pet issue has been making the UK a friendlier place for hams in terms of what they can and can't put up before planning needs to be a consideration.
The RSGB, via Graham Coomber, has openly and honestly admitted to me that it has failed, in the past, to win support for any changes. To be honest, I'm not sure how hard the society tried. Worse, it seems the society is using the past as a guide to the future, now concluding there's little point in having another go.
Change takes time. It also takes good skills from someone with a track record of campaigning for change. It isn't something the RSGB seems to have any heart whatsoever for doing, and so the status quo remains. With my 25+ years of successful environmental campaigning (the political, and not 'activist' sort), you'd think the RSGB might show some humility and accept offers of help. It needn't be from me, you understand, but certainly someone who has done this kind of thing before, and has an unusual degree of tenacity.
But it doesn't seem at all interested, not even as an informal representative of the society.
Not much of a member society, then!
Also evident from recent responses from the society has been an over-sensitivity to putting one's views forward. When I pointed out certain changes within Wales, the planning committee instantly rushed, like some kid found red-handed nicking sweets, to phone the Welsh Government.
I was then told that my views weren't correct, and that TAN 19, which governs telecommunications, including amateur radio (clearly as a copy-and-paste afterthought), is not generally considered for amateur planning purposes. The society also said the rules in Wales were much the same as those in England. This is true, but doesn't take into account local development plans, SPGs and the like, all of which can and do affect what happens locally, and can be made legally-binding by way of consent clauses, even if those guidances are not legal instruments in and of themselves. Not until I contacted the RSGB did it seem to realise that an entirely new piece of planning legislation was coming into existence in Wales during 2014-15.
As a regular recipient of and contributor to consultations on planning issues within Wales, I could check to see what input the RSGB had made into the new legislation, which is seen as a significant change to the rules here. Go on - hazard a guess at how much input your society had put into arguing for better planning rules for hams during the consultation? Well, I could find none at all, and a challenge to the RSGB, asking them how much input they made over the past two years has gone without reply for two months now. It's safe to assume your society made no input at all.
Now, is the view - that the official Government guidance document, TAN 19, is not of any real significance for hams - correct?
Well, I would agree that sometimes, TAN 19 may not be considered. But it is where the official guidance on amateur radio lies (and for the most part, surprisingly, makes sympathetic noises.)
What the whole episode led to was my contacting OFCOM last week for help in sourcing any document concerning 'safe' levels of RF for amateur radio. Why? Because I've been keeping tabs on a lot of planning and appeal applications, and 'health and safety' features very frequently in the decision-making, typically by councillors and officers who have next-to-no technical awareness, and set-upon by rafts of objectors fearful of any change, whether reasonable or not.
What happened? Well, I was directed by OFCOM to a shedload of documents, one of which was no longer live online, all dealing with RF radiation from - you guessed it - mobile phones.
And that was the point I was trying to make to Graham Coomber and the society all along: that amateur radio applications invariably become conflated with rules, regulations - and more importantly - fears - about mobile phone 'masts'. If my enquiries about amateur radio installations lead to OFCOM and then to rafts of irrelevant documents about mobile phone safety, then that is where enquiries from planning officers and the public will lead.
Obviously, this is not a good place to be. Unlike the ARRL, we can't even rely on any UK advice on any concerns about RF safety planners and neighbours may have - even if they shouldn't normally be considering H&S (because it's covered by existing laws and authorities.)
Mr. Coomber also told me that a member is "more likely" to gain planning permission if he/she uses the RSGB planning service. It sounds reassuring, but I doubt very much the society has the necessary evidence to demonstrate this claim is true. That's because it would need the RSGB to conduct a large-scale assessment across numerous authorities, submitting identical applications for the exact-same properties, with and without RSGB input, to the same case officer. It would be a very tough experiment to run, actually.
So, the question again turns, in my mind, to whether the RSGB is capable of change, when change requires an abandonment of the top-down, 'we know best' attitude that has undeniably and evidently dominated the society for a very long time. I also wonder how much attention the society is paying to the views of its new PR lady.
Time, as always, will tell. For now, so far as campaigning for better planning rules for hams is concerned, there's little doubt the RSGB is little short of useless.
It's a really good thing, and one you'd imagine wouldn't need doing, being a society of members.
Many old timers out there, familiar with the RSGB of old, will wonder just how willing the society 'bigwigs' are to listening and surrendering any form of responsibility to 'lay' members.
The answer may lie in the silence generated by my very recent offer to help, which continues a series of correspondence during 2014 with Graham Coomber, the General Manager of the society.
