Replaced Dway LNB with Invacom SNF-041

Status
Please reply by conversation.

snathanb

Supporting Founder
Original poster
Supporting Founder
Feb 26, 2004
2,580
3
DFW
And signal level went down....quality stayed the same.


Spent several hours tweaking... and bottom line, I get lower signal levels from the invacom.

Ironically, it gives me a higher signal level if I am right at the dish, but it drops more over the long cable run to my bedroom where the receiver is located than the old dway one does.

DWAY Signal Level 76% at the dish, 76% in my bedroom
Invacom Signal Level 80% at the dish, 68% in my bedroom (as shown)


Before and after shots are attached.

I took many other shots of the upgrade process, with anticipation of posting a glowing review, but right now I just feel like I threw away $50 on this LNB. It may work fine, but across the arc it has provided little, if any, improvement over the LNB I already had.

The pictures are reversed looking at the post... the picture on the right is "Before" the picture on the left is with the Invacom.
 

Attachments

  • TubeBefore.jpg
    TubeBefore.jpg
    25.5 KB · Views: 241
  • TubeAfter.jpg
    TubeAfter.jpg
    20.7 KB · Views: 267
I think your pictures would still be of value to the members : )

Signal level includes background noise, so when it drops thats a good thing. Signal quality is what it is all about. 1% extra can often mean the difference between a picture and no picture when you are looking for weaker channels. That's where the Invacoms come into their own. (IMO)

Give it a few days, it comes with a 5 year warranty.
 
I noticed when you switch to a Universal, the signal level goes down.

My G10 signal is at 74-75 with a standard LNB (.5), yet when I put the .4 on the signal level goes down to 65-68.

But signal level doesnt mean anything...its QUALITY that matters :) When that goes down after putting the Invacom on, then there is issues
 
My concern is that I get a higher signal and quality level with the invacom when outside at the dish... but it drops from 80S/55Q at the dish to 68S/48 inside the house. When I hook up the old DWAY LNB, I get the same readings inside and out. I understand your point about when switching to a Universal, the signal level going down... and if it was down everywhere, I'd live with it. I just don't understand why it's dropping so much over a 100 ft max cable run.


I have a dual RG6 running from the dish to my bedroom where the box normally lives, and I switched everything over to the other cable, same result.

I'll post the upgrade pics when I'm done playing around the system...
 
Hi! I've been reading this forum for quite some time, and a few weeks ago I made the plunge and got my FTA setup (90cm dish, fortec receiver, motor, etc). Got everything running pretty smoothly and decent reception, with one exception... Transponder 11929V on IA5 (Telstar 5) which only came in at 60% quality on a good clear day. I figured, maybe replacing the LNBF would help (I have a 0.4dB Fortec LNBF). So I got the Invacom 0.3dB LNBF off of eBay somewhere (new), and installed it. Shockingly, I had a similar experience as you had! My signal level dropped about 5% on average (which could be explained by the lower noise floor), but worst of all, my quality on that specific transponder dropped!! From 60% to about 48-49% on a clear day (with frequent breakups in the video!)... Whatever I tried (peaking the dish again, changing cables, eliminating the motor, etc), nothing got my quality to 60% or higher with the Invacom. So I put the Fortec back, and I'm back at 60% quality and rock-solid video (as long as it doesn't rain.. :) ).. Strange and unexpected to say the least!

Robbert
 
welcome robbert :wave

did you rescan the transponder? Only other thing I can think of is the Invacom is a little heavier so maybe the elvation needs to be tweaked :)
 
Thanks Iceberg!

I did rescan the transponder and also adjusted the elevation slightly to peak the signal. When I mounted the LNB I noticed it was heavier and might sag the arm down a little. So thats why I peaked it again at that transponder, but as I said.. No better than 50% quality where the 0.4 dB was doing 60%.. Now I do have to note that this is a very iffy transponder. Moving my motor 0.1 degree causes the signal to drop from 60% to 50-40%.

