Made a start on my petal extensions ..

[BM300]

Congratulations on things working out.
About Aluminium solar reflecting paint, you are lucky not to have som much sun in the UK.
The shiny surface could easily burn the plastic cap covering your LNB.
This is common in the middle east among peaple who coated their dish with shiny coat of paint.
It may be a good idea to sandpaper it to take the sine away.
In some areas they use the highly reflective dish for cooking (the LNB is replaced by the pot containing water)

Here is a nice use of unwanted dishes:
_http://www.backyardnature.net/j/solardsh.htm

 

[Vipersan]

Thanks BM ..but worry not ..
The majority of the dish is a matt cream colour ..and whatever I do with the extension wings will be made to match the main dish area as close as possible ..
Already on order ..gelcoat with cream pigment addative..

I have however had another possible change of direction in my thinking ..
Certainly I'm going to try this on the third panel ..
It can be sanded off if unsuccesful ..but I have to try it.
Just ordered 1 roll of adhesive backed aluminium tape ..10 cm x 45 mtrs long ..

Quick back of a cigarette packet calc ..I should need approx 6 mtrs..
I propose to lay this radially onto the sanded smooth wing surface in overlapping strips.
to follow the wing contour.
The aim ..to get a closer smoother ..more accurate finish ...with a thicker more dense reflecting surface .
This too will be painted over to finish in matt cream ..if it works out ..
We shall see ..
pictures will follow of course..
Whatever I choose as the final option ..
Hopefully the Gelcoat will encase the surface and form the final lamination layer.
rgds
VS

..regarding the lack of sun ..
I'd rather spend a lot of time painting the dish ..and have more solar rays on my back ..
;)

 

[Bajasur]

Be careful with the tape. It can delaminate when it gets old and in a year or two you might see problems. Aluminum mosquito screen works well (with about a 1-1.2 mm opening). The resin or gel coat fills in nicely and really locks it on tight. That screen mesh size is good up into the ku band frequencies with no signal loss.

 

[BM300]

Be careful with the tape. It can delaminate when it gets old and in a year or two you might see problems. Aluminum mosquito screen works well (with about a 1-1.2 mm opening). The resin or gel coat fills in nicely and really locks it on tight. That screen mesh size is good up into the ku band frequencies with no signal loss.

Intresting,
About filling in the mesh with resin, I have tried this with an H/H 12 ft. Paraclipse dish but ended uo with a dish that was double its original weight.
The gear motor was crying out for help and was very slow (and yes I had a counter-weight installed).
Had no improvement in the signal quality (may be it was optimal anyway).

 

[Vipersan]

Be careful with the tape. It can delaminate when it gets old and in a year or two you might see problems. Aluminum mosquito screen works well (with about a 1-1.2 mm opening). The resin or gel coat fills in nicely and really locks it on tight. That screen mesh size is good up into the ku band frequencies with no signal loss.

Hi Bajasur ..
You make a good point ..and I had considered the possibility of the adhesive coming adrift ..but assumed this would be down to weathering and heat exposure..
However since the tape would be encased under a cream reflective layer of gelcoat ..
The heat (minimal here in the UK) and weather (rain) would theoretically be unable to penetrate to the tape suface thus it should remain bonded for many years ..
I already have aluminium tape strips running the length of the original dish petal seams to avoid dirt and believe it or not ..moss getting in ..
fitted almost 2 years ago ..and still bonded so tight it wont come off clean if peeled.
And this tape IS exposed to the elements every day.
Like everything else I do ..Its just an experiment ..
If it fails ..I'll just start again with another mad idea.
The beauty of this experiment is that the wings themselves can't fail now they have cured ..and so I can always sand them down to the original surface and start over.
Fibreglass is messy ..smelly and tricky to work till you get used to it ..
..but imo ..is the weapon of choice for amateur dish makers..
rgds to all
VS

 

[Vipersan]

This one photo ..snapped during the very briefest of locks ...has for me made the whole project worthwhile..
..and gives me great hope that when fully optimised ..it will remain locked for longer periods ..
I haven't seen this channel since it went to 7/8 over 12 months ago...
3853 H
tp 22

