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Holy cow! Foof! Those are big. Military grade I'm sure. Those are TV antennas or did I miss it?
They are Ham (amateur radio) antennas. The one in the link is for three of the Ham bands: 20, 15, and 10 meters, which are 14, 21, and 28 MHz.

A more popular, and less expensive ($650), antenna is the Cushcraft A3S.

Cushcraft A3S Antenna2.jpg
 

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Do you think it would be feasible to put some VHF directors on the middle beam of the DAT? Interspersed with the UHF directors?
Yes, but I'm not certain exactly how to do it because I don't have an HD7698P antenna to see how Winegard did it.

There are different ways to make a director function on more than one band. Cushcraft uses traps, but they are complicated and have a bandwidth that is probably too narrow for a TV receiving antenna.

Trap Dipole for 20-15and10_1.jpg


Another method uses elements that are close to each other for active coupling as in the link to the huge antenna by Calaveras.
What to Expect from Multi-Band Yagis
http://on5au.be/content/a10/ant55.html

The Winegard method seems very simple, but the exact measurements are unknown to me:

Winegard HD7698P unfold_directors_1.jpg


The goal of the dual-band directors is to increase the VHF-High gain without reducing the UHF gain of the antenna.
 

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Rabbit, I am willing to experiment here if you can suggest practical guesses...
if you can suggest something like " extend director length 50% on the second to last one"

I have easy access. I am motivated, but totally ignorant of everything ...even which parts are VHF.
 

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Discussion Starter · #25 · (Edited)
Rabbit, I am willing to experiment here if you cannot ⁰0⁰1 assuggest practical guesses...
if you can suggest something like " extend director length 50% on the second to last one"

I have easy access. I am motivated, but totally ignorant of everything ...even which parts are VHF.
I'm not sure where that would go. It sounds like you have the will, but you need the way. Are you modifying the Televes DAT also?
 

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Yes. I am modifying one to get better VHF. Now I am using thick aluminum wire (from twisted cable) to increase size of reflector.

Do you think the directors are more relevant to HI-V Ch. 11? What about lengthening each existing director...say double the width?

OR, I can increase length as you have done.

Thanks
 

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Discussion Starter · #27 ·
Yes. I am modifying one to get better VHF. Now I am using thick aluminum wire (from twisted cable) to increase size of reflector.

Do you think the directors are more relevant to HI-V Ch. 11? What about lengthening each existing director...say double the width?

OR, I can increase length as you have done.

Thanks
I wonder if you couldn't intersperse VHF director elements on the middle boom? Rabbit was talking about the way Winegard does them with the Dual Purpose directors on their antennas...

I was only interested in increasing the UHF capability on my Televes. I've never investigated how to improve the VHF but sounds like a good project.
 

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If you're going to add/change elements to an existing antenna you need to model the changes to see what happens. Otherwise you're just taking stabs in the dark and the changes will likely not work and/or degrade the existing antenna performance.
 

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well, I am totally impressed. I will have to to put things in context ( your rabbit ears ). You must be real far out...

I have what appears to be a smaller (later) version of LR MIX DATBOSS. I need greater VHF from it. Specifically
VHF- 12
I have two L/R Databosses and even there the VHF is not nearly as strong as UHF on these, UHF is 90% of the design and makeup of the antenna. There exist, single station antennas which would work well if you only needed on VHF channel at all.
 

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I wonder if you couldn't intersperse VHF director elements on the middle boom? Rabbit was talking about the way Winegard does them with the Dual Purpose directors on their antennas...

I was only interested in increasing the UHF capability on my Televes. I've never investigated how to improve the VHF but sounds like a good project.
I question whether it would actually be worth the trouble if it even works at all. These antennas are already crowded and the careful way the UHF was designed with three different length booms to reject LTE from above and reflect from below, anything you add would throw it off.

The only way for strong VHF is to go big as the wavelengths are just that long. I am dabbling with the idea of a DIY LPDA which will always be bigger than a Yagi for the same gain but has many advantages. Some of the calculators I have found I have only dabbled in. I would only design an antenna to cover channel 2 to 36 as in the USA there are no more high UHF channels. The trouble is that the part of the antenna that can be skipped is the tiniest part but it would be that much more LTE proof if it cannot receive those frequencies in the first place. There is one low VHF channel in Palm Springs which I debate whether I need it based on content but about the time I designed a high vhf to uhf LPDA there would be more stations that pop up in the future. It was really easier in the 2000s when all digital channels were UHF as the antennas were compact. I am serious about a DIY LPDA as they can be designed to already be 75 ohms and need no balun, at least one person here has built their own I believe. What look like booms are actually plenums and their spacing, side height and everything determine the impedance.

