Position keeps changing with new actuator

[N6BY]

A few months ago I purchased a new Venture actuator to replace the broken Super Jack on my 10' Unimesh. It's powered by a GBox, which never lost count with the previous motor.

When I say 'lost count' or 'position changing', I mean that if I move away from any given satellite and come back, it is in a different position. I use 121W (my south satellite) as the "0" position. After a day of use, 121W is around -100 ! Its so bad its unusable.

To move the dish, I simply use the GBox remote control and go to the number on the piece of paper where I write down the satellite positions. But now I can't do that anymore.

I am using the same shielded wire as I did with my Venture. I just swapped out the motor and now the positions are off. The more I move the dish and come back, the farther off it will be.

I got the actuator off of eBay and it is too late to return it.

Is there a fix to this problem, aside from buying another SuperJack?

 

[primestar31]

Try putting a .1 - 50 volt disc capacitor across the actuator motor terminals. The motor they installed may be sparking too much causing count issues due to impulse noise.

 

[stecle]

If you are using shielded cable you should have one bare wire which is called the drain. Ground this drain wire at the positioner (GBox) but do not connect the drain at the actuator.

I was told this at a satellite show in Vegas many years ago. I don't even know why it works. lol

 

[N6BY]

Try putting a .1 - 50 volt disc capacitor across the actuator motor terminals. The motor they installed may be sparking too much causing count issues due to impulse noise.

I assume the you mean 0.1 uF ? Will see if I can find one among my electronic parts.

If you are using shielded cable you should have one bare wire which is called the drain. Ground this drain wire at the positioner (GBox) but do not connect the drain at the actuator.

I was told this at a satellite show in Vegas many years ago. I don't even know why it works. lol

Yes, the cable does have a ground wire in addition to the two signal wires. Didn't have to ground it to the GBox with my Super Jack, but its worth a try.

... One other possibility: Is an 18" linear actuator under powered to drive a 10' Unimesh? My Super Jack was either 24 or 36 ".

What do you guys think? If it is too small of a motor I can get a 36" Super Jack from satellitesuperstore.com.

 

[primestar31]

I assume the you mean 0.1 uF ? Will see if I can find one among my electronic parts.

Correct. Solder it directly to the motor tabs on the actuator motor

One other possibility: Is an 18" linear actuator under powered to drive a 10' Unimesh?

Please tell me you didn't get the 18" Venture actuator? That isn't even made by them, (I believe it's a Superjack) and the older version at least isn't very good. That 18" Venture motor is the only one I recommend people NEVER buy.

 

[arlo]

Yes. A 0.1uF disc capacitor. Not electrolytic. Across the motor terminals can help reduce some motor hash that may cause false triggers. Extra counts would be an indication that motor noise is inducing to the sensor wires.
But it could go both ways I guess.
I would be very interested in seeing the reed switch/magnet in a clear photo. Keep your sensor wires twisted together up to both terminal strip ends.
Nothing says you may have a weak magnet or flaky reed switch. If the reed switch can mount diferently. Orientation does make a huge difference.
Superjacks are terrible quality. Is there even a genuine one out there? My brand new one needed extensive work to keep it living as long as it has. Things like loose brush screws that connected the motor wires. Soft brush carbon that decimated itself in less than a year of moderate feed hunting. Hardly any grease in the gear case. Motor magnet coming unglued. What else?
An optical pulse encoder in place of the original magnet/reed switch. Easily adapted to an ASC-1.
Got any good pics you could slap up here?

 

[N6BY]

My first motor was a Super Jack and it lasted about 16 years. I had to work on it twice during that time. It was a victim of being outdoors in the sun and rain.

I replaced it in October with a 18 " Venture actuator. (Hey, I had no idea it was so bad). The eBay seller I got it from hasn't responded to my email. Its too late for a return or feedback so he doesn't care. Caveat emptor.

I haven't found a 0.1 uF lying around here so I would have to order one.

I have to get some work done now, but I will try to take a photo later today after taking the cover off.

 

[primestar31]

My first motor was a Super Jack and it lasted about 16 years. I had to work on it twice during that time. It was a victim of being outdoors in the sun and rain.

I replaced it in October with a 18 " Venture actuator. (Hey, I had no idea it was so bad). The eBay seller I got it from hasn't responded to my email. Its too late for a return or feedback so he doesn't care. Caveat emptor.

I haven't found a 0.1 uF lying around here so I would have to order one.

I have to get some work done now, but I will try to take a photo later today after taking the cover off.

IF you keep that actuator, do yourself a favor and strap a flexible safety guy wire parallel with the full length of it. Something strong enough to HOLD your dish when that actuator breaks in half.

