Finally getting my HF stuff together.

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georgel;n93618 said:
The Carolina Windom IS an 80m OCF.

Frank-Underwood-Eye-roll-GIF.gif


I know brother, I know LOL

I mean the HTPOCFD
 
Got an antenna in the air this morning, thanks to some help from AJ4TF. it's an OCF dipole like was described in this post with about 1' that could be trimmed for tuning. The installation isn't ideal but it's not bad. Better then nothing or a wire on the ground. The balun is in a pine tree and the long run goes towards the house tied at the neighbors fence, the short leg has a little bit of a horizontal angle to it instead of making a 180 degree run. The long side ends a little low and the short side is a little high. It it's an inverted V. I would like to put sn analyzer on it. David, AJ4TF says it will likely be fine with a tuner.

i hooked up my HT and caught a lot of Daytona 500 broadcast between 160 and 80 meters. I heard mention of the NC QSO party from Dare county on 40m and a net in KY as well as mention of NJ and AL. Kind of noisy but I heard some call signs. I think it would do better with a radio with a filter. I heard a lot of white noise and often times a carrier tone, I think. I caught A LOT of digital traffic. I think I got a Chinese radio station too, but I'm not sure. Not a bad start I guess.
 
noway2;n99813 said:
I think I got a Chinese radio station too, but I'm not sure.

A lot of foreign broadcast on 40M in the afternoons, including China broadcast radio and radar.
 
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Wow, yeah update is needed.
(snip)
I decided I wanted an Offset Center Fed Dipole antenna. which by design gives a low SWR on 80, 40, 20, 10 and is easily tunable on most other bands with most antenna tuners. .
Resurrecting this older thread. I finally ordered an HF radio and I am anxiously awaiting the email indicating that it has shipped. In the mean time, a guy I talked to regularly during my morning commute is coming over to my house tonight with an antenna analyzer. I am curious to see what the performance of the one I put up is. My installation was less than ideal and I ended up with an inverted V that isn't quite 180 degrees along the axis (though I think I may be able to make it straighter by tying off to a different tree - will have to investigate. It was basically the same antenna design you used, but installed differently so I am curious to compare.
 
In the real world Matt, I doubt that there is any difference. I would try it like it is to see how it does. Congrats on the radio.
 
In the real world Matt, I doubt that there is any difference. I would try it like it is to see how it does. Congrats on the radio.
We shall find out soon enough. David Macchiarolo, AJ4TF - the guy with the analyzer, insists that the distance to ground and the presence of trees will have a significant impact on the SWR to where he suspects that the radio's built in tuner (can go from 16.7 to 150 ohms or 3:1) won't have sufficient capability to bring it in to successfully transmit without the aid of an external tuner.

From what I saw of the design calculators, the SWR in all of the ham bands is typically 2:1 or better, with 1.5 being pretty common. If this holds, the tuner should be able to bring it in just fine.

In any case, I finally got the notification of the radio shipping. I still need to get my ground rod installed and then some cable run along with the polyphaser installed. I am also planning on getting some copper braid to run to the ground rod as the radio has an RF ground lug, which will be the common ground bus for the system. Once again, my set up won't be ideal as I plan to use the bonus room over the garage, but the distance from ground to the radio isn't too bad. The nice thing about it is that I have a now defunct satellite dish mount right there on teh roof that I can use for my 2m/70cm j-pole and can easily ground it (for safety) too and bring it right into the radio which also does 2m/70cm. I also want to get a 2x1 co-ax switch that grounds the inactive connection and a dummy load. This way I can flip the switch, the antenna end gets grounded out and the radio has a 50 Ohm load - so there won't be any issues if I accidentally forget to connect the antenna and what not.

I'll get there, eventually.
 
Man if you guys had an 80' tower with a 3 element Cushcraft beam for 10, 15, and 20 meters...

If only there was a tower guy around here...

Oh, wait...
[emoji12] [emoji12] [emoji12]

I also do serious grounding, guys. Fully equipped to do all kinds of exothermic bonding, trenching, and driving ground rods. Most soil types, I can get your potential to 1 ohm or less if you've got the money for it. Most cases <3 ohms is sufficient. I can also provide commercial grade VHF/UHF antennas, coax, connectors, etc. If your club sponsors a repeater on some remote hilltop tower site somewhere, guess what? We can service or install those remote sites, too.

