Can I use this antenna?

[wambulance]

Hey folks! First post. I'm so glad to find an active forum because I'm going to get into amateur shortwave listening.

Let me preface my question with the following; I know pretty much nothing about radio technology, pretty much nothing about equipment, and pretty much nothing about shortwave or antennas. As such, I'm an open book with many blank pages ahead that you guys are more than welcome to help me fill in.

For the time being, I have decided upon the Grundig 750 for my radio. I've done some reading in regard to what to look for in a radio, and for the price, options, and the fact that I'm just starting out, I believe I could have made a worse choice.

But anything I've decided to do I like to jump right into, so I know that external antennas are the way to go (remember I know next to nothing, but not nothing). I'm prepared to go the extra mile and install an antenna on the roof and do all of that work. But, for the time being, I want to know if this is a possibility;

The first picture is that of an old (I'm assuming, don't know for sure) TV antenna that was already on the house when I bought it.

This next image is that of the jumble of wires coming down from the roof. All coax stuff on splitters. Mostly Greek to me but I do know that it's connected to that pole antenna.

Just for good measure, I'm throwing in an image of the DirecTV dishes I have on the roof. The one in the foreground is not being used, the one at top is for HD that we upgraded to and is live.

My question is whether or not that pole antenna can be used as an antenna for shortwave. Is that possible? Does it need a mod? Will it work as is if I get it connected properly to the Grundig 750? Or, do I need to forget about all of that garbage and buy some kind of dipole antenna and install it on the roof?

I'm not necessarily looking for the best possible solution right at the moment, just something that will work. The radio will be in a confined area so an external antenna is a must, I'm just wondering if I can possibly use any of the equipment already on the roof until I get around to learning more and installing a proper antenna.

Thanks in advance!

 

[Beetle]

I'd scrap everything except the vertical support for the TV antenna, and then use it as a support for as long a copper wire as you can get. Use convenient nearby trees and other tallish structures (NOT utility poles).

 

[wambulance]

What about just wrapping the copper wire around the whole thing?



The strange thing is that the manual says not to let the wire touch any metal.

I do have a large attic. Perhaps two wooden poles attached to the beams with 100 meters or so of copper wire running around them? How does that sound for starters?

 

[Simon004]

What about just wrapping the copper wire around the whole thing?



The strange thing is that the manual says not to let the wire touch any metal.

Wrapping copper wire around your pole will not work, your manual is correct.

Gotta agree with Beetle, scrap the lot but keep the pole as a support for another antenna. None of the TV antenna you have up will work for shortwave. If you wanted to listen to the VHF/UHF amateur bands then they may be of some use, but they are directional antenna's, meaning you would need to install a rotator to point them in the direction you wanted to listen to. Looking at the pictures they have seen better days aswell, I would keep hold of the larger antenna, the aluminium may come in usefull further down the road if you ever wanted to make your own antenna for VHF use.

For listening to the HF amateur bands you need a big antenna, not really any way around that unfortunately. There are lots of different antenna you could use, but for starters I would probably go for a G5RV, these are very common
and will wok reasonably well for listening, or you could buy a 9:1 unun and just attach the longest piece of wire you can to it, which should also give you pretty good results, although you would need a good ground for best results with the end fed wire.

9:1 unun

If you do have a Hi Z (High impedance) antenna connection on the back of your receiver, then you could just attach a length of wire to it and run it out of the window, then get it as high up as you can. The longer the wire is the better it should work.

 

[W5LZ]

One option you have is to use what you have available now. Won't be the best, but it should pick up more than just the antenna in/on the radio. Figure out which of those cables is going to the old TV antenna. If it's connected to the 'splitter', disconnect it from that and cut off the connector on the end of the cable going to the TV antenna. Short the center conductor and the shield/braided part together. Connect an insulated wire to that point and run it inside to your radio. The trick is to use the right connector to connect that wire to the radio. I have no idea what kind of connector your radio may use, sorry 'bout that. If you can't find one, you can try just wrapping that wire around the radio's existing antenna (alligator clip, or just skin the insulation off of the wire and wrap it that way. What you will end up with is just a wire antenna that's as long as that wire and cable going to the TV antenna. Not the best by any means but certainly better than just the internal antenna of the radio. Since most commercial radio stations use a vertical antenna, and since your 'wire' antenna is basically a vertical antenna, it should do fairly well towards the higher frequencies, sort of.
Antennas get longer as the frequency get's lower. So, the longer the antenna the better to some ridiculous degree (Ridiculous usually means more than about 500 feet. But anything even 20% of that should do fine. Higher is also better.). That wire can be almost anything conductive. Doesn't have to be very large, just strong enough to hold it's self up without breaking. The 'shape' of a listening antenna isn't all that critical at all. Several loops around the eaves of the house does better than you'd think. And at this point, almost anything is going to be better than what comes with the radio, right? Sort of? Running a wire out the nearest window, tying a rock on the end of it and throwing it over the house does well too (watch the windows and that rock throwing).
- 'Doc