 

[arlo]

Don't be brand worthy. Superjack clones are rampant. I bought one from tek. It lasted about 2 years and I paid dearly for it. The gears ate themselves up. Poor weather sealing on the motor. Usual periodic teardowns. BTW I live in the North with nasty winters. If you got X years out of one then it must have been genuine. Not so anymore.
The 2nd one was practically given to me. A later model new in the box.
It's the one that had the quality issues.Dry gear case and motor bearings and loose brush wires blew me away.
After one of the magnets came unglued and was forced to taking it apart. Brushes worn and soft as a #1 pencil.
I have one of those 18" Ventures here torn all apart and yeah. The name went on before the quality went in.
Venture (the good ones designed for sat usage), Von Weise. Push a button and know it will do its job for years.
Not saying that a good PM here and there won't be a good thing....
I've been crucified for drilling a hole for a Zerk in my actuator tube and pumping it full on Lucas super low temp grease. I guess folks don't know what kind of rust and crud oozes out when you do.

 

[N6BY]

Below is a photo of the back of the actuator. I could twist the last few inches of the sensor wires, but I noticed that the mfr. didn't even bother to do the same with the black and purple wires going to the reed switch.

I am probably going to order a new actuator, but not until I get a working LNBF. Mine died tonight. It went from getting 17.5 dB on 127W (NASA Transponder) to "no signal". I have no idea how that happened. I checked the connectors and even tried the other output (it has 2). Still no signal.

Update: The LNBF is fine. The problem was my TBS6983 which may have died. WIll need to do some more testing with it.

 

[arlo]

Well holee-molee. There's your problem, Mister.
All wires running together in the same cable. No bwayno.
The sensor wires always at least have a shield wrapped around them if they are in the same cable.
No amount of twisting and separating will fix that. The sensor wires in the same sheath are usually smaller gauge also.
HTS Super Sensor. Houston Tracker Systems. Wow. You have an antique reed switch there buddy.
They went out of business when?
Try something. Pull your super jack magnet and the one in the what you have now.
Stick 'em to the fridge. That is if it's one made of good old steel. Which one is stronger?
If the other is stronger and the same size. Try that one.
The reed switch never being used, okay. But ceramic magnets loose strength over years.
No matter what. Motor power and sensor wires together and no shielding is a no-go. Even if your old supercrap unit worked good. I'm thinking not so, really.

 

[primestar31]

Where can I order a decent actuator? I don't wan't to order from TEK 2000.

Has anyone here had any experience with www.satellitesuperstore.com ? They are in the UK and shipping an actuator overseas could be very expensive.

You can order one direct from Venture. Get at least a 24" one, and then you'll know it's legit. Linear Actuators Manufacturer and Supplier in USA - Venture Mfg.Co.

It's likely to be at least $250. Or higher, since prices got all jacked up due to Covid hosing everything in the supply chain.

 

[N6BY]

Well holee-molee. There's your problem, Mister.
All wires running together in the same cable. No bwayno.
The sensor wires always at least have a shield wrapped around them if they are in the same cable.
No amount of twisting and separating will fix that. The sensor wires in the same sheath are usually smaller gauge also.
HTS Super Sensor. Houston Tracker Systems. Wow. You have an antique reed switch there buddy.
They went out of business when?
Try something. Pull your super jack magnet and the one in the what you have now.
Stick 'em to the fridge. That is if it's one made of good old steel. Which one is stronger?
If the other is stronger and the same size. Try that one.
The reed switch never being used, okay. But ceramic magnets loose strength over years.
No matter what. Motor power and sensor wires together and no shielding is a no-go. Even if your old supercrap unit worked good. I'm thinking not so, really.


View attachment 170109

The sensor wires are shielded (until they enter the motor box) and in a different cable than the power. I could wrap them in aluminum foil in the box

So what you are saying is that my 18" actuator is a new (very old stock) unit and the magnet is nearly dead?

Unfortunately I threw away my old Super Jack, so I can't swap out the reed sensor and rotary magnet. Are better ones available separately?

 

[arlo]

The sensor wires are shielded (until they enter the motor box) and in a different cable than the power. I could wrap them in aluminum foil in the box

Guess I got nuked out during some server work. Let's do this again.
I'd like to see that. Strip back a few inches of cable sheathing and show me.
Get those motor and sensor wires separated. Give them both as well as the sensor wires a few gentle twists up to the terminal strip. Keep the shielding on the cable sensor wires as close as you can up to the strip.
No foil needed. Just get that rats nest tidied up.


