Strange phenomenon reception Astra 2A

davidcmadrid

davidcmadrid

Member
My Satellite Setup
40cm offset 19e, 1.5m 28e 1.2 M motor vu+
My Location
Madrid Spain
Hi,

I was hoping somebody might have some hint as to why on two different dishes my reciever reports the same signal strenght for 12382 H on Astra 2a . On my 1.2m motorized I get 7db SNR and on my 1.55m fixed i get 7db SNR ( or 42% quality ). I thought at first perhaps my disecq was not switching or something like that however testing on 11023h ( 2F ) i get the expected signal strenght difference. Its " odd " but being inexperienced I cant account for it. Any thoughts ? Can a diseqc fail to switch on certain frequencies ? Im at a bit of a loss to account for it.

Update:

The only difference between dish 1 and 2 is the lnbs. The small motorized dish has the black ultra and the 1.55 has the black eco. Could it be the response of the Eco is very poor cerca 12382 relative to its performance at 11023h effectively eating up the extra db from the larger dish size ?
 
More likely to be related to the metering characteristics of the Receiver, I should have thought. Most are neither accurate nor precise and are to be treated as indicative only.
 
You think the metering charecterstics can be affected on the basis of whats connected or a disecq switch ( both dishes run through a diseqc) ? I realise im thinking aloud now , i dont have experience of differing LNBs and how much they can alter things but to me the cheap ( five quid ) black eco could be the culprit ( ??? ) Is it fair to say that different lnbs can have dramatically differing responses ( gain / noise ) at different frequencies ..remembering that everything behaves as one would expect at 11023ghz


11023h - 2F UK Spot
1.2m : Black Ultra ; Motorized ( DG280 )
54% SNR

1.6 x 1.55 LTE , Black Eco
70% SNR

12382 H - 2A North Beam

1.2m Black Ultra ; Motorized ( DG280 )
42% SNR

1.6m LTE , Black Eco
41-42% SNR

the vu+ uno pixelates below 30%SNR
 
LNVB's all have differing characteristics of how they handle signals and this will change across the frequency spectrum. You may have a particularly deaf on at one particular frequency - easy to find out - swap them over.
 
That's very true - I've had a couple with very low gain around 12.5 GHz.
 
for me got low signal 4.7 c.n with 4.5m
signal be strong at evening near 5.1 c.n
with 4.5m
 
Off topic, why did you bother putting up a 1.5m dish if you are just going to use an Eco LNB? I was looking for a cheap LNB when I set up the T90 and I bought 10 Eco's (about 2€ each if I remember right). Anyway, long story short, I threw the lot in the dustbin.
 
Huevos thats a good question and there is no good answer , my intention had been to put it on the motorized ( which i bought as an afterthought as really the only other sat im interested in is 19.2e ) and the installer stuck it on the bigger dish in my absense so my motorized has the black ultra. I didnt realize it was so duff untill I started comparing the two dishes in detail.
 
Back
Top