Unfortunately this transponder carries the Dutch channel (BVN-TV) I got this whole setup for in the first place.. So I guess I'm going to have to stick with my 0.4 dB and a significant rain/cloud fade for now... Just wondering if I should have gotten that 100cm dish instead.. Haha! No way to do that now with my wife already annoyed at the 90cm next to our little DirecTV dish.. ;)
 
robbert

I have a 76cm and a .4 and BVN gets about a 55-60 for me on my Pansat (each receiver's meter may be different).

Bummer that it was doing that...maybe a 100cm is in the works :)
 
"My concern is that I get a higher signal and quality level with the invacom when outside at the dish... but it drops from 80S/55Q at the dish to 68S/48 inside the house. When I hook up the old DWAY LNB, I get the same readings inside and out."

What frequency is this measured on and also what's the local oscillator frequecncy of each LNB and thus the IF frequency of the signal traveling down the cable. Coaxial cables efficency decreases as the frequency of the signal traveling through it increases. It could be that with the Lnvacom LNB the IF frequncy (frequency of the signal traveling down the coaxial cable) on this particluar signal is higher and thus you get more loss in your coaxial cable. This could acount for what your seeing here. I believe this is reffered to as "Line slope" and basically means that higher IF frequencies are attenuated more by long cable runs that lower IF frequencies. The reason your seeing the it on the Invacom may be that the IF frequency on this particluar signal may be higher because the LO frequency of the Invacom may be lower and the IF frequency is = (transponder frequency - LO frequency). It may also be that the old LNB compensated for this and increased gain at higher frequencies.
 
Iceberg,

You're getting 55-60% with a 76cm?!?!? Maybe there is something wrong with my setup, since I have a 90cm I would expect it to be significantly better than a 76cm.. Maybe location/geography has some effect here, but I do have a clear view of the sky from here. (in New Hampshire)

That 100cm sounds like fun, but I don't think my wife will go for that.. ;) If I'd get a 100cm, I'd most certainly want to keep my 90cm as well... And that would mean 3 dishes on the house.. 2 was a stretch, but 3 is probably impossible.. Hahaha!

Thanks for checking for me!

Robbert
 
robbert
Let me check tongiht...I only have a few channels from IA5 logged in (BVN is one) and most of the transponders are between 50-60 (the church ones are at 60...some others are at 50 or lower)
 
Robbert said:
Iceberg,

You're getting 55-60% with a 76cm?!?!? Maybe there is something wrong with my setup, since I have a 90cm I would expect it to be significantly better than a 76cm.. Maybe location/geography has some effect here, but I do have a clear view of the sky from here. (in New Hampshire)

Thanks for checking for me!

Robbert

Jealous much? IA5 is my true south and I pull most of the transponders in great.
 

Attachments

  • BVN.jpg
    BVN.jpg
    47.7 KB · Views: 220
Whoah! Talk about jealous! I guess having IA5 as your true south would help.. For me at 71.2 degrees longitude it's almost 28 degrees to the west.. But for me SBS6 and AMC6 are almost true south.. Yeah! (just wish there was anything good to watch on those, besides the Ohio News Network, which doesn't do me too much good in New Hampshire....) :)
 
I Iowa with a 76cm dish, I'm betting 45-50 on BVN. That's with a ASC321 LNB rated at 0.5.

I bought a BeSat universal LNB rated at .3 off e-bay for $25 including shipping. Considering the price, I wasn't expecting miracles but thought I might get some improvement in quality. Although a few transponders here and there showed a slight increase, most had no improvement or a slight drop in quality.

There was another problem with using the BeSat... when tweeking using DiSEqC 1.2, just a very slight movement would cause it to lose the signal completely. I went back to the old LNB.
 
Status
Please reply by conversation.
***

Users Who Are Viewing This Thread (Total: 1, Members: 0, Guests: 1)

Who Read This Thread (Total Members: 1)