Александр, что имеется ввиду под модернизацией управления скоростью? Аппаратно или программно, не понял по ссылке.
Эдуард , привожу полный текст письма от SM3LBN :
Hello Alex
So you are going mobile on EME! Very interesting,,
I do not use the BIG RAS.
As I understand it, the BIG RAS is a heavy duty model of the standard AZ/EL
RAS Combo rotor. I think that the the BIG RAS is very much bigger compare to my rotor.
Anyway,, I have used the "little" RAS for nearly 3 years on my 5m dish and
so far it has been working ok. Mechanics have no problem at all.The Spid rotor can have some strange behaviours electronicly.It is not of severy nature but it helps to understand how the rotor operates.I can explain more about it in later mail if you like to know.
I have always used for EME tracking the Orbitron software http://www.stoff.pl/ together with Spid Driver rotor controller software
For Spid Driver go here
http://www.sq7ro.net/krzysiek/index.php?option=com_content&task=blogsection&id=11&Itemid=38
Spid Driver is perfect piece of software with some very usefull functions
It is possible to calibrate/adjust AZ and EL positions "on the fly" and setup soft limits
Spid Driver can also be used as stand alone software.
I attach two pictures of my mechanical mount. Sorry the text are in Swedish, but you figure it out. The dish needs to be very perfectly balanced, because the Elevator is not so strong.
I use 24VDC external power supply for the rotor controller and this power supply MUST
have very good current capacity. It can happens during tracking that both motors (AZ and EL)
starts at the very same time. The start piek current from one motor can be neary 10Amp.
If the power supply in use is not strong enough the voltage will drop.
If the voltage drop the read out system will not function for a fraction of
time and the position will be lost with some degrees
At 24 volt the speed of the rotor is to fast for my taste. My rotor has no Slow start and stop function. I think the new version of AlfaSpid have this.
To solve this problem I did modify the Controller and use PWM (Pulse With Modulation)
on the DC voltage going to the motors.
With PWM I can reduce the speed without loosing to much tourqe of the motors.
Now the dish move smooth and nice but not so very very slowly.I dont like to wait 10 to 20 minutes to turn the antenna :-) I use a second RAS on my 10GHz tropo 85cm offset dish system
The Alfa Spid have 1 degree resolution and it is ok for this setup.
Both my Alfa Spid rotors for the EME and 10GHz systems are remote controlled
via LAN network .My schack is 100m away from antennas and all radio equipment are located at
the tower site.
If I can help you further just let me know,,
Good luck with your projects !
73's Håkan SM3LBN
