Metal flag pole

[turkee56]

Hello
Need some help on this.
I have OCF antenna and mounted to a flag mast and just bought a new Yaesu ft 991a . It's receiving well but not getting out . Running Rg8x coax about 70 ft and didn't want to cut it so I coiled the rest 30ft up and hung it up outside my window. I know the balun is to close to flag pole. So I made a plastic PVC pipe as a stand off. How far away shud the antenna and balun be from the flag pole I made it 3 1/2 ft .one leg of antenna is going thru some tree branches. Will that affect antenna performance. The antenna is in a inverted vee.i had inverted vee before and only up 17 ft and legs off the ground 3 ft and worked wonderful also between 2 houses. So what else can i do to get this OCF to work .it's a radio waves OCF.

 

[K6GBW]

The balun only need to be a few inches away from the metal mast for it to work. The wire leg touching the tree branches "might" be causing an issue. The 70 feet of coax when you only need 40 is a loss. If you are able to shorten it that would be more power to the antenna. You never said how well it's tuning up or how high it is. OCF dipoles are effected a lot by their height. Raising or lowering the center or the legs can change things dramatically. If the antenna is very low then your signal is likely going straight up and you are effectively an NVIS station, meaning you are only being heard relatively close in about a 300 to 400 mile circle.

Also, at 100 watts you may be getting out, but you aren't being heard simply because band conditions have been weird lately. Even though we've had a lot of sunspots and the SFI has been high, we've had a lot of geomagnetic interference over the last few months. Try using your computer and find an SDR near you. Tune to an unused frequency and transmit on your radio to see if you can hear yourself. If you can then you know you're getting out. If not you may need to make some changes.

 

[dimab]

+1 for SDR test, I've used this site - websdr.org

 

[turkee56]

The balun only need to be a few inches away from the metal mast for it to work. The wire leg touching the tree branches "might" be causing an issue. The 70 feet of coax when you only need 40 is a loss. If you are able to shorten it that would be more power to the antenna. You never said how well it's tuning up or how high it is. OCF dipoles are effected a lot by their height. Raising or lowering the center or the legs can change things dramatically. If the antenna is very low then your signal is likely going straight up and you are effectively an NVIS station, meaning you are only being heard relatively close in about a 300 to 400 mile circle.

Also, at 100 watts you may be getting out, but you aren't being heard simply because band conditions have been weird lately. Even though we've had a lot of sunspots and the SFI has been high, we've had a lot of geomagnetic interference over the last few months. Try using your computer and find an SDR near you. Tune to an unused frequency and transmit on your radio to see if you can hear yourself. If you can then you know you're getting out. If not you may need to make some changes.

I heard stations out west and close seems to receive well. But tx is the problem. Read pamphlet from radio wavz who makes this antenna
Say keep away from structures , trees etc .
I had inverted vee but not ocfd between two houses and apex 15 ft and house had aluminum siding and worked very well. Probably have to me antenna in lower lot but that's 130 or feet away. Lot of loss

 

[turkee56]

I heard stations out west and close seems to receive well. But tx is the problem. Read pamphlet from radio wavz who makes this antenna
Say keep away from structures , trees etc .
I had inverted vee but not ocfd between two houses and apex 15 ft and house had aluminum siding and worked very well. Probably have to me antenna in lower lot but that's 130 or feet away. Lot of loss

The Ocfd is up 23 in the air at apex. Wish I got the 30 fter pole. So much obstacles near Antenna . Wooden shed, trees, and power line about 40 ft away. . Probably all factors in the setup of my antenna.
But like I said between 2 houses and power lines near etc. My inverted vee worked great

 

[K6GBW]

An inverted V dipole is a balanced antenna so they are easy to make work great. An OCFD is, by design, unbalanced, and this causes some issues including common mode on the coax and being more sensitive to height above ground and to surrounding objects. At 23 feet it's pretty low, so any sensitivities are exacerbated. Frankly, the only reason to use an OCFD is to get a multiband antenna, but they are a compromise in performance. Plus, at 23 feet it is definitely an NVIS antenna on all but the upper bands so on 40 meters you are likely sending most of your signal straight up. This isn't necessarily a bad thing. I do mostly rag chews with "Local" stations that are within about 400 miles, so my antenna is rather low intentionally and it works fine.

