does fibo 90 got a side feed support arms

Well spotted! Usually all 90 Gregorians (Fibo, Philips, Delta Star.... maybe some others) come without support arms. In fact, I did not see any real picture of 90cm dish with support arms, only this drawing.
 
My 90cm Fibo, which is not up at the mo, does not have side support arms, yet someone else I know has one that has them
 
Is It same subreflector for fibo 90 and 120 with difference that 120 got side support arms
 
120cm dish has subreflector with 2 ears and it is slightly bigger (about 5mm wider and 5mm taller) than subreflector used on 90cm dishes. However, some 90cm dishes were equipped with subreflector with ears. We only can say that sub#1 is slightly bigger than sub#2 and it has ears for additional support arms. We also can weight them and observe some difference. Color also could be different. :-rofl2 But, unfortunately, we can not say exact parameters of those sub-reflectors, there are several very important ones, but very hard to measure them, not even calculate.
 
You could make some if you want to make sure the lnb arm doesn't move about in windy weather?
 
Folks! What has just happened!!! One chap in Latvia bought second-hand FIBO dish. I think it is very vintage as 90cm dish has support arms. TBH I did not see such a dishes before! He got it for 25 EUR. No feedhorn, but, anyway. Very nice catch. post-100318-0-21193100-1433360343.webp
 
Almost looks like the sub-reflector is oversized... say from the 120 version.
 
No, it is a right sized sub-reflector i think original, just there are 90 written on them above FIBO.
 
I would like to welcome user @RS900 here , as it is his first post. Welcome Uldis! And he is the one who recently got old Fibo90. I hope to see from you great renovation project of his antenna.
 
RimaNTSS, thank you for your welcome. At the beginning, i need understand myself some basis of physics for missed part (feedhorn) to renovate, and then try to build. Now things are new and interesting for me, will see how and when project are finished. I hope Fibo will return with new self-made feedhorn.
 
There is picture of Fibo feedhorn @RS900 fabricated IMG_20150711_150049 (Custom).webp , and as far as I know he is doing well in attaching non-fibo motor to polar-mount IMG_0302 (Custom).webp . I wish him good luck in this complicated endeavor.
 
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He chose this motor. I can not explain how he is going to operate it, but seems that he knows what he is doing.
 

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RimaNTSS said:
He chose this motor. I can not explain how he is going to operate it, but seems that he knows what he is doing.
Click to expand...
Thats a simple DC motor with brushes an no no rotation feedback .
I hope he's keeping us informed .
 
Now a 95% of mechanical part for Fibo polar mount are complete. Here some pictures, how it looks, possition/angle sensor 13 bit absolute encoder and two end switches. Idea was to fix encoder code to controller for polar mount end positions, calculate midpoint - south after that make some movement to nearest satellite in my case 23.5E for dish adjustments. In this case polar mount mid will be adjusted strongly on S, in theory and all others should come automatically. Next step, controller programming and tests. There are some photo fixes for today:
160316_1.webp 160316_2.webp
 
Looks great !!
With such system it would be possible to control more accurate a actuator driven polarmount .
Even Usals if the encoder provides 39 pulses/ degree
 
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