Dish Flop on C band dish

[RimaNTSS]

Still no pictures?! Attach actuator in proper places of the mount and you will not have any flopping issues. 70* span it is more than easy to achieve without any danger for flopping.

 

[Costactc]

I agree. My c band arc used to be 11-127w before I attached the actuator on the opposite side for sats 131-139w.

 

[rancerote]

I'm building something to prevent flop my dish, in few days I'll post some pictures when its ready

 

[wium78]

That is good news i am waiting to see the pictures.

 

[RimaNTSS]

That is good news i am waiting to see the pictures.

Same as we are waiting your pictures , as it was your issue of dish flopping, but no any pictures. BTW, some ideas where offered already, but seems you did not use any of them, and after at least 3 months you still have same same flopping issue and no progress. Do you need more ideas or maybe it is time to do some hardware work on your antenna?

 

[wium78]

See my seperate posting under Dish Flop on Thursday 7.36pm.Why crucify me i am 79 years old.

 

[RimaNTSS]

Not crucifying at all, but I clearly see that your dish flopping issue is purely hardware related. Or you adjust actuator properly, or you change its end-switches accordingly. I really do not see anymore ways how to get rid of flopping of your dish. And, really, picture of your installation would help a lot.

 

[Archived-1]

Out of interest Wium what actuator are you using please,

 

[Lazarus]

Mod. Note: Ok, I think it's time to merge the two related Threads on this, as I fear confusion may reign otherwise.

Give me a minute ................... Done

 

[wium78]

Martin-f, i have several actuators in bits and pieces and they vary from Drake,Venture,Echostar etc.As far as i am concerned they are made in the same Chinese factory with a different brand name.I lived in Zimbabwe for many years and in the 80,s i had a 6M dish.Over the years i collected some discarded actuators which i brought down with me when i left in 2002.Big dishes are no longer used in Zimbabwe and South Africa and it is only a few of us that do it as a hobby.Over the years i had to cannibalise the actuators for parts.For a reed switch i use the sensor that is fitted to a door, in a house alarm system
My problem could well be hardware as i have never worried about setting limit swiches or the limits of the positioner.Also possibly a faulty retraction or extension limit switch in the actuator.Be that as it may several people have written about flopping and i am not sure whether one can always put it down to a hardware problem.

 

[Archived-1]

Hi Wium, I don't think you will get any better advice than post 9, are you missing out on satellites due to the flop ?, if not just set limits inside the actuator, no need to make stops just move the cogs.

https://www.satellites.co.uk/forums/threads/dish-flop-on-c-band-dish.163776/#post-911414

 

[Manikm909]

I've made several adjustable mechanical stops. With them I was able to even remove actuator from antenna at all and at the same time still be tuned to far-East or far-West satellite in my arc. On attached pictures my most Eastern satellite was 90*E.

great idea @RimaNTSS - i will do something like that, on extreme west - cant remember if it was my 24inch jack or 36inch jack in use which damaged my old 1.8 dish due to dish flop....simple idea, but effective.

i beleive it happens when the jack arm is very much extended, and the dish is at so much of an angle, gravity and the weight of the dish equals failure in many possible ways.

 

[a33]

i beleive it happens when the jack arm is very much extended, and the dish is at so much of an angle, gravity and the weight of the dish equals failure in many possible ways.

How I understand it, is that flopping occurs when the actuator goes over the rotation axis.
So indeed, for instance, when extended (and near the rotation axis), and the dish weight is pulling the actuator over the axis.

It can also happen at the retracted side, for instance when the legs of your actuator triangle design are rather unequal in length, and one of the legs is pushed the wrong way.

So the actuator triangle fixing points, in relation to the arc width you want to receive, are important.

Also notice the text "The bigger C is, the more the risk of flopping is reduced" in this post:

Just Sharing This - My Channel Master 1.8 project.

as soon as the weather improves (today I have a very cold fog) I will take some pictures to show how my actuator is set. I made a solid clamp to let the actuator move away from the polar axis when it goes east (the cylinder is on the west side) when the actuator is fully retracted (west) it is...

satellites.co.uk

That could help as well!

Greetz,
A33