poor LNBs

[brian32]

I have 2 old direct tv 18" dishes from past and I am trying to get back in the sats with dish, so I hooked them up about a month ago and had about a 63% on both 110 and 119, there is no trees around or buildings to block those sats and picture was ok.

Then about 1 or 2 weeks ago I had a very choppy picture so I checked the signal strenght and is now down to 40 - 50, I haven't done anything to the wires or dishes or lnbs since I first put them up.

I checked te lnbs and dishes and nothing is looks wrong with them, so I tried re-alining the dishes and can't get a better signal.

So I was wondering is it possilbe that the LNBS are no longer good and I have to get some new ones or just a back cable or receiver (Viewsat Ultra with windows emu).

thank you

[Terryl]

Some LNB's will last 10 to 15 years if the weather conditions are not that harsh.


However the same can't be said about coax, it can get brittle in the sun and the jacket can crack, this can let in moisture, water is a no no for coax.

Also if it is the cheap stuff, the center conductor can rust, (it's copper plated steel) this will affect the signal.

Is the "S" reading 40 to 50? Or are you looking a the "Q"?


And if the LNB's are the old type legacy's the coax may not be able to deliver enough DC voltage to run the old style LNB's.

I would check the coax, see what is printed on the jacket, it should be rated to 2.5 GHz or better, and be RG-6.


Also you said you had two dishes, are you using a switch to go between the two LNB's, if so have you checked it to see if it's working correctly.

[brian32]

I checked the cable is it say 2300 mHz, The cable outside looks good no cracks or cuts. I installed new compression end on all the RG6.

I do have a sw21 switch and i have taken te switch out and run a attached the receiver to the RG6 from the dish only and about the same, I borrowed a buddy of mind sw21 switch (which his strenght is about 90) and put it on and now the S - is about 50 - 55, it doesn't bounce as much as before so I am not sure.

I am not sure what type of LNBs they are there is no name on them.

[Terryl]

Can you get a good closeup photo of them and post it to this thread?

[Hunter11]

Older lnb's do "Drift" a sure fired method to test this is to replace your lnb with a new one. If it's not the lnb which it very well may be, then you will have a spare and you can eliminate the bad lnb from your process of elimination. Your testing will need to continue.

[Hunter11]

If you can't get a pic and post it then Google lnb types and copy and paste the one it looks like, here is a link for example:


http://www.google.ca/search?hl=en&gs_nf=1&cp=12&gs_id=1u&xhr=t&q=direct+tv+lnb&pq=direct+tv+ln&bav=on.2,or.r_gc.r_pw.r_qf.,cf.osb&biw=914&bih=589&bs=1&wrapid=tljp133169765657225&um=1&ie=UTF-8&tbm=isch&source=og&sa=N&tab=wi&ei=A-tfT7_NIsOBOpHE6NwH

[brian32]

I di go out and buy an LNB and installed it on 110 and signal is up to 73%, and around the same for 119, so I think the next thing I will do is re-run a couple of new RG6 lines and see if its better. or do you think its fine the way it is right now. I would just like to get this set up the correc way the first time, I really don't want to keep going back up on the roof every couple of months when I should have done it right the first time.

[jedi]

What type of receiver are you using?

If you are using a receiver like a DreamBox - you can't use an SW-21 switch you'll need a DiSEqC switch.

Have you tried taking out the SW-21 switch and going directly to the LNB and then your receiver?

Are there any connectors in between your dish and your receiver?
Is any part of your RG-6 cable underground - if so it can wick up water if there is any nick in it.

Are you sure the LNB configuration settings are OK - like 11250 for the LOF/H:?

[Terryl]

I di go out and buy an LNB and installed it on 110 and signal is up to 73%, and around the same for 119, so I think the next thing I will do is re-run a couple of new RG6 lines and see if its better. or do you think its fine the way it is right now. I would just like to get this set up the correc way the first time, I really don't want to keep going back up on the roof every couple of months when I should have done it right the first time.

Get some RG-6 quad with the pure copper center conductor, it is the lowest loss coax you can get without going to RG-11.

Also make sure it's rated to 2.5 GHz or better.

You can tell if it's the cheap copper plated steel by using a small magnet, if it sticks to the center conductor it's the copper plated steel, then it's the cheap stuff.

[Hunter11]

I di go out and buy an LNB and installed it on 110 and signal is up to 73%, and around the same for 119, so I think the next thing I will do is re-run a couple of new RG6 lines and see if its better. or do you think its fine the way it is right now. I would just like to get this set up the correc way the first time, I really don't want to keep going back up on the roof every couple of months when I should have done it right the first time.

73% on both seems to be adequate for any model receiver. the way to test for a better quality signal is to find the Transponder with the lowest quality signal and tweak from there, problem is when and if you are using 1 dish for both sats is when you improve the signal for one you lose on the other. I would leave well enough alone as far as tweaking the dish and concentrate on upgrading some hardware as suggested. Always have your receiver powered off when connecting or disconnecting any cables, you will be sure to blow your switches if you don't.There is up to 18 volts flowing from receiver to lnb and the switches are sensitive to voltage spikes. All of this you probably know but others reading this can take note as well. Once your dish is in position take a black magic marker and mark the dish that's attached to the mast so they will line up, it is a quick reference to realigning your dish if and when necessary. You will thank me if you need to do this in the dead of winter. lol. Also write down your other coordinates and skew on a piece of paper and park it under your receiver or some other obvious safe place.

[brian32]

Thank you for that great information, i never though about writting it down, I do know about marking the dish cause I did that one winter when it was it was not fun, though I would quickly tweet it and never got it back till spring. As for the hardware upgrade, I am going to talk to the cheif (wife) and see if I can upgrade my stuff and maybe get HD, which I think she might go for that for her movies and that. hehehehe.

Also I will have to look for an IKS provider, and recommandations? I know I should ask in the other rooms.

Thank you for all your help and you might see me asking more questions when I get new hardware. :)))