First off, Mr. Coomber is always impeccably polite, and no doubt has an awful lot of correspondence both sensible and nutty to wade through daily. It's to his credit he finds time to respond at all.
But beyond that, it's been clear that, within the old man's club, there's a great reluctance to (a) accept views different from those of the society and consequently (b) that no real change is seen as necessary.
My pet issue has been making the UK a friendlier place for hams in terms of what they can and can't put up before planning needs to be a consideration.
The RSGB, via Graham Coomber, has openly and honestly admitted to me that it has failed, in the past, to win support for any changes. To be honest, I'm not sure how hard the society tried. Worse, it seems the society is using the past as a guide to the future, now concluding there's little point in having another go.
Change takes time. It also takes good skills from someone with a track record of campaigning for change. It isn't something the RSGB seems to have any heart whatsoever for doing, and so the status quo remains. With my 25+ years of successful environmental campaigning (the political, and not 'activist' sort), you'd think the RSGB might show some humility and accept offers of help. It needn't be from me, you understand, but certainly someone who has done this kind of thing before, and has an unusual degree of tenacity.
But it doesn't seem at all interested, not even as an informal representative of the society.
Not much of a member society, then!
Also evident from recent responses from the society has been an over-sensitivity to putting one's views forward. When I pointed out certain changes within Wales, the planning committee instantly rushed, like some kid found red-handed nicking sweets, to phone the Welsh Government.
I was then told that my views weren't correct, and that TAN 19, which governs telecommunications, including amateur radio (clearly as a copy-and-paste afterthought), is not generally considered for amateur planning purposes. The society also said the rules in Wales were much the same as those in England. This is true, but doesn't take into account local development plans, SPGs and the like, all of which can and do affect what happens locally, and can be made legally-binding by way of consent clauses, even if those guidances are not legal instruments in and of themselves. Not until I contacted the RSGB did it seem to realise that an entirely new piece of planning legislation was coming into existence in Wales during 2014-15.
As a regular recipient of and contributor to consultations on planning issues within Wales, I could check to see what input the RSGB had made into the new legislation, which is seen as a significant change to the rules here. Go on - hazard a guess at how much input your society had put into arguing for better planning rules for hams during the consultation? Well, I could find none at all, and a challenge to the RSGB, asking them how much input they made over the past two years has gone without reply for two months now. It's safe to assume your society made no input at all.
Now, is the view - that the official Government guidance document, TAN 19, is not of any real significance for hams - correct?
Well, I would agree that sometimes, TAN 19 may not be considered. But it is where the official guidance on amateur radio lies (and for the most part, surprisingly, makes sympathetic noises.)
What the whole episode led to was my contacting OFCOM last week for help in sourcing any document concerning 'safe' levels of RF for amateur radio. Why? Because I've been keeping tabs on a lot of planning and appeal applications, and 'health and safety' features very frequently in the decision-making, typically by councillors and officers who have next-to-no technical awareness, and set-upon by rafts of objectors fearful of any change, whether reasonable or not.
What happened? Well, I was directed by OFCOM to a shedload of documents, one of which was no longer live online, all dealing with RF radiation from - you guessed it - mobile phones.
And that was the point I was trying to make to Graham Coomber and the society all along: that amateur radio applications invariably become conflated with rules, regulations - and more importantly - fears - about mobile phone 'masts'. If my enquiries about amateur radio installations lead to OFCOM and then to rafts of irrelevant documents about mobile phone safety, then that is where enquiries from planning officers and the public will lead.
Obviously, this is not a good place to be. Unlike the ARRL, we can't even rely on any UK advice on any concerns about RF safety planners and neighbours may have - even if they shouldn't normally be considering H&S (because it's covered by existing laws and authorities.)
Mr. Coomber also told me that a member is "more likely" to gain planning permission if he/she uses the RSGB planning service. It sounds reassuring, but I doubt very much the society has the necessary evidence to demonstrate this claim is true. That's because it would need the RSGB to conduct a large-scale assessment across numerous authorities, submitting identical applications for the exact-same properties, with and without RSGB input, to the same case officer. It would be a very tough experiment to run, actually.
So, the question again turns, in my mind, to whether the RSGB is capable of change, when change requires an abandonment of the top-down, 'we know best' attitude that has undeniably and evidently dominated the society for a very long time. I also wonder how much attention the society is paying to the views of its new PR lady.
Time, as always, will tell. For now, so far as campaigning for better planning rules for hams is concerned, there's little doubt the RSGB is little short of useless.
Wednesday, 5 November 2014
Ampro Mobile Antenna - 12m Variant
The higher HF bands have been wide open during the past couple of months, and activity is very high there.
