Couldn't resist a new dish

Channel Hopper said:
That -type of -motor really needs to be in constant compression.
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Er..... Huh? You mean pushing rather than pulling?

I agree but it was very tricky to do as it would have to be done from the bottom and there are lots of things in the way...

Maybe will re-engineer it one day but it will do for now.
 
It will be fine. "Professional" mounts I saw use exactly this arrangement and on much larger dishes.

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The dish is up.... painted green and all seems OK. Haven't yet connected it as I need some lunch! Pictures later.
 
OK, it's up! But a disaster... the dish is warped. I couldn't get any sort of usable signal out of it - nowhere near my 1.2m Channel Master and more of a performance of a 1m dish. I thought it was the paint but I doubt it since I used the same type on the CM and it's fine.

The mechanicals are fine but do need to unwarp the thing... will open a new thread for that.
 

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Why not put a 85 penta back up CJ at high level ? you appear to have picked more sats up from that than your 1.2 CM in the past.
 
Shouldn't be difficult to straighten out. Have you got a large patio window on your house ?
 
martin-f said:
Why not put a 85 penta back up CJ at high level ? you appear to have picked more sats up from that than your 1.2 CM in the past.
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Indeed. At my old flat, I had far more interesting satellites on the Penta than the current CM... but C band on the western sats is what I am after now.

Channel Hopper said:
Shouldn't be difficult to straighten out. Have you got a large patio window on your house ?
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I have large patio doors... Not sure if they are wide enough for the dish.. need to measure.
 
Captain Jack said:
OK, it's up! But a disaster... the dish is warped. I couldn't get any sort of usable signal out of it - nowhere near my 1.2m Channel Master and more of a performance of a 1m dish. I thought it was the paint but I doubt it since I used the same type on the CM and it's fine.

The mechanicals are fine but do need to unwarp the thing... will open a new thread for that.
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Ouch! And then after all that work on the mount...
Have you, erh, strung (must be the right tense) the dish to see how much we're talking about?
(And just to be irritating, I never had that sort of problem with the CMs. Steel and Alu is great, but second hand - you never know...)
Anyway, hope you get it all, erh, straightened out (is probably the right term)!

Edit: Ah, just saw your other thread. But not much I can add it seems ;)
 
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Yes, I strung it - check my other thread - there's about a 1-1.5cm gap. But I am hopeful...

CM dishes are the bees' knees. I have 3 and all are in top shape. As they should be, being fibreglass.
 
Captain Jack said:
Yes, I strung it - check my other thread - there's about a 1-1.5cm gap. But I am hopeful...

CM dishes are the bees' knees. I have 3 and all are in top shape. As they should be, being fibreglass.
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Yup. Have 4 myself now. (Bl**dy heavy, though?!)
One of the CM180 have taken some beating, though. Clear evidence of cracks in the edge in three places, but also plastic bits glued on to strengthen the cracked bits (applied before I got my hands on it). Not seen that before... But it still retaines it shape!
Been oggling a couple of 2.4s lately. though I struggle to justify one - why would I need it (and worse - where would I put it???)

Anyway - good luck with the Gibby. I think our, erhm, hobby is very much about making the most of the hand you're dealt.
 
Success! I took the dish inside into the living room and strung it with 6 pieces of string. There was a massive gap in the middle between the highest and lowest one. So then I pushed the sides of the dish fairly firmly until all the strings came together. This took quite a while to work out which part of the dish was warped.

After getting it as good as I could, I turned it face down and noticed there were some small gaps still on some sides of the dish (not the whole dish was flush with the floor). So I put some weight (washed laundry!) on the sides of the dish that had a gap and some more weight on top so that the whole dish was flush and left it for an hour.

Then I checked it again face up and the strings were close but not perfect. I decided to put it back up on the mount and... result! Getting between 5% and 15% more signal on the Vu+ Uno's SNR scale than I did with the Channel Master. Need to tweak the LNB still and try to bring the strings closer together with the dish in situ... but getting there!
 
Just been out again and the strings cannot be any closer. Squeezed out maybe 0.1dB more but that's as much as the dish/LNB has to give. Still, I am happy as I am getting more usable signal than I did with the Channel Master.

Will be getting my multi-LNB bracket today (according to DPD), so will keep you all posted.
 
What a PITA... got the new multi-bracket for adding an adjacent C band LNB and with the bracket on, I simply couldn't match the signal on Ku against the Gibby's single feed bracket - the signal was easily 1dB down. Spent an hour fiddling with the rail holding bracket, which was making the whole thing slant off-centre. It wasn't set up properly to start with.

Got within 0.2dB with the multi-bracket and then I gave up as it's cold outside! Will fiddle more tomorrow...

I did stick the C-Band LNB 0n and it shines... signals are around 2dB up on what I was getting with the Channel Master and that was just plonked on without any fine tuning. Just scanning 40.5W and I am already seeing channels I've never seen before... Watch this space.
 
CJ! Can not you do something like this? That is cheap galvanized (probably also available INOX :rolleyes:), but in result it is possible to adjust LNBs very independently and precisely. easyfeed (Medium).webp
 
I could but I bought an apparently genuine Gibertini bracket to save me the hassle. Looks like it's more hassle than it's worth so far... will see what I can muster up tomorrow.
 
Here's my blind scan result from 40.5W - getting 20 more TPs than I did with the CM.
 

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Alright ... it's more or less finished. Tried to fine tune it just now but it's very difficult with the changing clouds and a fickle Astra 4A transponder. Should be sunny later so will try and fine tune it slightly later, though I doubt I will gain much more. I am off about 0.3dB over what I had yesterday in fine weather on the same transponder. Also, when I put the C band LNB on the bracket, the LNB arm leans down very slightly, throwing the alignment off...

The dish seems to be straighter than ever as there are no gaps at all between the strings. Perhaps it straightened itself out even more once it was up?

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Very happy with my declination adjustment mechanism. It all feels very solid and the small jack has no problems driving the dish.

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Anyway, here are the final pictures.... the only thing that is likely to change is the addition of a linear C band LNB on the other side.

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