PM for more info...

Sent from my SM-G920V using Tapatalk
 
We put the analyzer on the antenna last night. It seems to be resonant in several key bands, but on the lower end of them. This isn't surprising as I made the lines long reasoning it is easier to cut them than to extend them. It also seems to have a moderate Q (narrow bandwidth). Overall, I think it will be workable, but may need to be trimmed, which means getting an analyzer and measuring it. I could also use an external tuner which would bring it more in line, but at the price of not putting as much RF into the air. AJ4TF said that he was surprised at how well it did and he really didn't expect it to work this well.

Here is what we found:
80 meter (3.5-4.0): SWR of 2.1 at about 3.5MHz, climbs to 4 at 4Mhz
60 meter (5.3 - 5.4) SWR of 1.2 at 53.1, 2.5 at 52, and 2.5 at 54
40 meter (7 - 7.3) SWR of 1.5 at 7Mhz, 2 at 7.2, and 4 at 7.5
20 meter (14.0 - 14.35) SWR was lowest at 14.140 at 1.3, at 14.0 it was 1.5 and 1.6 at 14.35
17 meter (18.068-18.168) wasn't a winner at about 4:1 across the band
15 meter - it doesn't look like we measured this one.
12 meters (24.89-24.99( was about 1.5:1 across the band
10 meters (28-29.7) wasn't so good at about 4:1 across the band
6 meters (50 - 54) wasn't great at about 3:1 at 50 to 3.5 at the top.
So in short, it looks like five bands, 80, 60, 40, 20, and 12 were pretty good. 17 and 10, and 10 aren't winners but six may be made workable.

As I mentioned, it looks like it is better tuned lower and that makes me wonder that at the higher frequencies which would be a harmonic if it's sweet spot isn't outside of the band. Consequently, if trimming may cause those to come back into alignment better.

In the short run, it looks like there are some HF areas I can work out of the box using the radio tuner, but I will need or want to get an analyzer and trim the antenna down, as well as an external tuner.

Edit to add, I went ahead and ordered an external tuner. While the efficiency may not be as good as a resonant / low SWR antenna, with low loss feedline most of the power should make it out the wire and the radio will be protected against a mismatch. I opted for an LDG AT-ProII and an interface cable which should automatically tune in sand control the radio power level and output a CW tone to enable tuning.

Now, what remains is the grounding situation. I'm looking at some copper strap, which will tie nicely to the polyphaser plate and provide a nice low inductance ground for the RF circuits. Inside I plan to use a small piece of bus bar for the central ground point and strap the radio and tuner grounds to it.
 
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We shall find out soon enough. David Macchiarolo, AJ4TF - the guy with the analyzer, insists that the distance to ground and the presence of trees will have a significant impact on the SWR .


For sure the distance to ground will have an effect, but I would doubt that it's enough of an effect to make the internal tuner unusable. I'm not much of a 80m op but I don't think you'll see anything shifting in the way of SWR on 40 and higher bands if it's at least 20' or so in the air.

The presence of trees (unless an element is actually touching a tree) shouldn't matter much at all. I've had the tip of a 28' driven element of my yagi a foot or so from the end of the element to a tree branch and not noticed anything significant. There's undoubtedly some loss transmitting into a moisture-laden tree but as Paul points out, it's not going to be such that you'd notice.

If you put a piece of wire up in the air and hook it to a 100 w transmitter, you'll make contacts... congrats on getting on hf! Those SWR numbers look pretty reasonable and the bandwidth's you get are typical ... ya dun good.
 
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Thanks. I appreciate the feedback. If all goes according to plan, I'll put the extra ground rod in tomorrow. One thing I was thinking of, and hoping for some suggestions is that at the top of the ground rod, I'll mount the polyphaser (or two if I put up a VHF/UHF antenna since the radio has both ports) . One if the things they mention in the documentation is that they're NOT weatherproof. I was planning on putting some of that self vulcanizing rubber tape on the coax connectors but I'm thinking it would be best to put some sort of little box over the assembly to keep it weather protected. Any suggestions on this?

