Initial low power tests

[VE3GZB]

I'll say that this is the most frustrating part of it...

Initially my antenna was sort of an inverted L where I had the uncut radiating wire strung from TV tower to the clothesline, then the radiating wire bent down 90 degrees to terminate at an insulator just outside my window.

When I coupled my (then) 2W transmitter to it, my friend VE3AWA who lives 150km south of me gave me an S9 signal strength report.

Other hams said to me "No no no, its all wrong, it will never work, change it to a Zepp so I can keep my wife happy and keep the transmission line (450Ohm twinlead) close to the house and not be an eyesore."

I did that. And it became worse.

Then I asked again, and hams told me "No no no, change it to a dipole". So I did that. But then I didn't have enough feedline, so my boss gave me a few hundred feet for free, 14ga insulated wire. I made a twisted pair feedline just like they illustrate in the old ham books and magazines.

Then hams told me "No no no, change it to Coax". So at still MORE expense, I got 500ft of Coax and replaced the feedline.

And still NOTHING WORKS!! SWR is still lousy.

Can you see why I'm so frustrated? I'm getting advice but nothing is working within the physical limits of the lot I live on. And I'm not made of money, I'm doing this all just from out of pocket money, I have no credit cards, I'm the sole breadwinner here...I'm at the point where I'm ready to chuck it all. I can make the receiver and the transmitter from scratch but if I can't get straight experienced advice on the antenna, what's the point? It seems to be only a rich man's game.

73s
geo

[W2ZE]

Not to sound flip or make this sound like a flame, but....
Do you happen to have a handbook from say the 50's? It would describe every antenna you mentioned. Even with the monetary and/or XYL constraints, this isn't rocket science. You sound like a pretty smart guy who has built some excellent HB rigs. I guess I don't understand what the problem is: that random wire you first described with a simple T network tuner would have worked gang busters. My OM and I used one at our old lake residence for years. nothing hard, about 250 ft of wire tossed up in several trees, to a feed thru insulator, to the tuner. fed the tuner with coax, one coax to my OM's op position, and another to my novice station in my room.
if you need a handbook, PM me, i'll send you one.

Mike, W2ZE

[W9GT]

Hi Geo,

Whoa......the advice you have received from many guys here is very good....you just have to choose the best solution for you and your situation.  Dipoles are great if you have room for them.  Balanced line feeding the antenna is great, if you don't have a problem with space or aesthetics or the XYL's disapproval.  Using a tuner and an end-fed wire of some sort is not necessarily the ideal solution, but it will work and might fit your situation and limitations.

Whenever you ask for advice and suggestions from a group like this, you're going to get many different ideas and approaches.  We are just trying to help.  Only you can decide which scheme will work best for you.

73,  Jack, W9GT

[Steve - WB3HUZ]

Wire antennas held up with pre-exisisting structures is not a rich man's game.

[W1GFH]

I guess I don't understand what the problem is: that random wire you first described with a simple T network tuner would have worked gang busters.

After reading through this thread, I got to agree. And the random wire would be fitting for that buzzardly breadboard TX.

[VE3GZB]

"Hamcalc" does not run properly under Linux Windows emulation "Wine". It is completely unresponsive to keyboard input.

I have a 1942 WWII Radio Handbook which has many fine examples of transmitters, receivers, etc....and I've been referring to it frequently as well as other QSTs, other text books and whatnot.....so when I've seen that twisted pair worked then but today Coax is what Hams are supposed to use, you can see the conflict?

So I go ahead taking all advice, spend pocket money which I shouldn't, hope my wife is patient with me and all the while I still can't get a signal out.

I do work in RFID for my dayjob (our transceivers cover 1.5 to 8.7MHz, very low power) so the electronics part is natural to me. But the kind of antennas used in RFID are very different than outdoor Ham use. I have no practical experience in constructing and troubleshooting outdoor HF Amateur antenna systems for transmitting, see?

I'm not flaming anyone, please don't misunderstand my vent....it's just built-up frustration at an ever declining return on the work I'm putting into this (I've also been very stressed about my car and the collision, the insurance company, etc....they're nothing but parasites, it's been since May 27 that I've still been driving my now-written off condemned car and only just yesterday the insurance decided to rent me a car, all the while my hearing rings from an inner ear concussion from the collision).

