It could be more than the antenna

This was first published at V44KF.spaces.live.com on 25th November 2007.

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16 months later, and yet there is no sign on the horizon of a simple antenna than can out perform the 20 bucks home brew double tee, top and bottom loaded, vertical dipole antenna.

Some of my ham radio buddies are running from building this antenna just because I am pushing it, but whatever they construct and tryout fall far short and will continue to fall short. Eventually they will accept the fact that a 'vertical antenna' is a 'vertical antenna' and it will always perform the same way every time no matter where or how. And if they really want to work DX on the other side of the world for pennies, without a tower and a beam on the low bands, this is the only way to go. Just like the sun rises in the East and sets in the West, no matter where you go on the planet, this short top and bottom loaded vertical dipole antenna will work superbly. Because that is its nature, and nothing we can do about that.

The antenna is one of the single most important components of a ham radio station. Some hams may argue that the rig is the key. I am not going to argue that, because over the last 40 years of my ham radio hobby I have been close to the receivers in various rigs, from the Eico 753, Heathkit SB100 and SB101, Collins KWM-1, Drake TR-3, TR-4, TR-4C, TR-4CW, R4-C, National NCX-3, NCX-5, Icom 745, Kenwood TS-520S to the Kenwood TS-940SAT. Not a whole lot of receivers, but enough for me to see what goes into them and why they tick the way they do, and also even why they did not tick.

All ham radio receivers can get down to the noise floor. That is, when you connect the 40 meter antenna you can hear atmospheric noise in the speaker. If you don't hear any additional noise over the background hissing noise of the receiver, that rig needs to visit 'emergency' or 'out patients' asap. Every rig, modern and not so modern, should pass that sensitivity test. If the radio doctor gives it a clean bill of health and you still can't get the atmospheric noise in the speaker, that rig need to visit the tune up specialists, to tweak resistors and capacitors, and optimize the receiver circuitry.

I do not understand why a receiver manufacturer would place a 5 watt audio amplifier in a receiver and then fine tune the circuit parameters to only deliver 1/4 watt to the speaker. Maybe it has to do with the price tag. So with a little tweaking you can get up to 2.5 watts of audio output like the bigger brother rig, but without the additional 500 bucks. Maybe it has something to do with the marketing strategy of those days. But these same rig manufacturers also produced a top of the line rig with all the bells and whistles, and technology of the day with a 4 figure price tag. After 20 years some of these rigs are found on eBay at just under half the price of when they were new. So hams waiting for prices on these rigs to drop still further may never get a rig.

The new rigs of the last 5 years do not readily support circuit tweaking by the average ham operator without electronic servicing and maintenance training. That include hams like me. But then if I get the latest 5 figured uncle Sam Icom or Yaesu rig I should never need to do a modification on it. Unfortunately, if you think so you may be quite wrong. No matter how expensive and sophisticated the rigs are they all come off the assembly line with a bug, two, three or four, which hams will discover and write and publish a mod for. I was getting ready to pick up a Yaesu FT-1000 Mark 5 as that followed the TS-940SAT as the top contest rig a few years back, but according to the mods.dk listing Yaesu has propagated the same noisy diode problem over all the models and versons of the FT 1000. That itself is bad, but the procedure to replace that diode is not as simple and easy as it is written. For a pro service tech that may be a walk in the park. But not for me.

So where does that leave us older hams with 10x magnifiers, arthritis, a weller solder gun or 60 watt pencil iron? Maybe looking on eBay for the top equipment of yesteryear. And there are lots of them on eBay these day. Recently I saw a user group where some old timers are not only rebuilding these 20 year old rigs but also offer parts kits for other rig owners to restore these fine rigs. After restoration the only thing old about the rig is the original manufactured date. But the rigs are now working to the original specs or even better, and it did not cost you the arm and leg of a current model rig.

So what are some of the rigs that we can find? Check the Sherwood Engineering receiver data at www.sherweng.com and take your pick. My favorite rigs are made by Ten-Tec, and of course I have a bias. I can always get parts when required, even outside the 7 year availability time frame stipulated by law. It is unfortunate that hams in the USA are not buying more local rigs, made in USA, but are still taken in by the fancy rigs made in Japan, but that's the way the cookie crumbles. Of course the Ten-Tec could also look like a product from JA, if they wanted it to, but maybe the price tag would also be different. You can't have your cake and eat it. DX hams want performance not bells, whistles and styles. IMD is a real big thing for Dxers. The spec is not hard to achieve with the 20 year old rigs, Inrad filters and a mod or two. Not bad for a couple bucks.

But when all is said and done it comes back to the antenna. If you do not place your signal at the right take off angle over the horizon, you can't work the DX no matter how sensitive and selective your receiver. Take off angle and propagation go hand in hand. There is propagation software to help us maximize our operating but I don't get caught up with that unduly, but just stick with the sunrise and sunset tables from On4UN. That is all I really need, but you may prefer more. Vertical dipoles give the low angle that is required for DX, and like I said, it is their nature

This spaces.live concept is rather interesting and I will have more to say on ham radio, but I feel the need to digress on to other topics, including, but not limited to Carnival without the politics, Photography without Art and Artists, the Youths and the dress code in Public schools. I will also add some photographs to spice things up and see where this can go.

Have a great day, enjoy your ham radio hobby, and if you find the time to comment on anything I have said, constructively or otherwise, Thank You.

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