Advice needed please

Hi -
All looks pretty much ok to me ... on my offset dish the l.n.b prefers to point a little left of centre ... the plate will not need to go any further in than you have it .... sometimes it works better not so far in ... 40.5 west maybe not the best sat to initially try with on a "smaller" dish 20 east is much stronger and will give results from some transponders on as small as 1 metre .. i would get something there first and then maximize / fine tune before going elsewhere ....
regards ..
 

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gap30,

The dielectric plate looks to be located OK in the LNB. There is no need to force it down to the bottom of the grooves.

Just a suggestion, you could try the C band LNB at the centre point of the LNB arm so that you know it is getting the peak focused signal from the dish. If you took the LNB arm off with the dish sighted on 0.8 West then the C band LNB needs to go back on the arm with the two probes at 9 o'clock and 6 0'clock. This should automatically align the dielectric plate at 7:30 and 01:30

Is there a degree scale on the end of the LNB? If there is then for 0.8W, the 0 mark on the scale should be at 12 o'clock or 6 o'clock depending upon how the degree scale is positioned relative to the probes. In my limited personal experience, C band can be quite forgiving re the polarisation skew, the signal does not fall off a cliff if the polariation skew is not perfect.

Lastly, make sure that you have set the LNB type and LO correctly in your satellite receiver for C band on the satellite you wish to scan.
It might be useful to try a scan with something like EBS Pro on a PC, this might be able to lock onto something that will allow you to delve deeper?

As a side note, you will not be able to get a lock for the C band ESPN signal from 40.5 West (3980L, SR 21600), a signal that you indicated earlier in the topic was of interest to you. This signal is not within the scope of a 1.5 metre dish from a UK location as far as I am aware?


Rgds
 
Setting up the l.n.b. and feed and plate positions for best signal can be a bit fickle ... and may vary quite a bit with different types and sizes of dish ... most of my tinkering has been on channel master offsets of various sizes ... pity your setup is not at ground level , as it can take quite a bit of fiddling around initially to get the hang of C band signals ..
cheers ... :)
 
no joy can anyone recommend a c band lnb and where to get it from

buy cheap buy twice
 
@gap30 I think any C-band LNB will perform not so well if you put it in the vertical multifeed like in your post #64. As you know, the maximum performance will be achieved when LNB's Phase center is co-located with antenna's Focal point. Buy some LNB from Russia, I think they have good ones.
 
RimaNTSS said:
@gap30 I think any C-band LNB will perform not so well if you put it in the vertical multifeed like in your post #64. As you know, the maximum performance will be achieved when LNB's Phase center is co-located with antenna's Focal point. Buy some LNB from Russia, I think they have good ones.
Click to expand...

Hi can you post a link please
 
Must say @gap30 .. Its beginning to look like you could have a dud l.n.b. :(
Even the hong kong cheapo one i,v tried should see something at 20 east - even off centre on a 1.5 dish .. be happy to test your l.n.b on one of my dishes if you want to post it to me ..
regards ....
 
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On some off set dishes (LNB mounting arm at the bottom of the dish) I have found that any "C" band LNB with scalar ring needs to be at the main focal point to work well, offset like it is (on top of a second LNB, or to one side) will cause a significant drop in signal, especially on "C" band if the dish was originally designed for "kU" band.
 
nelson_b said:
Must say @gap30 .. Its beginning to look like you could have a dud l.n.b. :(
Even the hong kong cheapo one i,v tried should see something at 20 east - even off centre on a 1.5 dish .. be happy to test your l.n.b on one of my dishes if you want to post it to me ..
regards ....
Click to expand...

I might take you up on that offer
 
Terryl said:
On some off set dishes (LNB mounting arm at the bottom of the dish) I have found that any "C" band LNB with scalar ring needs to be at the main focal point to work well, offset like it is (on top of a second LNB, or to one side) will cause a significant drop in signal, especially on "C" band if the dish was originally designed for "kU" band.
Click to expand...

1.5m gibby
 
gap30 said:
I might take you up on that offer
Click to expand...

Ok .. Not the best time of year for using the post service :( .. and although i,m in the North west - i,m 75 miles away from Liverpool- so probably out of range for you to bring it to me ... but happy to do either..
cheers .
 
I just need something decent that will arrive quick

Or has anyone got anything they want to sell and can post tomorrow
 
I don,t have anything to part with i,m afraid ... the ones i have here are either in use/needed or have been butchered for experiments ..
cant see any u.k. sellers on e.bay currently ... there were quite a few selling the Titanium p.l.l. ones (ok- but nothing special) a while ago ... even the very cheap hong kong ones have vanished :(

edit - @gap30 .... just seen some of these -- CB-01 9.75/10.6 Universal Ku-Band Twin LNBF High Gain Dual Output Twin LNBF BC | eBay
 
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I have some C-band stuff. #1 is brand new which I did not even try. The rest is used and I have no idea how they perform.
 

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gap30,

Have you tried placing the C Band LNB at the central position (focal point of the dish) in place of the Ku band LNB?

If you have the LNB at the central position as though it was the only LNB on the dish and your satellite receiver is configured for C band on the satelite you are scanning then you should get something from 20W.


Rgds
 
gap30 said:
I just need something decent that will arrive quick

Or has anyone got anything they want to sell and can post tomorrow
Click to expand...

I have a spare Zinwell LNB I could post out tomorrow.

It's a wide band unit, bought as a bulk purchase in February/March, Moonbase made the order initially.

C Band Dual Polarity LNBF for Satellite TV Dish ZINWELL LNB | eBay

I collected it from Redhill so it owes me about £45 plus whatever it needs to get to you on fast post.
Pm me if you are unable to sort out what you already have
 
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