Monday, I'll order some copper strap and jumpers to bond the RF grounds to a common point and the strap will get sandwiched in the plate that holds the polyphaser. This should be an electrically clean installation ( I'm not an expert but I've had to solve EMI issues before and studied the works of Henry Ott and Howard Johnson). It's just a bit of a pain, but the alternative is like the lady that runs the "Road Kill Cafe" on the SW ARC repeater. She has or at least had severe interference unless she ran on battery due to insufficient grounding.
 
Sounds like you're making good progress I took the Avenue of covering the polyphase with a little metal box . One other feed line is covered by a rain shield and a drip loop in the coax. It is kind of strange that they're not weatherproof isn't it .
 
Sounds like you're making good progress I took the Avenue of covering the polyphase with a little metal box . One other feed line is covered by a rain shield and a drip loop in the coax. It is kind of strange that they're not weatherproof isn't it .
The more I think about it, some coax seal on the connectors and a box over it will be the way to go. The fact that they're not weatherproof seems absurd when you consider that the recommended installation method is clamped to the ground rod, outside, and you don't want the discharge to be inside the house WTF?

I ordered the grounding block that I'll mount to the desk (that I need to get) along with some braided jumpers with lugs to go from the radio and tuner, and the strap that will run from there (bolted with SS hardware) to the plate on the ground rod. I got a bulkhead pass through connector for the coax and my plan to make it look neat and orderly for the wall penetration is to put one of those frame only electrical boxes in and put the connector through the cover and cut a slit in it for the copper strap or just run in underneath the cover.

The ratio and power supply are due in today, the tuner tomorrow and the grounding stuff on Wednesday. With any luck I'll be on the air this coming weekend.

I finally ran into my neighbor yesterday and they have no issue with my 80m dipole being tied off to their fence, but it's not like they see it anyway. They finally noticed it recently when driving home in the dark and spotted the insulator. Their teenage son said, "What the hell? Is that a grenade?" Then they started looking at it and got a bit wigged out noticing that it went up into the trees. Then they figured it was something related to the DirecTV dish.....
 
No, #4 wire is the plan, the 1/8" x 2" flat bar is to mount the Polyphaser in (stud mount) and the ground rod is connected to the flat bar. I found the solid copper flat bar on ebay, no one has it locally except some copper plated stuff. Since I don't have it bonded yet, none of it is assembled, I just disconnect the coax every time I am done using the station.

When I had my first dipole set up, I had a female PL259 connector connected to the station ground. When I wasn't using the antenna, I'd disconnect it from the input to the watt meter, and plug it into the grounded connector. This kept the entire antenna at ground potential. Later, when I put up the tower and the Mosley TA-33, the entire antenna is at DC ground, so the grounded connecter wasn't needed for it.

My low-band equipment hasn't seen the light of day in 25 years... Probably won't even fire up if I ever dig it out of the boxes...:(
 
Got the radio installed. That was a chore. Started Saturday by driving two additional ground rods, one by the corner where I put the radio and one on farther down from where the main electrical one is. Bound the three of them together. The main electrical one had a #6 wire coming out of the utility box to a bonding lug on some cable that looks like it was exothermically welded. Dug down but didn't see the rod. Noticed the other utilities bonded to the #6 so I got some bronze split bolts and clamped to the #6 after sanding it to clear the corrosion, so they're in close contact for a couple inches. Mounted a polyphaser on one rod, wrapped it the self vulcanizing rubber and electrical tape. All the stainless hardware was treated with copper based anti seize lubricant. It's partially buried and I'm going to put s box over it to keep water out. Ran a ground strap (1" flat slid copper) along with the coax and put a box (side frame that doesn't pinch) that can mount a plate with a coax connector. Need to get a metal plate and drill it out.

Upstairs I put together a copper ground bar. Cut a small piece of copper bus bar from another rod and used that to bind the 1" strap, used 12" flex straps to go to the ground on the radio and tuner. Again used anti corrosion stuff on the stainless for the dissimilar metals. Wired up the power supply, and everything, and turned it on.