You can still make OCFD's work, but they are finicky beasts for sure. Another alternative that you might try is using an End Fed Half Wave, but deploying it as an inverted V. I've done this several times by using wood screws to place the transformer (unun) underneath the eave of a house, then looping the wire from underneath the eave to an eyelet and then running the wire up to the top of the mast where I placed a short, one foot, nylon cord with an insulator, and then run the wire back down to a convenient location to tie it off. All I do is pull the far end of the wire slightly away from the mast to hold it away from the metal pole and it works just fine. The EFHW is a pretty tolerate antenna of things surrounding it.

All that said, if you are able to tune your antenna with an antenna tuner then it is probably working fine. The band conditions have been unpredictable at best and even good antennas don't work well when the bands are hashy and trashy. HF band conditions are kind of like surf conditions, some days the waves are breaking great and some days its flat. Don't make decisions about HF antennas based on only a day to two of listening. I always run a new antenna about a month or more before I make any decisions.

Also, if you don't have a common mode choke on the coax near the station you should definitely put one on it. Make sure its outside the house not inside. Common mode riding on the coax that makes it past the chicken wire behind stucco can make a ton of noise, so cut it off with a good choke before it gets in the house. Snap on ferrites on the coax inside the house are good too. Basically choke the crap out of it!

Good luck and let us know what happens.

 

[turkee56]

An inverted V dipole is a balanced antenna so they are easy to make work great. An OCFD is, by design, unbalanced, and this causes some issues including common mode on the coax and being more sensitive to height above ground and to surrounding objects. At 23 feet it's pretty low, so any sensitivities are exacerbated. Frankly, the only reason to use an OCFD is to get a multiband antenna, but they are a compromise in performance. Plus, at 23 feet it is definitely an NVIS antenna on all but the upper bands so on 40 meters you are likely sending most of your signal straight up. This isn't necessarily a bad thing. I do mostly rag chews with "Local" stations that are within about 400 miles, so my antenna is rather low intentionally and it works fine.

You can still make OCFD's work, but they are finicky beasts for sure. Another alternative that you might try is using an End Fed Half Wave, but deploying it as an inverted V. I've done this several times by using wood screws to place the transformer (unun) underneath the eave of a house, then looping the wire from underneath the eave to an eyelet and then running the wire up to the top of the mast where I placed a short, one foot, nylon cord with an insulator, and then run the wire back down to a convenient location to tie it off. All I do is pull the far end of the wire slightly away from the mast to hold it away from the metal pole and it works just fine. The EFHW is a pretty tolerate antenna of things surrounding it.

All that said, if you are able to tune your antenna with an antenna tuner then it is probably working fine. The band conditions have been unpredictable at best and even good antennas don't work well when the bands are hashy and trashy. HF band conditions are kind of like surf conditions, some days the waves are breaking great and some days its flat. Don't make decisions about HF antennas based on only a day to two of listening. I always run a new antenna about a month or more before I make any decisions.

Also, if you don't have a common mode choke on the coax near the station you should definitely put one on it. Make sure its outside the house not inside. Common mode riding on the coax that makes it past the chicken wire behind stucco can make a ton of noise, so cut it off with a good choke before it gets in the house. Snap on ferrites on the coax inside the house are good too. Basically choke the crap out of it!

Good luck and let us know what happens.

Wow can't galvanized pipe anyway. Lowe's was out and not paying for a 10 fter. Even black pipe. I have one hardware store to go and see wow pipe is out rageous

 

[K6GBW]

Yeah, the price of just about everything has gone up this year. Try 1.25" Electric Metal Conduit (EMT). It's cheap, light and totally fine for light weight antennas. Aluminum tubing also works as long as it's for something light weight.

 

[turkee56]

Yea will try conduit . Talked to wireman and says ur best bet if run over 100 ft of coax use RG8U low loss I think 0.8 db at 100. My lower lot is ideal for antennas .But coax runs be over 130 ft ..