I was looking up the sweet Von Weise actuators (damned expensive), and ran across a very good price on an 18" Venture MA-71018-T.
I'd like to get some input on it, and later talk geometry.
First, $40 for a jack with 48 pulses per inch, seems quite a find.
I know there are two kinds of movers, recirculating ball and ajax nut.
(hope I got my terminology correct)
And for the modest price, I'm sure this is the lesser one.
What will that mean in the long run?
At $150 - 200 for a jack, plus the cost of a Vbox, that combo was well off my radar.
Now that Vboxes are down in the $40 range, as is this jack, I'm taking a new look at the whole idea.
So far, it's just thinking and talking.
I'm going to get well educated before spending money.
And, I'm really just planning ahead for a big heavy 1.0 - 1.2m Primestar or maybe a 1.8m commercial dish, which I don't yet have.
Until TurboSat started his thread on "Primestar to Polar Mount", I hadn't considered recycling a used C-band Polar mount.
Alternately, maybe something welded up out of bedframe material might get the job done.
I'd always wanted a correct H to H mount (and USALS control), but I'm seeing the light with a jack...
I guess I can work out the math to see how far from the dish pivot point I need to hook the jack, to cover a specific arc of the sky.
But, if anyone has a favorite web site that discusses those matters, I'd appreciate it.
How low on the horizon can I look and move, reliably?
Can I really use the entire 18" throw of the jack?
From my reading, 48 counts per inch of throw is as good as it gets - is that really good enough?
(until last week, I thought the 48 referred to 48 counts per turn)
How about wind loading, and actuator slop??
This other matter of flop-over when the dish has gone so far from one side of the arc (keeping the jack in compression?) to the other side (where the jack is in tension?) is something I can understand.
However, I could use some rule-of-thumb or other info on the significance and how to avoid the problem.
eg: does it affect east coasters, west coasters, northerners, southerners?
I'm at Los Angeles, for better or worse.
Your input is invited.
Comments and suggestions welcomed. :up
Insults and expletives ignored.
I'd like to get some input on it, and later talk geometry.
First, $40 for a jack with 48 pulses per inch, seems quite a find.
I know there are two kinds of movers, recirculating ball and ajax nut.
(hope I got my terminology correct)
And for the modest price, I'm sure this is the lesser one.
What will that mean in the long run?
At $150 - 200 for a jack, plus the cost of a Vbox, that combo was well off my radar.
Now that Vboxes are down in the $40 range, as is this jack, I'm taking a new look at the whole idea.
So far, it's just thinking and talking.
I'm going to get well educated before spending money.
And, I'm really just planning ahead for a big heavy 1.0 - 1.2m Primestar or maybe a 1.8m commercial dish, which I don't yet have.
Until TurboSat started his thread on "Primestar to Polar Mount", I hadn't considered recycling a used C-band Polar mount.
Alternately, maybe something welded up out of bedframe material might get the job done.
I'd always wanted a correct H to H mount (and USALS control), but I'm seeing the light with a jack...
I guess I can work out the math to see how far from the dish pivot point I need to hook the jack, to cover a specific arc of the sky.
But, if anyone has a favorite web site that discusses those matters, I'd appreciate it.
How low on the horizon can I look and move, reliably?
Can I really use the entire 18" throw of the jack?
From my reading, 48 counts per inch of throw is as good as it gets - is that really good enough?
(until last week, I thought the 48 referred to 48 counts per turn)
How about wind loading, and actuator slop??
This other matter of flop-over when the dish has gone so far from one side of the arc (keeping the jack in compression?) to the other side (where the jack is in tension?) is something I can understand.
However, I could use some rule-of-thumb or other info on the significance and how to avoid the problem.
eg: does it affect east coasters, west coasters, northerners, southerners?
I'm at Los Angeles, for better or worse.
Your input is invited.
Comments and suggestions welcomed. :up
Insults and expletives ignored.