New Lnb changer

[Captain Jack]

Trust/Rimant, if it's a problem making a wheel for 5 LNBs, I am happy to make do with 4. 2x C and 2x Ku/Ka... I would like to eventually get an AV-Comm unit so it's likely to stick out of the back a bit.

I do prefer Trust's wheel as it seems more solid and I would also prefer the motor to be under or just behind the dish. I think if we use lightweight material such as aluminium to support the motor at the back, it won't add much more weight to the overall construction.

Of course, open to many other options too!

 

[Trust]

I'm waiting for the Technisat rotor , thursday i can go on with this project .
Already decided to use a bigger size "spiderhead" (wheel) so the treaded rods are shorter and less flexible .
For the long AV-comm unit , a extra support could be attached to the centre bolt of that spiderhead .
Liked John's option to use the CM side arms , will make some parts to make that possible .

 

[John]

I'm waiting for the Technisat rotor , thursday i can go on with this project .
Already decided to use a bigger size "spiderhead" (wheel) so the treaded rods are shorter and less flexible .
For the long AV-comm unit , a extra support could be attached to the centre bolt of that spiderhead .
Liked John's option to use the CM side arms , will make some parts to make that possible .

... will be interested in the mechanical spec of the Technisat motor Mr Trust when you get it, this "spiderhead" part sounds interesting and intriguing ..... have you got a rough sketch of it you can share with us .
Re: the side arms configuration, i'm really pleased at how solid it has made the whole frontal support system combined with the 100 x 25mm lower support arm as well.

 

[trip82]

Hi everyone, what a nice topic, amazing skills here
Just a question, this lnb changer will work on a prime focus dish?

 

[Captain Jack]

You could probably force it but I don't really see how...

 

[John]

Hi everyone, what a nice topic, amazing skills here
Just a question, this lnb changer will work on a prime focus dish?

.... Very difficult to engineer and to implement on a standard PF dish i would say. The signal obstruction by the various attached lnb's , especially C-band lnb's would be undesirable as well. It's really suited and ideal for off-set type dishes really but still can present some head aches to overcome

 

[Trust]

Visit this afternoon my sister , living in Goch (Germany) to pick up the TechniRotor (Shop did not ship to NL)
Very nice rotor , different size but the specs , motor and circuitboard are the same as Moteck SG series .
AZ corner 150º
Tomorrow I will make it with a new beam to the dish .

 

[RimaNTSS]

speaking about LNB changer on PFA, I think it is more than possible, but construction of changer should be different. And, yes, shadow effect will be greater, unless you do not have antenna > than 3 meters. .
Motors: I think TechniRotor is cheaper, lighter and could be used for changer for offset dish, even it has 150* turning. I think it is still possible to adopt it for 2x C-band and 2xKu-band LNBs.

 

[Analoguesat]

Ive just read this one through from the beginning - and to echo trip82 a few posts back up the thread - ingenious designs, and fantastic engineering

 

[Trust]

speaking about LNB changer on PFA, I think it is more than possible, but construction of changer should be different. And, yes, shadow effect will be greater, unless you do not have antenna > than 3 meters. .
Motors: I think TechniRotor is cheaper, lighter and could be used for changer for offset dish, even it has 150* turning. I think it is still possible to adopt it for 2x C-band and 2xKu-band LNBs.

I'm shure it can!

 

[Archived-1]

Hi everyone, what a nice topic, amazing skills here
Just a question, this lnb changer will work on a prime focus dish?

I would copy this design for a PF dish .
4 Port C/Ku Band Motorized Feed Assembly | Viking Satcom

 

[Archived-1]

Hi, ive just checked one I have for you.

 

[trip82]

And, yes, shadow effect will be greater, unless you do not have antenna > than 3 meters. .

sorry Rima but this sounds a bit confusing to me... my dish is a PF 2.4, so about the shadow effect I'll not have problem, that's your reasoning right??

I would copy this design for a PF dish .
4 Port C/Ku Band Motorized Feed Assembly | Viking Satcom

That it's really nice martin, but it's already hard for me to copy the ideas in this topic, even worse if I try to copy the design on that link lol
but looking at pictures in that link I was questioning me, how this works? I have an idea, maybe it's stupid and completely wrong... all the 4 lnb's use the "central" body of lnb to mirror the signal... when the motor rotates to a correct lnb skew the signal cross to that lnb?

I have a Golden Media GM-50-120, it's really heavy for give a try on my PF dish... I'll think in a way for do it anyway with other motor.

Thank you all for such knowledge here

 

[RimaNTSS]

@trip82 My reasoning was: smaller dish-bigger shadowing effect. In case of LNB-changer shadowing effect could be up to 5 (maybe more, depending of the number of LNBs in changer) times bigger than single LNB makes. 2,4m antenna would also work with LNB-changer, but shadowing effect should be taken into account. And, also, do not forget about total weight that will be concentrated in one place and quiet away from antenna.

 

[Archived-1]

Something like this would be an awesome set-up on Martins 2.4 offset

I don't feel the need to install something like this on it John, I can off set 6 lnb if I wished and the last one inline would still perform better than my 1.8, I will be fitting two pro lnb one C/one KU side by side both of centre when money permits.

 

[trip82]

thanks Rima, my idea is a lnb changer with 3 lnb's max, 2x C 1x KU.

I made a poor design to have an idea... maybe you guys can tell me your opinion

if I go for that I have to alter the feedarms to don't block the lnb front i think

in that design the motor should be installed in bottom of the dish

 

[Archived-1]

That it's really nice martin

Yes its very nice, I am unsure how it works tbh, take a look here this might be an option for you ?, Beavs is very helpful and knows what he is talking about if you need more information .
Channel Master SMC 3.0M PF restoration

 

[RimaNTSS]

I made a poor design to have an idea... maybe you guys can tell me your opinion

I think you are trying to over-complicate things. If I was going to have changer on PFA, I would probably go something like this. Of course, because of big scalar rings, diameter of changer should be bigger.

 

[trip82]

My design is really poor, that's why you think I'm over complicate Rima, otherwise you understand what I try to say is very similar to your image... the change in relation to your image are the position of the arms that hold the lnbs... I try do a better design latter

my bad English doesn't help too, sorry for that.

 

[RimaNTSS]

@trip82 do not worry about your language, you are well understood (at least by another not native speaker like me) . There is my visualisation how I am going to mount changer to the dish. Imagine that what I circled red is lower feedarm, so under it threaded rod will be located and turned by motor on hinges (circled green). This is just an idea. If lower feedarm is long than hinges could be 3 or even more.
Hope my broken tongue is understood.