The transmitter clearly does deliver - I can light a pair of 100W incandescent lamps with it. And my receiver is the finest I've ever had. And I've constructed the dipole as per textbook....yet my SWR remains stubbornly high and nothing I've tried seems to help it.

Who would not feel upset at this? So I'm not upset at anyone, I'm just upset at spinning my wheels for no good reason. I'm sorry if I injured anyone's feelings. It was truly not intended.

73s
geo
VE3GZB

[W2ZE]

so when I've seen that twisted pair worked then but today Coax is what Hams are supposed to use, you can see the conflict?

Yes, I see the conflict; but you went out and bought RG6 without asking anyone if this was OK (correct impedance, power handling, etc...). You spent money on something that isn't going to work. You ask questions about how to read a vswr meter. Tom, K1JJ tells you exactly how to cut a dipole. This is rudimentery stuff. Directly coupling a random wire, as shown in the WW2 book, won't work very well. It was intended to display what to do in an emergency. That random wire, and a T network (which by the way would cost you about a whopping 10 bucks at a hamfest to build), would have worked just fine to put a respectible signal with a 100 watt tx.
Not to sound like I'm blasting off on you, but it sounds like you really need to sit down with a handbook from any era, and read it cover to cover, especially on antenna theory. Once you have a good comprehension of what is in the handbook, then start firing away with questions. There are a lot of talented people on this board, but just because someone tells you something, don't swallow it hook, line and sinker. Ask more questions, do some Google searches.
By the way, just my personal opinion: If you have that much going on in your life, and money is really that tight; now may be a good time to shelf all of this, and focus on family and security. I have been off the air now for about 2 years after taking a new job and uprooting my whole life. Amateur radio isn't a big priority for me right now. I get the urge to start doing new projects, then when I get to doing them, I always seem to ask myself, is it really worth it? 100% of time the answer is no.
Take it for what its worth, sorry you have had this much trouble.

Mike

[VE3GZB]

Judging by what I've seen so far, since jumping into this (and bear in my that I've been studying for a ham license since I was a teenager, I'm in my 40s now and electronics is my profession), today's definition of a Ham seem to operate by the size of one's bank account, the amount of land he/she can afford and how much they can spend on factory built rigs, antennas, etc...

This leaves folks like me, with very small lot, very small money but intense curiousity out in the cold. Can't afford a lot that will support a full size dipole or a fancy rig? Too bad for me then, sucks to be me.

Just telling it like I see it and it's a sad state of affairs. No wonder kids today have no chance to enjoy electronics too.

Maybe a long time ago hams, young boys, could get on the air by raiding the neighbour's trash or the family radio, salvaging parts from broken radios, stringing up lamp cord and making a radio system that way, no SWR measurements, it just worked. Except for harmonics, I see nothing fundamentally wrong with that system and wish to employ it.

I have to use whatever I can get my hands on. And if that just happens to be different, I'm not in a position to afford what "everybody else" can get or use....the Coax I got was what I could afford, period. And I only got it becauase everyone else was saying that twisted lead was not good (forget about the fact that it's used in just about every vintage ham publication).

Advice is nice but when it involved spending gobs of $$, then it's not employable at my budget.

73s
geo

[W2ZE]

Advice is nice but when it involved spending gobs of $$, then it's not employable at my budget.

I never said that, quite the contrary. This hobby can be had at the cheap. My point I'm trying to make is don't take everything said here as gospel.

If 10 bux is gobs of money, ham radio should be the least of your worries.

I'm not going to get into an argument, only trying to help ultimetely; but trying to lay the cards on the table with realistic goals here.

I wish you well.

Mike

[Steve - WB3HUZ]

Mike is right. If money is that tight, you should consider putting amateur radio aside. You seem to be causing yourself much consternation and stress over something as relatively unimportant as amateur radio. I also understand amateur radio can be also be a relaxing and enjoyable activity that is a nice break from the real world.

That said, if you wish to continue, it seems to me that you need to build an antenna tuner. No matter what sort of antenna you install at your location, it will likely be short/small for 80 meters. This indicates a tuner is needed.

[KD6VXI]

How about a loop around the house?  If you have plastic raingutters, all the better.

Seems the first problem you have is the wife, you need STEALTH.  OK, a hidden in the eaves loop is pretty hard to see.  Otherwise, you already have your dipole.