Jamaican mux
DVB-S 2220-7/8

RE TV
&

TV Jamaica
55 West C band

Here is the pic ..and delivered with a huge grin ..

rgds
VS

..Not sure if its time of day or just freaky reception ..but TVJamaica for the last 10 minutes has given me almost total lock ..and moving images with very occasional freezes..
Whats changed ..
I've refitted the 2 wings I've recently altered the tilt on ..plus painted with the aluminium solar paint ..then backed the commercial scalar plate currently fitted ..off by about 1cm to increase illumination to theoretically include all or part of the wings
Previously I occasionally got signals anywhere between 6 and 6.4 db max..and floating erratically
Now I'm getting signals between 6.2 and ..6.6 db and less erratic..
Oh...I'm sure there's more to come ..this is not a scientific approach ..but 'tis xitin' as Russel would say..
rgds
VS

 

[Vipersan]

..Going for another test ..but this involves a dielectric plate ..so anything can happen ..
Going to use a DOS plate so that the extension beyond the lnb throat of a T plate is less relevant ..
If I can get a signal in excess of 6.5 even for a moment from The Pentagon Channel at 1W (my all time high ever) ..then I know I'm heading in the right direction ..
Probably wont ..and I'll be deflated somewhat ..but I have to try.
rgds
VS

 

[Vipersan]

All signal levels are referenced to the F15s level meter..
..Well ..TPC was the same ..not worse just the same ..but it always was a tricky blighter ..with laws all its own ..
On a positive note though ..
Emanuelle TV @ 20 West broke the 2db barrier ..and touched 2.2 db briefly..
My previous best was 1.9 if I remember correctly..
Also both muxs on 10 East remain in permanent lock now at 11.5 db plus ...the best I ever had there was well above this by at least 1db ..but ..never with a commercial scalar feed..
It certainly feels better all round ..
Much more positive locking borderline stuff..
So I guess it could be just freaky conditions at 55W ..and will monitor over the next day or so ..to see if the signal level is maintained.

VS

 

[Vipersan]

Left the dish overnight pointing at 55W ..
The signal level on JNN was maintained around 6.4 - 6.5 db ..
Left the curtains open which woke me early to ...errr..I believe they call it _sunshine_.
So dragged my aching carcass out of bed ...after checking the signal levels ..
and yes ..still averaging 6.4..
Removed the 3rd wing ready to mod it ..
The signal level only dropped to average 6.3
But no sooner had I moved the gear outside to begin work ..than ..you guessed it ..
It started to rain again.
Rain stopped play ..but the good news ..the signal level is still averaging around 6.3 db ..and stays locked ..
..moving images more than stills..but a bit more eratic in variation on the F15s db scale.
Dish surface currently wet ..but it looks like the 2 modified wings are more than compensating albeit a small amount ...for the inefficiency of the unmodded wings ..
I know its all guesswork ...but it just 'feels' better somehow.
rgds
VS

 

[verwegsateliet]

nice more detail proucts isuse quantities see u jhave hole closed with rubber tried plate back for ku band better wondered if it would be better in front wht do u think.

 

[Vipersan]

nice more detail proucts isuse quantities see u jhave hole closed with rubber tried plate back for ku band better wondered if it would be better in front wht do u think.

Appologies friend ..I'm not really sure what you are asking ..
If you are referring to the dish centre ?
..this is effectively a blind spot on the dish as it is in the illumination shadow of the lnb and feed ..so is actually not used to reflect signal .
Also that is not rubber at the centre ..it is in fact a self leveling camera to check alignment and tree growth/obstacles in the dishes line of sight ..
rgds
VS

 

[Vipersan]

Ok ..here are todays efforts on wing 3 ...
This one has had its tilt angle changed ...plus a new skin of fibre glass tissue and resin to bond the whole thing together ..
Rubbed as smooth as I could get it ..sadly not perfect ...
Then radial strips of 4 inch - high density..alluminium adhesive tape applied ..
I'm going to chance it staying dry and fit it tonight but will be removed again tomorrow for its final layer of cream pigmented Gelcoat..
Here is the wing ..
Looks good so far ..
rgds
VS

 

[Vipersan]

Ok ..here is a pic of wing 3 re-fitted ..
Should be easy to spot ..
The 2 previous wings 1 & 2 have tilt change applied ..but painted with aluminium paint rather than tape strips ..
Also including a close up edge on to show the tiny ammount the wings tilt is changed ..
This should in theory bring me closer at focus to the correct focal length .
rgds
VS

 

[ralphmagno]

hello,
wanted to inquire on this thread. with the extentions in place what are you going to receive. that is not comming in now?
you dish looks like a 2 meter.

