Close channel Reception problem

[rabbit73]

Originally Posted by kb4

.....an un related question. I received the xg91 today that I was going to try this weekend and when assembling it I noticed that one boom joint comes together touching each other the one closest to the reflectors and the other two sections have about a 16 th of an inch gap between the booms and though the braces are same length it looks like space to the hole not the slot is a little less on one of the brackets . I could easily modify the hole or the slot to make the boom sections touch each other like I would think they should. I am unclear as to whether this is intended or not. I can call antennas direct tomorrow and see what they say if no one knows. I will try to post pics
https://imgur.com/dSDnzV6
https://imgur.com/eDEBg1N
https://imgur.com/X9n4GxU

Again any help would be appreciated

I don't have a 91XG and have never assembled one. I suggest you wait for ADTech to come by to this forum as he often does. He would be your best source of advice on the Antennas Direct 91XG.

Where did you buy your 91XG?

Also there is an element just in front of the dipole that is permanently mounted to the boom that I have not seen in any pics of the antenna. Just wondering if this is supposed to be there or maybe it was a return and not correct parts.

It is a director that is supposed to be there.



There is also a director that is very close to the dipole driven element on the Solid Signal clone of the 91XG, but it is mounted on the front of the balun enclosure:

[rabbit73]

Here is the WYJJ terrain profile with your antenna at ground level. The signal doesn't clear the hill.



Here is the terrain profile with your antenna at 35 feet above ground level. The signal clears the hill, but it doesn't clear the trees. The software uses the ground elevations but doesn't add the trees.

[kb4]

Thank you for that extra work. I finally found a pic today that I could barely make out the one permanently mounted director . Then for the gap I decided to measure the distance between nearby director elements and even though the spacing generally gets closer toward dipole in the area in question there were one or two before and after that gap that were 5 1/2 inches apart as the spacing was with the gap, so I put it up below the 9032 and swapped coax to it and it works better than the 9032 . Of course it could just be the particular spot its in but I believe there is a significant difference. I now get a few dropouts but watchable and after dark essentially no dropouts. Plus right now its only at about 25 feet so I think it will improve some more if I get it up another 10 feet or so with permanent mount since trees will be about the same. It is probably just at line to barely clear crest of the hill if it even does. Then just hope that when leaves finish developing the signal will hold up enough. The leaves have really developed in the last couple of days even since the pic showing them but most of the close trees leaves are higher than the antenna so we shall see.

I did conclude the antenna was put together correctly because there are 22 of the directors with the the kinda v shaped sets on each side an I assume they are counting these as 4 directors for each peace equaling 88 directors then the permanent mounted piece is counted as 2 directors for 90 then 1 for dipole making a total of 91 elements thus the name xg 91 probably standing for Extreme Gain 91.

It was very windy this afternoon about 25 mph so it was good test for multi path etc which I am sure there will be some of but didn't affect reception much.

It may be a while before I get around to the permanent mount but will let you know what the final results are.

Thanks again

[bobsgarage]

Originally Posted by kb4

I did conclude the antenna was put together correctly because there are 22 of the directors with the the kinda v shaped sets on each side an I assume they are counting these as 4 directors for each peace equaling 88 directors then the permanent mounted piece is counted as 2 directors for 90 then 1 for dipole making a total of 91 elements thus the name xg 91 probably standing for Extreme Gain.

It may be a while before I get around to the permanent mount but will let you know what the final results are.

Thanks again

Hi kb4.
I've been reading through your thread. I think it's great that these others have come to help you. I have just been lurking reading and I'm amazed at what Rabbit has done for you. All the charts, Maps, calculations. And the other advice is been great too. He did the same for me too!

Do make sure when you get set up to give us your results. The 91xg is an excellent antenna.

So, I was reading about your amp choice. There's been a lot made of that LNA-200, you can just search it here and on some of the other forums.
TV Fool felt it was important enough to make this a "sticky" thread":

http://forum.tvfool.com/showthread.php?t=13583

I also have an LN200, and wondering if I can get a little more gain by putting something higher-quality in place of it. I admit I only spent $30 on it and a very good amp is going to cost twice that much maybe you could look into this Kitz Tech:

http://www.kitztech.com/KT200.html

For me I'm just a hobbyist. I do a lot of lurking here oh, and I try not to add things that won't help. But the theory is if an amp is noisy, just replacing it with a quiet amp can give you some help. Cutting the cable length to only what you need is sure to help if you are losing 5-6 DB on a hundred foot run.

And also for what it's worth, I see a lot of recommendations 8 Bay ( like the CM-4228hd) antennas where trees / leaves are a problem. I do not own an 8 bay so I cannot confirm that. I fear that when your trees leaf out, the challenge will be greater.