If I've guessed right about that user name, I'll bet you may have a pair of forceps that would work instead of that alligator clip. Or maybe an umbilical clamp??
And it doesn't mean anything now, but my Nat.Reg.# was 5 digits and started with a '4'. That sure as hell 'dates' me!

 

[wambulance]

Wow, thanks so much, everyone for the great insight!

Hey, I don't want any of you to think that I'm disregarding any of your pieces of advice. Discussing this with you folks has expanded my knowledge quite a bit and has given me a new idea. I want to take first the advice of Beetle, in regard to the "long copper wire", the advice of Simon004 in regard to the Hi Z (which the radio has!), and W5LZ and put it together for the master plan.

But, I need your approval.

So here's the idea; lots of copper wire. I'll run it up through the ceiling into the attic. Once there... well, I'll just have you guys see for yourselves;

In the attic

See those metal conduits on the ground? That is running live electricity. I'll of course have to ensure that antenna doesn't fall on them. You can touch them, they're not like exposed wires, but still...

Don't fall down! The wire would not come down through this hole, but I will instead drill a tiny hole in the sheetrock ceiling to where it will come down to the radio.

What do you guys think?

So here's my question. If I run this wire through there, lots of wire, let's say 250 feet or so. Can it be run along the boards (suspended of course), then loops back around? In other words, the wire doesn't have to be entirely straight through its whole length, correct?

And grounding. The manual says to put a copper wire in and just let it lay on the ground. That doesn't sound kosher to me.

Greatly anticipating and appreciating all of your advice! Oh and hey, I apologize if my questions seem tedious. I'm brand new to this, but am anxious to get started and learn.

edit; wanted to add, in case I wasn't clear. The primary purpose of this setup will be for listening to SW and occasionally AM.

 

[W5LZ]

From what I can see (not much really) it ought'a work. Now if you could extend that wire out a vent and into the yard, trees, whatever, that'd also work.
Grounding if sort of 'odd' at times. Ideally, you would have as much wire in the ground (radials) as you would in the air. That seldom happens though. Another possibility is to use any water lines (metal ones) as part of that ground too. Works okay with receiving, sometimes causes problems with transmitting because of 'introducing RF into places that water pipe may go. Don't use a gas line though. Two reasons for that. One is that the gas lines have a static charge applied to them by the gas company. The other reason is that any metal gas lines seldom go further than your meter. The connection between the meter and the main gas line is usually a plastic pipe (unless your gas system is quite old). Any/all antennas build up some static charges on them. If it ever get's strong enough, that charge will 'jump' to ground. Not exactly something you would really want around a gas line, is it?
And as a last resort, there's always the third wire ground in the house's electrical lines. Last resort because that 'third' wire also has any 'noise' in the electrical system in your house on it. Another possibility is to run a ground wire to where all those cables meet outside. I'd be willing to bet that there's a ground point there. Lots of possibilities, best for you would be any of them that isn't going to cause noise, and it's fairly easy to determine. Try it. If it's noisy/more noisy, disconnect it. Forget the ground.
- 'Doc

 

[wambulance]

Hey, thanks a lot W5LZ. It is possible for me to run a copper wire to a stake and put it in the ground, with the insulated wire being crunched through a closed window.

In any case, so running the wire in the attic will work, no specific pattern or anything, just length?

I hear ya in regard to getting it outside, but that poses a few problems (I won't bore with the details let's just assume that going from attic to outside isn't on the table). Any design to the wire? Make it criss-crossed? Meshed? A "circle" around beams of wood with a 20 foot radius? Or it doesn't matter, just length and the more the better? 500 feet better than 250? How about a kilometer (joking).

Thanks again!

 

[Simon004]

I really wouldn't be too concerned about an earth at this point, maybe think about that later if you experience high levels of noise.

An antenna outside will always work better, as the signals don't have to pass through your roof to get to the antenna, but you should still get a good enough reception in the attic, especially if your listening to commercial stations as these are usually running quite high power.