So what you are saying is that my 18" actuator is a new (very old stock) unit and the magnet is nearly dead?
I ain't saying nothing. Houston Tracker has been gone a long time. If Venture is using NOS parts. Who knows.
Ceramic magnets lose magnetism. Especially if they aren't kept on a soft iron "keeper".
You could pull the magnet and put it on a flat table. and run a sewing needle around the outside perimeter of it and see if the needle snaps to the 6 poles. Space it back several millimeters and check if each pole has the same strength.
I know I have an old one here that wreaked havoc on counts because just one pole was weaker than the rest.
That reed switch has to snap closed. Not just enough. It has to bang closed in a dead short. A magnet that is lazy and lets the switch bounce contacts will screw up counts.
Look at your pic and mine. Looks like your magnet has been rubbing. How close is it to the reed switch. A business card thick? Your switch has spacers. None of my old ones in "the box" do that I can remember. What's up with that?
I don't even know if Venture has replacement or retrofit parts for your unit.

Unfortunately I threw away my old Super Jack, so I can't swap out the reed sensor and rotary magnet. Are better ones available separately?
Shame Shame! Bet you wish you didn't.
Let's be Watney. Science the you-know-what out of this. If you buy another superjack. I'm sorry.

 

[N6BY]

... Orientation does make a huge difference....

So that's all I did - rotate it so the reed switch is level. Now it works fine. No changes to the wiring were necessary.

 

[espaun206]

You can order one direct from Venture. Get at least a 24" one, and then you'll know it's legit. Linear Actuators Manufacturer and Supplier in USA - Venture Mfg.Co.

It's likely to be at least $250. Or higher, since prices got all jacked up due to Covid hosing everything in the supply chain.

I quoted a 36-inch Maxi at Venture and they are super expensive, at Rick they are cheaper but I don't know if they are original Venture

 

[espaun206]

Question: Are those who sell at Rick legitimate venture? And if these venture Max are identical to those in the imagen color

 

[telstar_1]

That looks similar to a type I tried near my end of C-band. Actuators were the bane of my (& customers') existence. None would last over a bare few years, even Von Weise. Anyway, this one actually held up well operationally, but like the problem presented here, counts went off, and I'd never really had that issue before. I got lucky and figured it out on my own dish when the wind was blowing hard. On high gusts, I could see the tube retracting slightly. The force on the jack was actually enough to rotate the motor...

 

[arlo]

I wouldn't guess that Rick's doesn't sell kock-offs. More likely he gets a break on quantity.
The owner of Von Weise in Mexico was very nice to talk to. In my book they make the Cadillac of actuators.
But he does not keep a stock of satellite actuators, rather builds to order. And I was offered a quantity break.
Great idea for a group buy.
There are several factors involved in mechanical things out in the weather. My Superjack has lived its cat lives because I value my hard-earned money. And a bit of a geeky mechanical/electrical/electronics dude.
The accordion boot is a great thing to have. Of all of the Saginaw, Venture, rebadged ones by the name of Houston Tracker. All of the screw tubes are gooked full of rust and caked up grease. Any grease in the geartrains looks like old wax.
I stand by my Zerk screwed in the tube, shallow by a few threads. Extend it fully once a year or so and give it a few pumps of Lucas super low temp grease and I'm good to go. Stick the motor/gearbox on the bench every so often and clean and grease it. New brushes if it needs it. I get mine from Ace. Closest size a bit bigger and sand them to size with a dial caliper to keep track.
Those Venture 18 inchers. I have 2 here. Dispose-a-jack. Seriously.
The dish retracting in the wind. Wow! I've extended the tube mount on my 'glass 12 footer with angle iron and bolts.
I use almost all of it's 36 inches from 127W all the way out to 30W. The dish originally uses a 24 inch tube.
It takes its sweet time traversing the arc. But when it stops. It stops. With a pull-back spring and cable to take care of over the center "flop". Longer fulcrum, less weight for the actuator, gears, and motor. And probably the dish mover current draw.
I know before when it got 0 or below. She would grunt heavy and give motor errors. Now? History.
I have dagger wounds and stone welts from people with disposable income telling me there's no need for grease or periodic PM. I guess our common sense clashes.
Here's my offer to the geeks with boxes of parts. A dynamic brake that will stop that motor cold in its tracks. It may not keep wind from moving it (you need to solve that). But it will Definitely cure a heavy load retraction of the tube when the motor stops. And absolutely help with accumulated mover count errors when you "bump" the dish to locate and store satellite position.
The relay is a DPDT mini relay with 10A contacts and 24 VDC coil. 10A is overkill but what I had in the box.
R1 can be a 1-5 ohm 1/2-1 watt resistor. Or a .33 ohm emitter resistor from an old solid state amp.
Mine is just a short. I don't need no steenkin' reesistor. Seriously. No ill effects from not having R1.
R2 is a current limiting resistor. In case your dish mover delivers considerably more than the 24 VDC coil rating.
My brake has its home inside of the gearbox cover. Fits real nice.

 

[telstar_1]

Maybe needless to mention but of course the real "cadillacs" of C-band were the H to H (armless, self-contained gear drive) mounts. Most were pretty good, though of course some better than others. But pricey.