BUT, with all the dollars you've spent now, you have coax that's designed for 75 ohms, and an antenna that should be close to that, and a transmitter that has variable matching in it (pi net or something similiar, not a solid state broadbanded type), and you have an SWR meter that's designed for 50 ohms.

Sounds like your problem is now the SWR meter is incompatible with everything else.

Here's a simple thing you can do, try winding a coaxial balun choke at the feedpoint of the antenna.  It sounds like you have enough coax to do so, and it doesn't have to be large.  http://www.k1ttt.net/technote/airbalun.html is your friend.  That will HELP you, but not eliminate ANY of your problems.

I'd say it's time to learn how to either prune your antenna for resonance, or it's time to sell everything and take up fishing for flys.

Your coaxial cable doesn't like a mismatch, so pruning the antenna for resonance and a 1 to 1 is what you need to do.  This is BEST done at the feedpoint, as the coax will act as a transformer if it is NOT terminated in it's characteristic impedance (in your case, 75 ohms).  Using the SWR meter at the feedpoint means this effect is unable to happen, and when you have it 1:1 at the feedpoint, it BETTER be 1:1 at the transmitter end.

If that isn't possible, it's still possible to get a 1:1 through your coax, but it might take a bit more trial and error, and you MIGHT end up using the coaxial cable as a transformer.  OK at a couple hundred watts, NOT OK at a couple of kilowatts (with the coax I believe you have)...  Keep that in mind, once you get this all working and decide to upgrade your final(s).

Without having a choke balun (or other style balun) at the feedpoint of the antenna, your coax will also have RF on the shield.  This usually pisses the wife off by screwing with her non RF friendly devices (TV's, radios, toasters (extreme case), etc).  HOWEVER, if you don't get any interferience, this can actually ENHANCE your signal.  There are antennas DESIGNED around this phenomenon....  I prefer my ANTENNA to do the radiating, and the transmission line to transmit the signal from connector to connector...  BUT, as Mr.  Varney (G5RV) proved, it does work, and it makes a decent antenna.

You are at the point where you're dangerous.  You know enough to get into trouble spending dollars, which you admit are tight (same here, I'm STILL scrounging my caps and inductors to make my link tuna...  It's been a couple months now.  I took a motorcycle into a wall at 130 mph, and am raising my 2 sons by myself.  100 percent disabled, blah blah blah...  I found CB linears with sweep tubes to be a PLETHORA of parts, if you happen to have old CBers around that can't afford to retube their amps anymore..  A Palomar 350Z netted me 3 caps all the same as well as 2 inductors the same and another slightly larger...  Cost was diesel to go get it, no power supply, no boards, nothing, just a couple output networks in it), but have ALMOST enough knowlege to get it right on your own.  And PLEASE don't think I'm talking down or slamming you, because that is the farthest from the truth.

See if you can find a newer copy of a handbook, or get on google and research.  Your handbook is a bit dated, probably doesn't discuss coax and the inherent problems with it, and that's why you're in trouble now.  Bill Orr also has a great book, The Radio Handbook.  I've a copy of it, and hundreds of copies of books I've downloaded off the internet for free, including some out of print that are FULL of info...  Even on here, I've read about things (Collins Coupler) and someone else chimes in about it (Don) being a Pi, that led me on a half day research about it, a trip to India someone made back in the imperialistic days, etc.  And now I'm rambling.

Anyway, don't give up.  Yes, this IS an appliance operator hobby today, and because of that, it's getting harder to junk box stuff.  You CAN'T go pick up a tubed TV on a street corner anymore, and because of that, you can't get a tubed rig going for nothing.  BUT, guys are using the transistors that have replaced the 6LF6 and other tubes in the horizontal outputs, and using them now in transmitters...  SO YOU CAN JUNKBOX THINGS!! (but, you can't go scrounging at the dump anymore, and people get pissy when you dig through their neighborhood trash, yes, times have CHANGED)

Get your antenna resonant, bud.  Try 468/Freq.  Then half that, and that's the length each side of your dipole should be.  Add a foot, and then cut equal lengths off each side until you get the SWR down.  If you do this at the feedpoint, try to get a 1.3 to 1.5 SWR, and you <<should>> be near 75 ohms at the feedpoint.  Run the choke balun in your coax, down to the transmitter, and load it up, see what you get!