Length is important, longer the better, but you would probably get good performance with only 50 feet or so. It really depends of what wire you have lying around that you can use for the antenna. If your going to buy some wire then just go for the cheapest speaker cable you can find, or bell wire, it really doesn't matter what type of wire you use at all. If I was you, I would start close to the bottom of the attic and run the wire around the attic as many times as you can until you run out of wire. I would keep the wire at least a coule of feet away from those power cables, not because of a shock hazard but because going too close could put a humm onto your receiver.

 

[W5LZ]

I really think that 'Simon004' has covered it, mostly. I tend to make antennas longer than really necessary especially for a multi-band antenna only used for listening. If you run that antenna around the perimeter of your attic a time or two, that should 'do' for almost all practical purposes (maybe 4 or 13 times which really is getting sort of ridiculous? ).
The 'shape' of an antenna can get 'tricky' at times. If a simple sort of spiral with some distance between parts of the antenna that are 'close' to each other, is possible, that's what I'd try to do. That 'close' is another one of those variable thingys. As long as they don't sort of touch, it ought'a work okay. Try it one way, and later another way, see if there's any difference and/or which is better. [Antenna length is frequency related, but since this one is for use on a lot of frequencies, I wouldn't worry about the 'right' length too much.]
One simple way of running that antenna wire is to just staple it to those rafters. Dry wood is a pretty fair insulator so that shuoldn't interfere with things at all. Keeping things 'out of the way' is also a nice thing to consider. If you're going to 'clothes line' yourself in the attic, don't fall through that plaster 'floor' (it's embarrassing and a real mess to clean up). Keep things 'practical' as much as possible, if that makes sense.

There's always a "better" way of doing things with antennas! That can get to be a -really- weird goal after one of those 'ridiculous point' thingys. Do what you can, and 'plan' for the next antenna experiment. That's what most people do, no matter what they call it. And the real 'biggy' of the whole thing is to enjoy your self.
- 'Doc

 

[Beetle]

Just about any length of wire will work well for a receiving antenna. Most radio receivers' antenna inputs are voltage driven rather than power or current. Keep the wire as high as you can get it and as long as reasonably possible.

Outdoors is always preferable to indoors/attic. Your attic looks to be a possible source for electrical noise which, of course, you want to minimize.

Do a little experimenting. Running a wire in underneath a window isn't going to hurt anything, although you'll want to make sure the window doesn't scrape the insulation off and make it bare metal to metal. Even on a receive-only antenna, that can cause problems or at least make you thing the antenna system (now including the metal window frame) is performing somehow differently than before... .

But the main thing is, experiment.

 

[wambulance]

Wow, thanks so much guys!

I suppose I'll start with the radio's built in antenna for a control to see how that works. Then I'll add 100 ft of 18 gauge copper wire in the attic and try that. Then another 100 ft and so forth. The issue of electrical noise in the attic that was brought up is a good point to consider, so I want to go 100ft at a time so if I find that it's not working out, I don't have to take down 500ft of wire all at once

W5LZ you crack me up with the bits of humor in with the solid advice. Yep, I'm having fun with it for sure, already having fun getting good ideas from you folks.

But my wife thinks I'm crazy as hell.

 

[wambulance]

OK! Radio and wire arrived on same day. I have to say, I like the Grundig 750. It picks up everything extremely well... except shortwave of course.

I've not attached any external antenna yet, just wanted to play with the radio first and get a feel for how the built in compares for when I install the longwire in the attic.

The FM, AM, longwave, mediumwave (I know some of those are in the same band, just different settings), and airband pick up remarkably well. I even tuned it to 27.185mhz (channel 19 for CB) and had my wife go outside and key up our archaic hand held CB radio and she came in very loud and very clear (as expected, but hey I'm testing it out).

So, it appears I will need the longwire for any chance at ANY shortwave. I mean, the only thing I could get was the WWV in Fort Collins about 60 miles away on 5000khz, and only because I knew it was there, otherwise I wouldn't have known. In any case, I'll report back when I get 100ft of wire to start, then will add sections 100ft at a time.

 

[Beetle]

I even tuned it to 27.185mhz (channel 19 for CB) and had my wife go outside and key up our archaic hand held CB radio

Well, we can't have archaic and eat it too.

(Sorry. I don't get straight lines like that every day... )

 

[wambulance]

LOL!

Hey, now that the sun is set I'm picking up all kinds of stuff on HF. I'm very excited and will begin on the antenna tomorrow. Stay tuned!

Edit; started a new thread on this here.