I live in a winter stopover for many species of birds. Will the Televes antennas I will start with handle them? I have heard stories of people just buying a Blonder Tongue LPDA after birds wiped out their consumer antennas with weight on the elements, pretty soon the supply of Blonder Tongue antennas will dry up as they are not really making antennas anymore which leads one to Wade Antennas. The Blonder Tongue antennas have large foam filled elements.

I am waiting for the remainder of my stuff to mount my antennas, the VHF being so much weaker than UHF on these antennas has me waiting in anticipation. I have some VHF channels I would love to have. I was about to use a Gable mount which I will let go of cheap if anyone wants it. With the length of mast I am using there is a tendency for wind to bend the top mount and it's very impractical to try to guy wire a Gable mount so I have a 5' tripod coming. Then I bought three sections of RCA 1.25" mast sections, they are awfully thin to go more than 9', I could bow it by hand in my living room with three lengths together. I just located a place 101 miles from me that sells 20' lengths of 316 stainless tubing that is 16 gauge. I can up that to 1.5" diameter. The 20' length of 1.5 16 gauge is 20 pounds. The 1.25 version of the same thing is 17 pounds. It's not cheap for the tube itself, in the 200 dollar range but the price for delivery is not much more than I can drive and get it myself. I would rather pay 50 for next day delivery than try to rig a 20' length of tubing on my pickup truck and maneuver it for 101 miles and worry the whole way. Has anyone else gone this route for masting? Yes it be guy wired and have two Televes LR Databoss antennas and I am hoping, an FM Omni on top or below the other two. The highest wind speed ever recorded here is 59mph.

By the way, I edited the FCC Off Air table for the Televes meters so it tops out at channel 36 and saved it somewhere as I saw you used one of their meters in your pictures. Did you ever hook a phone via USB to it? You could get better screenshots that way. I had no trouble getting Windows 10 to load a driver for it but the Windows app doesn't like Win 10 for other reasons, the dependencies. An earlier version of Windows 10 would likely work. I would so much rather use my 17" laptop or just get the programmer.
 

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The only way for strong VHF is to go big as the wavelengths are just that long. I am dabbling with the idea of a DIY LPDA which will always be bigger than a Yagi for the same gain but has many advantages.
I've built both. The 22 element high VHF LPDA has 1 dB or so more gain than the 14 element yagi. I don't think the 1 dB additional gain is really worth almost double the size and the LPDA is much heavier due to the double boom. Plans for the yagi are here:


Both the LPDA and the yagi require a balun as the antennas are balanced feeds. Four Fair-Rite VHF beads over the coax seem to work okay for the balun.

3088587



3088588
 

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I've built both. The 22 element high VHF LPDA has 1 dB or so more gain than the 14 element yagi. I don't think the 1 dB additional gain is really worth almost double the size and the LPDA is much heavier due to the double boom. Plans for the yagi are here:


Both the LPDA and the yagi require a balun as the antennas are balanced feeds. Four Fair-Rite VHF beads over the coax seem to work okay for the balun.

View attachment 3088587


View attachment 3088588
Pretty impressive setup in both examples. I'm curious as to how much gain you got from the LPDA as other examples I have seen for a high vhf LPDA are reported to have just over 11db gain with a boom length of 8 feet.
 

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Pretty impressive setup in both examples. I'm curious as to how much gain you got from the LPDA as other examples I have seen for a high vhf LPDA are reported to have just over 11db gain with a boom length of 8 feet.
The modeled gain for the 14 element yagi is shown in the attached graph. I don't have a graph like this for the 22 element LPDA but it was about 1 dB more gain than the yagi in real world tests on channel 9. The LPDA will have a different shaped gain curve. It'll probably start high and slope down as the frequency increases.

I doubt anyone can get 11 dBd gain out of a high VHF LPDA on an 8 foot boom. It's probably 11 dBi or 8.8 dBd. There are a lot of claims for antenna gain running around so I'm skeptical until I see the modeling output.

3089433
 

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Discussion Starter · #34 ·
I question whether it would actually be worth the trouble if it even works at all. These antennas are already crowded and the careful way the UHF was designed with three different length booms to reject LTE from above and reflect from below, anything you add would throw it off.

I live in a winter stopover for many species of birds. Will the Televes antennas I will start with handle them?