 

[Vipersan]

Hi Ralph ..
Its acually nearer 2.2 mtr now ..
As to channels ..
I want to lock channels previously beyond my reach ..
Which I have already done since the wings were fitted.
Also ..borderline Channels that were present but would not lock before ..like the Jamaican mux on 55 West..
I cannot claim it is behaving as a 2.2 mtre..but am fairly confident that the wings are working ..and the dish is behaving like a 2m dish at the very least.
rgds
VS

 

[pride21]

looking good VS be interesting to see after you get the other panels sorted what else you will get.cheers

 

[verwegsateliet]

what i ment i have a ws 180 looks likes one using for ku band wondering why the whole whas closed i closed mine at banck get 1.4snr more on ku wondered if it would make a difference if it is in front instead back also i dont see a a buy list and what about a dummie list of step by step dont see precise how did you trACK OR MESUARED THE WINGS or did you taced of the main dish. thx

 

[Vipersan]

Having now altered the tilt by approx 1cm on 4 wings I was able to measure and get a rough idea of what the new focal distance would be ..

The original dish was re-measured and the various aspects are as follows:-

1.8 mtr (180cm)
Dish depth 25.3 cm
Therefore FD ratio 0.44
Focal distance to lnb 80.04

With the wings added and tilt altered a bit
it makes the dish a small ammount deeper

diameter 219cm
Depth 36.5cm
FD ratio 0.38
Focal distance to lnb 82.13

So by my reconing I'm still 2cm out
How critical this 2cm will be is as yet an unknown quantity ..
So I have a choice to either increase the tilt some more ..with packing wedges
Or work on the assumption that I will not 'effectively' be using the last few cm of the dish for signal gathering.
Comments on this would be helpful and welcome

What it does clearly tell me is that I will have to shift the lnb relative to the scalar feed plate ..and this will always be a compromise.
Don't you just hate it when you get your sums wrong ..even by such a small ammount.
My teacher would have given me a big red X and 'see me' at the bottom of the sheet.
rgds
VS

I've probably asked this before ..but I'll risk repeating myself ..
Should the front or back of the scalar feed be placed at the focal distance ...and the lnb set to the correct fd ratio using the integrated scale _within_ the scalar feed ..
OR
Should the front edge of the LNB be placed the focal length ..and the the scalar feed then be adjusted to the correct FD ratio as shown on the scale.
Something I have taken forgranted in the past ..and just set the lnb and scalar plate roughly at the focus and tweaked for maximum signal on a weak channel ..
Not very scientific ...but since the FD ratio will now change quite dramatically ..I'd like to get to grips with this properly.

 

[Vipersan]

Just to give you a taste of the progress I'm making .
Here's a pic of Christina sporting 2 almost completed wings done with reflecting layer of adhesive aluminium radial strips 4 inches wide ..then encased fully in Cream Gelcoat..
Not totally happy with the colour match ..so I may well give them a final coat of spray paint..
Of which the closest match I can find is 'Ford Ivory' as used on the roofs of landrovers I believe.
So 2 wings painted in aluminium paint but not aluminium tape ...2 in aluminium tape and gelcoated ..and 2 wings as yet untouched and requiring tilt ajustment.
Results are good so far ..but I'm convinced there are more pips to squeeze.
rgds
VS

 

[aceb]

Should the front edge of the LNB be placed the focal length ..and the the scalar feed then be adjusted to the correct FD ratio as shown on the scale

This one although the majority of sites I found while looking for the same information said the FP is just inside the throat of the LNB but only one site gave a distance, about 1/8". I never found a critical or theoretical distance so maybe it's not an exact science?

I've never had the enthusiasm to make the LNB/feed support adjustable other than packing it out on some washers so I'm not sure how much there is to gain from something that has been set up as above.