Seems like the lower bands, 40 and 80 are where most of the traffic is. The upper bands seem dead. Think 6m is on the 2nd antenna input with the 2m and 70cm, so I can't see that right now. I found a few guys using full AM on 80M, one net and one chug calling TEST and then CQ just when I happened to tune in. Talked to him using AM on 80M. He was up n Lughtfoot, VA and the net seemed to be around SC and GA with a lot of 4 call signs. Picked up some CW, some of which was slow enough that I could copy it in my head. I think I caught the end of a QSO. Recognized the CQ easily enough too,

This morning I wanted to see if it was better with the darkness and caught some SSB in English. Yesterday I caught some talk in a language I didn't understand. Lots of digital out there and lots of signals outside the ham bands. It's easy to see with the waterfall display. Tune in and if you hear a voice with a carrier try AM. Lots of Mexican or further south radio on the short wave (160m and below). Caught some US AM radio and some that had a British variant accent.

The antenna seems to work better on the lower frequencies, or else the upper ones are just dead. I also discovered turning on the digital noise reduction, even at the lowest level gets rid of a lot of hiss and makes it easier to hear. The Yaesu FT991 is pretty easy to use, but it will still have a learning curve.

Now, I'll just have to join in next time we try having the local net.
 
I find some traffic on 17M and 20M sometimes but a lot of language that i do not understand. 17 is used by a lot of mobile HF guys out west. You have to really slow down and call or catch a conversation and join in.
 
Congrats. Sounds like you did a good job of grounding. Tying into the main service entrance ground is important.

20m is going to be your "money band" in the mornings and afternoons...say, until about 5-6 pm. from 4-6 PM 20 will produce some surprisingly good DX even at this part of the sunspot cycle. 40-80 is always full in the evenings. Likewise 10-12-15-17....check during sunlight hours. There's always someone on 20 during the day. Make sure you're in USB mode! :)

80M is where I hear a lot of stuff that's in language I (thankfully) don't understand.... :)
 
Congrats. Sounds like you did a good job of grounding. Tying into the main service entrance ground is important.

20m is going to be your "money band" in the mornings and afternoons...say, until about 5-6 pm. from 4-6 PM 20 will produce some surprisingly good DX even at this part of the sunspot cycle. 40-80 is always full in the evenings. Likewise 10-12-15-17....check during sunlight hours. There's always someone on 20 during the day. Make sure you're in USB mode! :)

80M is where I hear a lot of stuff that's in language I (thankfully) don't understand.... :)
I made my first SSB contact last night. There were some guys up towards the NE that talk on 80m routinely at about 8pm. After lurking for a while I joined in. The one guy is located around Penn State Univ and he was clear. There was one in NH that was supposedly having amplifier issues and running low power. His signal didn't even show in the water fall display but I could make out a lot of what he said. I was running 75W (chosen at random) LSB and they repeatedly said my audio signal quality was "beautiful" and wanted to know what I was running.

My only "issue" was a finicky tuner, an LDG AT-100 ProII, which is a generic tuner that connects to the radio though an interface cable. When you do a tuning cycle it's supposed to tell the radio to output a CW tone as it needs RF to tune. For some reason it wasn't wanting to, and I tuned off band of those guys she started transmitting call sign and "test". When I would speak, the tuner would clack and do its thing, but stop if I stopped talking. Obviously it wasn't outputting a CW signal(?).

I did manage to see some noise blips on 6m once I tuned to the middle of the band. I suspect my antenna is far enough out on those freq that I needed to match it better to pick up the signal. @htperry was right (in a PM) that tuning on the band will help you receive better, which I mention as a tip for newbies like myself.
 
I may have figured out the tuner issue. This morning I went to look at the connectors where the interface cable goes in the radio and saw that it was disconnected from the tuner, probably happened when I disconnected the antenna yesterday in anticipation of storms.
 
Don't worry about 6M. One has to be pretty dedicated to hear openings there at this point in the sunspot cycle.
Likewise higher in freq than 14Mhz or so... the Max Usable Freq does peak to 15-25 Mhz most days but it's for a brief time (usually late afternoonish/early evening).

Get out there and call CQ...congrats on the antenna and the new rig. You'll make contacts. Call CQ on 40 m and you'll get answers



John
 
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