Good luck my friend, I will be watching.

[rabbit73]

Originally Posted by kb4

.....I put it up below the 9032 and swapped coax to it and it works better than the 9032 . Of course it could just be the particular spot its in but I believe there is a significant difference. I now get a few dropouts but watchable and after dark essentially no dropouts.

Thank you for making the interesting test.

Plus right now its only at about 25 feet so I think it will improve some more if I get it up another 10 feet or so with permanent mount since trees will be about the same.

The general rule is the higher, the better, but when the signals are scattered by an obstruction, the wavefront is not uniform and there will be hot spots and cold spots for the signal. As you move the antenna up and down, even as little as 6", you will find layers where the signal is stronger.

I did conclude the antenna was put together correctly because there are 22 of the directors with the the kinda v shaped sets on each side an I assume they are counting these as 4 directors for each peace equaling 88 directors then the permanent mounted piece is counted as 2 directors for 90 then 1 for dipole making a total of 91 elements

88 for the directors + 1 extra mounted director + dipole driven element
+ reflector = 91

thus the name xg 91 probably standing for Extreme Gain 91.

Don't confuse the Antennas Direct antenna with the Solid Signal antenna. The Antennas Direct antenna is the 91XG, not the xg91. The Solid Signal antenna is the Xtreme Signal HDB91X.

[kb4]

To clear up I have the antennas direct 91XG.
The reason I used the LNA 200 was I bought two of them about 5 years ago and wasn't using the antennacraft 7-13 VHF antenna I did have it on which actually works well without it. Back when I bought it the low noise figure was all the rage. I have looked at other amps such as the Kitztech and johansson I may be trying to combine the 7-13 antenna with UHF and the TVPRAMP RCA I have no longer works at all so was looking for another choice that might be better or more reliable .

Yes I thought of the DB8E but I plan to use the 91XG for another location anyway so if it didn't work I had nothing to loose since it would be used anyway. I also thought if too much problem with multi path that it would be easier to stack the 91XG s.

Thanks to Rabbitt73 in another thread I found out that for the channels I want to receive highest being real channel 34 the DB8E has more gain.


Today there has been very little wind and the reception has been flawless on WYJJ with signal level around 75 to 80 .

Next I will take the 9032 down and put 91xg where it was just to see if much if any difference soon . Then I will wait on full leaves before changing anything else.

I bought the 91XG from amazon to make sure I got it in two days and free shipping on prime but the seller was antennas direct.

I also may play with tilting it up to varying degrees which I think would be easier with the 91xg than the DB8E but not sure since I haven't seen the DB8E.

[rabbit73]

Originally Posted by kb4

.....the TVPRAMP RCA I have no longer works at all so was looking for another choice that might be better or more reliable.

I bought two RCA TVPRAMP1R preamps in sealed boxes; both failed. I can't recommend a preamp with such poor quality control. The Antennas Direct Juice is more reliable and you can add a UVSJ if you want separate UHF and VHF antennas.

Today there has been very little wind and the reception has been flawless on WYJJ with signal level around 75 to 80.

Excellent! OTA signals will vary in strength even without trees.

I also may play with tilting it up to varying degrees which I think would be easier with the 91xg than the DB8E but not sure since I haven't seen the DB8E.

The 91XG has a tilt bracket; a tilt bracket for the DB8E would be a custom job.

[kb4]

Here is a pic of the 91XG mounted below the 9032 temporarily . Yes , I know they are not pointed in same direction only using one at a time.
https://imgur.com/0cpGNL6

[rabbit73]

Originally Posted by kb4

Here is a pic of the 91XG mounted below the 9032 temporarily . Yes , I know they are not pointed in same direction only using one at a time.
https://imgur.com/0cpGNL6

To me, all antennas are beautiful; they are magic.

[kb4]

I know this is more complicated and costly than it needs to be but would a setup something like this have a chance of working ?

https://imgur.com/tpRBcPm

If I did set up a repeater similar to this would both of the antennas have to be identical ?

Is there a certain length of connecting coax to use? and if amp needed would length of coax from receiving repeater need to be same as transmitting repeater?

Would the signal from the other stations closer to that direction cause a ghosting effect and interfere with reception on this channels or just the strongest signal win out so to speak or would I have to filter out those channels?

I saw something similar in another thread where reception was provided to a motel for a signal blocked by ridge I believe.

Mostly theoretical but interesting.