I am waiting for the remainder of my stuff to mount my antennas, the VHF being so much weaker than UHF on these antennas has me waiting in anticipation. I have some VHF channels I would love to have. I was about to use a Gable mount which I will let go of cheap if anyone wants it. With the length of mast I am using there is a tendency for wind to bend the top mount and it's very impractical to try to guy wire a Gable mount so I have a 5' tripod coming. Then I bought three sections of RCA 1.25" mast sections, they are awfully thin to go more than 9', I could bow it by hand in my living room with three lengths together. I just located a place 101 miles from me that sells 20' lengths of 316 stainless tubing that is 16 gauge. I can up that to 1.5" diameter. The 20' length of 1.5 16 gauge is 20 pounds. The 1.25 version of the same thing is 17 pounds. It's not cheap for the tube itself, in the 200 dollar range but the price for delivery is not much more than I can drive and get it myself. I would rather pay 50 for next day delivery than try to rig a 20' length of tubing on my pickup truck and maneuver it for 101 miles and worry the whole way. Has anyone else gone this route for masting? Yes it be guy wired and have two Televes LR Databoss antennas and I am hoping, an FM Omni on top or below
I'll let the other guys answer the technical side of the antenna.

If you're asking about the Televes DAT BOSS LR MIX antenna it is fairly Stout. I think the Box tubing is a little thicker and it's more compact than some. UHF wise but that antenna does everything I need it to do. If you have a VHF Hi station that is weak for distant or both you will need a dedicated VHF antenna. They also have one that does VHF low but I haven't had any success with it at all. Chicago has a few VHF low stations but they are out of reach for me.

I wouldn't worry about this whole LTE problem. There are filters that can eliminate any of that and from what I understand are quite successful. Absolutely a 14 through 36 only antenna would be optimal but not many manufacturers are going to redesign their antennas. They're happy with what they have. So for now an LTE filter.

Since I'm also learning I can't really give great antenna advice.

What I will tell you is Antenna masting is is easy. You don't need stainless steel. And the five foot tripod is great. I bought a 5 ft Skywalker and it is very Stout. However if you're going with a 20-foot mast a 10-foot tripod has a better idea.

Lucky for me right next door is a fence company. I have used their galvanized 1 3/8 in chain link fence top rail. Top rail comes in 21 foot sections. It comes in a couple different thicknesses. They told me the SS 20 is their thickest. It's considered pipe. Next down the line is the cheaper stuff that you will find at Home Depot. That is considered tubing.

There's also electrical conduit that is fairly thick and galvanized also. That's pretty stout. For my main mast I used 1 5/8" SS 40. Wind is your enemy.

Guy wires will be needed on a taller mast. The guy wires must be fastened correctly or all of it will be a wasted effort. Ask me how I know 😌 .
 

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I'll let the other guys answer the technical side of the antenna.

If you're asking about the Televes DAT BOSS LR MIX antenna it is fairly Stout. I think the Box tubing is a little thicker and it's more compact than some. UHF wise but that antenna does everything I need it to do. If you have a VHF Hi station that is weak for distant or both you will need a dedicated VHF antenna. They also have one that does VHF low but I haven't had any success with it at all. Chicago has a few VHF low stations but they are out of reach for me.

I wouldn't worry about this whole LTE problem. There are filters that can eliminate any of that and from what I understand are quite successful. Absolutely a 14 through 36 only antenna would be optimal but not many manufacturers are going to redesign their antennas. They're happy with what they have. So for now an LTE filter.

Since I'm also learning I can't really give great antenna advice.

What I will tell you is Antenna masting is is easy. You don't need stainless steel. And the five foot tripod is great. I bought a 5 ft Skywalker and it is very Stout. However if you're going with a 20-foot mast a 10-foot tripod has a better idea.

Lucky for me right next door is a fence company. I have used their galvanized 1 3/8 in chain link fence top rail. Top rail comes in 21 foot sections. It comes in a couple different thicknesses. They told me the SS 20 is their thickest. It's considered pipe. Next down the line is the cheaper stuff that you will find at Home Depot. That is considered tubing.

There's also electrical conduit that is fairly thick and galvanized also. That's pretty stout. For my main mast I used 1 5/8" SS 40. Wind is your enemy.

Guy wires will be needed on a taller mast. The guy wires must be fastened correctly or all of it will be a wasted effort. Ask me how I know 😌 .
I did not know they made 10 foot tripods. It looks like I am not finished shopping.:giggle:
 

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I'll let the other guys answer the technical side of the antenna.