You also might want to try building a field strength meter.  An untuned one can be built REALLY inexpensively, and could REALLY help you with the antennna tuning.  Or a current meter, but I think a FS meter would cost you literally, a couple bucks at most.

Hope this helps.  Don't get too discouraged.  No, this isn't ham radio of the 40s.  This is the ham radio of the new century, where we hear about people making contacts by plugging in a headset to their PC, and no radio is involved.  I don't get it, I'm like you, I want my stuff to glow and reverberate (mod iron) when I talk!!!  (this coming from a guy who runs a Yeasu the size of a CB radio!!!)

--Shane

[WA1GFZ]

Every time someone tells you to spend money a bell should go off.
Any idiot can give you bogus advice. Get a couple inductors and a couple variable caps and I guarantee you it would be easy to match a hunk of wire of any configuration to act as an antenna. AS an RF ID guy you should know this.
This is how many of us started in ham radio as kids with no money.
Coax balun will not eliminate near field radiated emissions from the antenna so don't waste your time with it.
Drive a ground rod in the ground or bury some wire and build a little T or L tuner.
Run coax between the tuner and rig. Put up some antenna wire where ever you can and play with the tuner to get a match. I worked a lot of DX with a random wire antenna using a L network and 100 watts.

[N3DRB The Derb]

I'm sending him some stuff. swr meter, 2 rf ammeters, a UTC S20 mod transformer. I understand what he's going through, I was at that point with the Gonset Amp and just had to do something else to keep my morale up. I'll go back and hit it.

MY biggest problem is I dont have anymore balls. I used to just fire up an if it smoked, it smoked. Now I go through all kind of machinations and excuses about what MIGHT happen. 

Geo, just put it aside for 1 week and then go back to it. You'll feel 10 times better.

personally, I much prefer the pre war handbooks. For one thing, there's little or no crap in the rigs about audio clipping, limiting frequency response, etc. etc.  The handbooks after WW2 are polluted with what the Signal Corp.
taught them makes good communications for the military.

[N3DRB The Derb]

change it to a Zepp so I can keep my wife happy

geo, the one thing I can say is that nobody on this board gives a damn about if your wife is happy.

That's your business.

[The Slab Bacon]

change it to a Zepp so I can keep my wife happy

geo, the one thing I can say is that nobody on this board gives a damn about if your wife is happy.

That's your business.

Sometimes you have to envoke Murphy's golden rule  "He who has the gold makes the rules!!"

[WA1GFZ]

Frank, if I get the deposit slips, do I wear the pants?

[WBear2GCR]

EZ Dipole tuning:

Build your dipole/inverted V so that the ends are held up via ropes.

A pulley is nice if you can manage that, but not necessary.
(Note: if you are going over trees you will need to move that rope at least twice a growing season to prevent it from being grown over...)

Polypropylene (dacron) is best, Nylon second. Avoid all other materials and blends. They will UV rot and die fast. Anything is good if you have it on hand to get it up... always use what is on hand!    Fix it later!

Now build your dipole in length to about 3 feet or so longer on each end than needed according to the formula for the frequency of interest (3885?).

Attach the dipole to the end ropes at a point about 4 feet from the end of the wire by making an appropriate loop in the wire, letting the remaining wire hand down.

Now you pull the ant up, and check ur SWR from one end of the band to the other, noting where it seems to get lower. Probably on one end of the band or another, although sometimes you get a null in band.

If the lower SWR is at the high frequency end (or out of band) then you need to lengthen the wire (add wire to the ends). If it is at the LF end (3500) then you need to shorten the wire. That is what we're hoping for actually... so take the end and bend up a foot or so and tie it around itself! Go check the SWR again. The resonant point ought to have moved up in frequency... continue until you get it at the center freq of interest. This requires a few up/down trips of the ropes.

I've always been able to get my dipoles working in band very quickly by this method. The only thing that may screw it up is if there is other "stuff" interacting with the dipole causing it to resonate somewhere way off the nominal frequency it is cut for.

Sometimes you'll only need to adjust a few inches.

There is likely a way to find out-of-band resonance using a receiver, but I can't think of what that might be at the moment... a grid dip meter might be handy for this... anyone want to comment on how to couple a grid dip meter to the ant??

              _-_-WBear2GCR