Where to get converter to control servo with 14V/18V switching receiver?

[bosskong]

Hi everyone, I have a Corotor II feedhorn with a servo motor and C and Ku lnbs. I've been using a Fortec Ultra and recently I got a DVB PCI card. The receiver has been connected to a little box that I got on ebay a couple of years ago that takes the 14V or 18V from the receiver and turns the servo motor the right way. It worked great, up until a few weeks ago...

I didn't do any proper weatherproofing when I installed the feedhorn and this electronic circuit was sitting in a baggie full of rusty water. I took it apart and tried to repair it, but some parts were burned or completely rusted through and without schematics, I never could get it working correctly.

Is there anyone who could help me fix the circuit that I have or does anyone know where I can find another one? I can post pictures if anyone needs them.

 

[charper1]

Like these?

http://www.daveswebshop.com/servomotor.shtml

http://www.skyvision.com/store/mi3503019.html

 

[bosskong]

Well, no... my servo motor works fine. Here's a picture of the box that I had that was working great. It connects to the receiver and to the servo motor and it turn the servo based on whether it receives a 14V or an 18V signal.

 

[Likvid]

Ok, but you can't fine adjust the skew right with that device?

 

[WyrTwister]

Well, no... my servo motor works fine. Here's a picture of the box that I had that was working great. It connects to the receiver and to the servo motor and it turn the servo based on whether it receives a 14V or an 18V signal.

Pretty good idea . If you find a source , please PM me .

Wyr

 

[dfergie]

to SatelliteGuys and the C-Band forum bosskong...

 

[bosskong]

Thanks for the welcome... No, you can't adjust the skew independently for each satellite like you can with an analog receiver, but I don't care about that. When it worked, it worked better than the cheap lnbf I'm using now. Come on, somebody has to have seen one of these for sale or have an idea about how to build one.

If I send pictures and answer some questions, is there anyone who thinks they'd be able to help me figure out what's wrong with mine? It's not that complicated of a circuit, maybe 20 parts in all (a 555 timer, 7805, some resistors, diodes, and caps).

 

[dfergie]

Put it up... there are a lot of resourceful folks here... Maybe the FTA folks can chime in with info...and Your Welcome...

 

[bosskong]

OK, here goes. Here's a couple of pictures. I'm right in the middle of studying for an organic chem test, so I apologize for not drawing out a crude schematic, but I don't have time right now. I'll try to do that in the next couple of days.

Anyway, like I said before, the circuit was sitting in a bag of rusty water, so a lot of the parts rusted away. I replaced 2 of the diodes, 4 or 5 of the capacitors, and the 2 transistors. One part that I wasn't sure about was a resistor. One of the bands had burned off, so I couldn't read the specs. It was a large 3-5 watt resistor, somewhere between 10 and 19 ohms. So, I replaced it with a 15 ohm resistor. Any thoughts about what the correct value might be?

The actual pcb was somewhat damaged, so every time I solder to it, I'm afraid that I'm damaging the tracks. It's really hard to tell what is supposed to connect to what.

Anyway, after I replaced some of the parts, put the circuit back together, and connected it to a receiver, the +5 and GND terminals have the correct voltage coming out. The circuit will turn the servo motor if I use a screwdriver on the skew adjustment screw. But when I switch between H and V channels, nothing happens.

I'll post more details in the next few days when I have more time, but in the meantime, any help would be much appreciated!

 

[dfergie]

That switch looks familiar to me somehow...

 

[charper1]

call Daves' Webshop for some help

http://www.daveswebshop.com/

Is it a polorizer converter?

 

[bosskong]

I'll try calling tomorrow, but I don't think he's gonna have one. I called it a polarizer converter, but it's not really a standard part. Most people have never seen or even heard of one of these circuits.

But, I'll call him and let you know what he says.

 

[bosskong]

As I'm drawing chemical formulas, these thoughts keep popping in my head, so I'll spit them out real quick. I'm obviously not an electronic circuits expert, but I came to a few conclusions. Please let me know if I'm wrong about anything.

I get a good +5V output, so I assumed that the 7805 was working and I didn't replace it. Since the servo can be turned with the adjustment screw, I assumed the 555 chip was working by sending out a pulse, so I didn't replace it either. I replaced the only 2 transistors, but now I don't know what to do...