Advice needed please

[moonbase]

Looking at the pic, ... i think he is just by-passing that switch at the moment to get himself a direct feed off either one of the lnb's down to his receiver position

Yes, thats what I thought but asked the question just to make sure. It looks like it is the Ku band LNB that is connected re the picture from 0.8 West.

 

[moonbase]

gap30,

I have attached below a C band scan of 40.5W (SES 6) from this morning. It might give you a guide as to what signals are within the scope of a 1.5m dish for the satellite you are interested in? I used an old 1.5m Precision dish (f/d = 0.36) that has a few minor dings in it, however, its in generally good shape and passes a string test OK. The scan was done using a Titanium single output C band LNB and a Technomate TM-5402 (M3) receiver.

I did not spend a great deal of time adjusting the LNB and scalar so you should probably be able to achieve higher signal levels if your Gibertini 1.5m is in perfect shape and you fine tune the LNB focal distance and the scalar position. One thing I did notice was that there was no difference in signal level with the scalar at the index marks for a 0.36 f/d dish or a 0.38 f/d dish. However, with the scalar at the index mark for a 0.4 f/d dish the signal dropped marginally. Without any scalar at all the signal dropped by 3%, indicating that the presence of the scalar did improve the signal.

Rgds

 

[moonbase]

gap30,

Attached below is an alternative list of my 40.5W C band scan result, summarised by transponders. I am missing quite a lot of the frequencies that are available in C band from 40.5W due to being a small dish man. The "Big Dish Men" with their fine tuned large antenna would get a lot more transponders.


Rgds

 

[gap30]

I cannot get a sniff off the c band lnb, I have the lnb more or less pointing directly at the dish with the plate inserted straight ie top to bottom

I am trying to scan 3980L 21600 8psk 3/4 on 40.5w

Have I got the plate in the right way? I have not put any skew on the lnb just as in the pictures

Not even a whimper of a signal

Ku signals are booming, this is with the C band lnb connected directly

 

[Channel Hopper]

How many degrees off is the second LNB ?.

Are you moving the dish in the right direction ?

Putting one above the other removes the offset error, with the elevation motor doing all the work of peaking.

But you already knew that.

 

[gap30]

Well I am moving up to 25 'clicks' west on positioner

Plus I dont have full control on the linear positioner just yet, just had a couple of metres of cable on it for the initial ku setup

Plan to run a cable in shortly

 

[John]

Not too sure if you have this bit of a guide from Titanium Satellite re: installation.
The strongest signal for me on LHC is 3639 L @ 15.7dB on a 2.2mtr which might assist you to get in the ball park.

 

[nelson_b]

Hi -
Receiver L.nb. configuration settings all correct ? .... l.n.b. frequency 5.150 ...
Forgetting to switch them back from k/u is something i " still" do after many years of tinkering ... l.o.l.

 

[gap30]

So if i read that correctly take my dish to 0.8w (which is my zero) and rotate till the '0' lines up square with the dish

 

[gap30]

Hi -
Receiver L.nb. configuration settings all correct ? .... l.n.b. frequency 5.150 ...
Forgetting to switch them back from k/u is something i " still" do after many years of tinkering ... l.o.l.

I am the original dozy git trust me

I still chuckle about my first dish I set up, hopefully it will be the case in 18 months regards setting up my first 'crappy' C band lnb

 

[moonbase]

...Have I got the plate in the right way...

If you look into the throat of the LNB the plate needs to be located so that it bisects the two probes. If your dish is tracking the arc correctly, as far as I am aware, there should be no need to make any additional adjustment for polarisation skew. The declination offset angle you setup when installing your dish should skew the dish automatically.

The signal you are looking for (3980 L, 8PSK, 3/4) requres a signal level of approximately 7.9db to get a lock


Rgds

 

[moonbase]

gap30,

I could not get a whisper from the signal that you are interested in from 40.5W using a 1.5 metre prime focus dish (3980 L, SR 21600, 8PSK, FEC 3/4).

It's probably worth noting that the scalar and feed support arms cast a shadow on a prime focus dish acting to reduce the available surface area for signal reception. Your Gibertini 1.5 metre dish with the offset focus does not experience this effect so you can probably expect to get slightly higher signal levels than I am getting subject to your dish being in good shape.

There are a few forum members with dishes of 1.8m and larger with C band capability. It might be interesting to see what signal levels the "Big Dish Men" get for your signal of interest?
I have attached below the EBS Pro scan result I got from 40.5W.


Rgds

 

[gap30]

To be honest I am a bit puzzled as what to try at the moment being new to C band

I am hoping its just an error on my part somewhere

Is there an easier satellite to scan for? just so I can know i am there or thereabouts?

Might try putting dish back to zero tomorrow and add some skew

Its just a bit awkward to work on, its pretty high and the roof is very steep (plus clambering around the dish on icy roofs lol)

Just need a bit of luck/inspiration right now

 

[TJExcalibur]

Do a Google for a Satfinder V8. Cost you around £50 but will make it all loads easier. I tried one at a mates house and have one coming as a pressie next week.

 

[nelson_b]

To be honest I am a bit puzzled as what to try at the moment being new to C band

I am hoping its just an error on my part somewhere

Is there an easier satellite to scan for? just so I can know i am there or thereabouts?

Might try putting dish back to zero tomorrow and add some skew

Its just a bit awkward to work on, its pretty high and the roof is very steep (plus clambering around the dish on icy roofs lol)

Just need a bit of luck/inspiration right now

Hi -
20 East is where i generally start with a new setup to get initial signal readings ..
3935 L 27500 and 3975 L 27500 are strong signals
Take care on those roofs this time of year .......

 

[John]

Hi -
20 East is where i generally start with a new setup to get initial signal readings ..
3935 L 27500 and 3975 L 27500 are strong signals
Take care on those roofs this time of year .......

+1 re: the safety aspect, very risky this time of year. Could you borrow a crawler to get up to the lnb position and rope the ladder & crawler to the gutter ?.
Personally i would install the Cband & Ku lnb's piggy back as mentioned before by CH with the Cband at focus to get maximum C-band performance out of a dish that's really on the small side and put the Ku above but there is quite a lot of work involved to do this and is not really the best weather for it. I should hate to hear you have had an accident, a fall from that height can be fatal .

 

[gap30]

I have a cat ladder problem is its on the outrigger so its a peak looking at it square

Plus I did not invest too much into the C band in case it didnt work

It would be easy for me to unscrew the 'boom' lnb arm whatever you call it from underneath its only two screws (plus supporting arms) rather than get on the roof

Ku side of things is spot on, just a bit of trial and error with this - prefer this to be honest better to be thrown in at the deep end and work it out

 

[moonbase]

gap30,

Check out post 80 on page 4 of the forum topic link pasted below. It shows a picture of how "Captain Jack" attached a C band LNB unit directly above a Ku band LNB on an offset focus dish.

Just Sharing This - AV-Comm Polariser + Zinwell lnbf


Rgds

 

[gap30]

Right just taken the lnb arm off to save getting on the roof

Here are some pictures of the lnb, is there anything obvious to you guys that i have missed?

One thing I did notice is there is a ridge where the plate slides down I cannot get it to go all of the way down the ridge, does this matter? If so can i tap it with a hammer (gently)

I can try and get a better shot inside the lnb if needed, there is a yellow and red probe

 

[gap30]