As regular readers may recall, I sold my G-Whip Pro Mobile antenna during last spring, as it was just a little too much fuss to change bands with it. Much better, in my view, to have a handful of monoband whips tuned-up and quickly screw in and out as bands dictate.
Mobile whips are much of a muchness, really - there's not an awful lot of latitude for one to be better than the other, being simply helically-wound verticals, the lower HF ones with loading coils, the upper ones without.
I love 12 metres, so opted for an Ampro 12 from Nevada, for £19.95. Nevada charge a very reasonable standard delivery rate, and their service is very good, fair play. The antenna arrived essentially next-day.
The Ampro, a very slimline design, has a standard 3/8" male screw fitting, which will see it attach to the vast majority of magmounts without any fuss. The whip has a stiff lower section, and then a very lively stainless steel top section which is the part you raise up and down to get the right match to the transceiver.
The top whip is held in place very securely by two small set screws. The only problem is that the supplied Allen wrench is made to a very poor quality, such that it is more round in profile than hexagonal! Accordingly, it doesn't work. But Allen keys are so common that this is not a problem worth worrying about.
Matching is very easy, and remains stable with changing environments. Nearby metal sheds and power lines do affect mobile whips quite a lot, so if you do encounter any difficulty, it's best to take the car somewhere clear of development to match the antenna.
Performance-wise, the Ampro is, in essence, just a piece of wire on a stick, so it works as well as any other wire on a stick would! My first QSO was with a 7U station in Algeria, who was hearing me well enough. A TO station (Guadeloupe) was coming in extremely strongly at well over 59, but I didn't get a chance to have a QSO.
So, yes, this Ampro whip works as you would expect, is a really good price, and robust enough to last many years. I was impressed by the way it shirked-off an encounter with a height limiting barrier at my local supermarket. The springy upper section came into its own, merely whipping back into verticality on clearing the barrier!
Just remember that, whilst your car looks a bit silly with a huge antenna on top, it will typically give you 3dB - that's twice the input and output - over one installed on a tow hitch or eye. It's also easier to match, due to the lack of complicating matters such as heating elements in the rear screen.
Blog's rating
on price: 10/10
design: 9.5/10
performance: 10/10
As regular readers may recall, I sold my G-Whip Pro Mobile antenna during last spring, as it was just a little too much fuss to change bands with it. Much better, in my view, to have a handful of monoband whips tuned-up and quickly screw in and out as bands dictate.
Mobile whips are much of a muchness, really - there's not an awful lot of latitude for one to be better than the other, being simply helically-wound verticals, the lower HF ones with loading coils, the upper ones without.
 |
| The Ampro-12 atop the radio car(!) |
I love 12 metres, so opted for an Ampro 12 from Nevada, for £19.95. Nevada charge a very reasonable standard delivery rate, and their service is very good, fair play. The antenna arrived essentially next-day.
The Ampro, a very slimline design, has a standard 3/8" male screw fitting, which will see it attach to the vast majority of magmounts without any fuss. The whip has a stiff lower section, and then a very lively stainless steel top section which is the part you raise up and down to get the right match to the transceiver.
The top whip is held in place very securely by two small set screws. The only problem is that the supplied Allen wrench is made to a very poor quality, such that it is more round in profile than hexagonal! Accordingly, it doesn't work. But Allen keys are so common that this is not a problem worth worrying about.
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| The top whip is kept firmly in place by two set screws. |
Matching is very easy, and remains stable with changing environments. Nearby metal sheds and power lines do affect mobile whips quite a lot, so if you do encounter any difficulty, it's best to take the car somewhere clear of development to match the antenna.
Performance-wise, the Ampro is, in essence, just a piece of wire on a stick, so it works as well as any other wire on a stick would! My first QSO was with a 7U station in Algeria, who was hearing me well enough. A TO station (Guadeloupe) was coming in extremely strongly at well over 59, but I didn't get a chance to have a QSO.
So, yes, this Ampro whip works as you would expect, is a really good price, and robust enough to last many years. I was impressed by the way it shirked-off an encounter with a height limiting barrier at my local supermarket. The springy upper section came into its own, merely whipping back into verticality on clearing the barrier!
Just remember that, whilst your car looks a bit silly with a huge antenna on top, it will typically give you 3dB - that's twice the input and output - over one installed on a tow hitch or eye. It's also easier to match, due to the lack of complicating matters such as heating elements in the rear screen.
Blog's rating
on price: 10/10
design: 9.5/10
performance: 10/10
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