On somewhat unrelated topic for different location at hunting cabin I have a winnegard 8200 for real channel 5 and 13 VHF low and high band and a different antenna for UHF with amp for another market direction that requires an amp utilizing a/b switch. I was considering the channel master CM778HD amplifier to both amplify and combine these two antennas where I now have amp on uhf only and could use some amp on VHF and could use the other coax line and that amp at home. There are no strong signals in the area or either direction to overdrive an amp.
So since I don't trust the RCA TVPRAMP with the uhf and vhf inputs does anyone have experience with the CM778HD ? Good? Bad/ Indifferent?

[rabbit73]

Originally Posted by kb4

I know this is more complicated and costly than it needs to be but would a setup something like this have a chance of working ?

https://imgur.com/tpRBcPm

The chance of it working is poor but not impossible. It's just another way of combining two UHF antennas aimed in different directions, which doesn't always work. To satisfy your own curiosity, you should try it; you will not be happy until you do.

If I did set up a repeater similar to this would both of the antennas have to be identical ?

No

Is there a certain length of connecting coax to use? and if amp needed would length of coax from receiving repeater need to be same as transmitting repeater?

Coax lengths not critical. If you use an amp for the transmitting antenna, you would have an unlicensed repeater that isn't legal.

Would the signal from the other stations closer to that direction cause a ghosting effect and interfere with reception on this channels or just the strongest signal win out so to speak or would I have to filter out those channels?

It's an interesting idea, but the results of this method of combining are difficult to predict. Custom filters would make it even more complicated.

On somewhat unrelated topic for different location at hunting cabin I have a Winegard 8200 for real channel 5 and 13 VHF low and high band and a different antenna for UHF with amp for another market direction that requires an amp utilizing a/b switch. I was considering the channel master CM778HD amplifier to both amplify and combine these two antennas where I now have amp on uhf only and could use some amp on VHF and could use the other coax line and that amp at home. There are no strong signals in the area or either direction to overdrive an amp.

That might work, but I haven't seen the TVFool signal report.

So since I don't trust the RCA TVPRAMP with the uhf and vhf inputs does anyone have experience with the CM778HD ? Good? Bad/ Indifferent?

I don't trust the RCA TVPRAMP1R either. I bought two new ones in sealed boxes and they both failed; poor quality control. I haven't tried the CM7778HD, but the specs look promising. Have you tried a replacing the A/B switch with a UVSJ?

[kb4]

I may try the repeater idea just to see what happens it wouldn't take long but as much time as I have spent on it lately it will have to wait a while but if it worked it would enable all signals to come down one coax to be distributed to all tvs in house and wouldn't need two amps and two coax runs and combiner of one sort or another. At present use an a/b switch at main tv and watch whatever is available on that antenna on all tv s . I may consider trying a homer or similar device that has two tuners etc on network.

I wouldn't be using an amp for the transmitting antenna for sure.


At the hunting cabin VHF already barely watchable so pretty sure any further db loss such as UVSJ would make it unsuitable without a separate amp on it which is why I was considering utilizing the cm778hd and still have RG6 and current amp to use elsewhere offsetting about 70% of the cost of the cm7778hd.

Whatever I do I will Report on results but now that I can definitely receive WYJJ well and leaves are well on their way out and rain last night and 20 mph wind today with rare pixelation I feel its a good chance I will be able to continue watching it.

Thanks again for everyones help !!

[rabbit73]

Originally Posted by kb4

Whatever I do I will Report on results but now that I can definitely receive WYJJ well and leaves are well on their way out and rain last night and 20 mph wind today with rare pixelation I feel its a good chance I will be able to continue watching it.

Thanks again for everyones help !!

Thank you for the encouraging report on WYJJ. Glad we were able to help.

Best regards,
rabbit

[kb4]

Thanks Nascarken. I am looking at the johansson also but I plan to use it only to combine the VHF portion of the 8200 (don't need any UHF that antenna receives} with the UHF output of a different antenna receiving signal from another direction which would be similar to combining a 91xg with a VHF high and low antenna, not pointing in same direction. I haven't found a johansson amp with a separate VHF and UHF input but I haven't looked through all their models yet

I wish kiltztech made one. I did note that the supposed noise figure on the cm7787hd is 1.5 db on UHF . The RCA PREAMP1R and the CM7778HD are the only ones I have found so far that amplify separate VHF and UHF inputs . I am sure there may be others I haven't discovered yet. I did see a reference to and "old" model cm7777 that apparently had both but was discontinued

[bobsgarage]

Originally Posted by kb4

thanks I will look up that specific model

Yes, let us know what you find.

[rabbit73]

Originally Posted by bobsgarage

Yes, let us know what you find.

There are a lot of different models of the Johansson preamp.
preamplifiers, scroll down:
https://unitrongroup.com/en/products/CAT/AMP/APRE.html

preamplifiers and kits, scroll down:
https://unitrongroup.com/en/products/CAT/AMP/AKIT.html