If you're asking about the Televes DAT BOSS LR MIX antenna it is fairly Stout. I think the Box tubing is a little thicker and it's more compact than some. UHF wise but that antenna does everything I need it to do. If you have a VHF Hi station that is weak for distant or both you will need a dedicated VHF antenna. They also have one that does VHF low but I haven't had any success with it at all. Chicago has a few VHF low stations but they are out of reach for me.

I wouldn't worry about this whole LTE problem. There are filters that can eliminate any of that and from what I understand are quite successful. Absolutely a 14 through 36 only antenna would be optimal but not many manufacturers are going to redesign their antennas. They're happy with what they have. So for now an LTE filter.

Since I'm also learning I can't really give great antenna advice.

What I will tell you is Antenna masting is is easy. You don't need stainless steel. And the five foot tripod is great. I bought a 5 ft Skywalker and it is very Stout. However if you're going with a 20-foot mast a 10-foot tripod has a better idea.

Lucky for me right next door is a fence company. I have used their galvanized 1 3/8 in chain link fence top rail. Top rail comes in 21 foot sections. It comes in a couple different thicknesses. They told me the SS 20 is their thickest. It's considered pipe. Next down the line is the cheaper stuff that you will find at Home Depot. That is considered tubing.

There's also electrical conduit that is fairly thick and galvanized also. That's pretty stout. For my main mast I used 1 5/8" SS 40. Wind is your enemy.

Guy wires will be needed on a taller mast. The guy wires must be fastened correctly or all of it will be a wasted effort. Ask me how I know 😌 .
I did end up with a 20 foot section of 16 gauge 1.5" 316 stainless and it was not cheap and had to be delivered. The 10 foot tripods I saw after you told me about them, look like they need a second place to clamp the mast down low inside of it and look even less sturdy than my 5' tripod which has a place very low in the tripod to tighten the bolts which is cupped so no mast sliding through it, the 10' tripods I have seen thus far look like they are designed mostly for height rather than lateral support and assume guy wiring will be used every 10' or so. I am going to use guy wires with large eyelets on the house structure. It has been said that when you pass 10 feet you need them, the 5' tripod will eat at least a few feet of it so it will take some thought while considering that I will have two Televes Dat Boss LR antennas at different heights pointing at two markets in addition to a circular fm antenna. I may or may not need 20 feet of mast but I wanted to be sure. It looks like the tripods are designed so that each leg can be lag bolted after pre-drilling into the studs which I what I want, I really hope.
 

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Discussion Starter · #37 ·
I did end up with a 20 foot section of 16 gauge 1.5" 316 stainless and it was not cheap and had to be delivered. The 10 foot tripods I saw after you told me about them, look like they need a second place to clamp the mast down low inside of it and look even less sturdy than my 5' tripod which has a place very low in the tripod to tighten the bolts which is cupped so no mast sliding through it, the 10' tripods I have seen thus far look like they are designed mostly for height rather than lateral support and assume guy wiring will be used every 10' or so. I am going to use guy wires with large eyelets on the house structure. It has been said that when you pass 10 feet you need them, the 5' tripod will eat at least a few feet of it so it will take some thought while considering that I will have two Televes Dat Boss LR antennas at different heights pointing at two markets in addition to a circular fm antenna. I may or may not need 20 feet of mast but I wanted to be sure. It looks like the tripods are designed so that each leg can be lag bolted after pre-drilling into the studs which I what I want, I really hope.
Damn I just saw this. I don't know why I didn't get the alert before I'm not on this forum everyday simply because there's not a lot of participation anymore at least with the antennas and that's about my only interest. I have the 10 foot E-Z Up tripod and it has 2 mast mounts clamps inside. It is sturdy as can be in fact I had a windstorm that bent my mast.

I'll post that in my own little thread later but some of my good friends here helped me out a lot with that system and they deserve to know what happened.
3115074
 

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Damn I just saw this. I don't know why I didn't get the alert before I'm not on this forum everyday simply because there's not a lot of participation anymore at least with the antennas and that's about my only interest. I have the 10 foot E-Z Up tripod and it has 2 mast mounts clamps inside. It is sturdy as can be in fact I had a windstorm that bent my mast.

I'll post that in my own little thread later but some of my good friends here helped me out a lot with that system and they deserve to know what happened. View attachment 3115074
What kind of reading did you get when they were vertically polarized in that unnatural position or were they pointed at Alpha and Beta Reticuli?
 

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So for now an LTE filter.

Since I'm also learning
Do you mean that you are using an LTE filter plus the televes amp)filter?

I have found that the " datboss mix" is better than "LR datboss mix". I have tried both now. The LR did finally bring in
rf- 12 But, I lost some UHF channels.

Is that because the mast passes through the directors?
 
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