SG2100 Woes

Phalaenopsis

SatelliteGuys Pro
Original poster
Nov 24, 2017
457
275
NA
I’m finally back into the FTA game! After not using my motorized dish setup for over a year, I finally decided to fire up my old SG2100. Unfortunately, my SG2100 will not work. Whenever the motor is connected to a receiver the motor will not receive any DiSEqC or USALS commands. I tried swapping out my Amiko Mini HD RE with a old Pansat receiver and the motor will still not receive any commands. The funny part is that the motor works perfectly when I press the manual button on the motor. I tried resetting the motor and both receivers but the motor still doesn’t communicate with the receivers. The motor has a steady green light, it moves when I manually move it, and the satellite signal still passes through. I took the motor apart, and started testing the components on the circuit. I did a quick inspection of the diodes and capacitors with a multimeter and they seem to be normal. What could my problem be? What components could have failed on the circuit? I’d really like to get this motor fixed and back in service

Attached are some circuit diagrams I found and some pictures of my circuit.
Adjustments.JPG
Adjustments.JPG
677551C1-1577-464D-8CD5-612D98471B5D.jpg
IMG_1686.JPG
 
An 18 volt laptop power supply was added to this board. This modification was done before I received the motor.

Sent from my SM-G973U1 using the SatelliteGuys app!
 
I can't say that removing that would help. You may have a bad F fitting. The center conductor not making good contact inside the fitting.
 
Is the LNB voltage enabled on the STB? What is the STB voltage on a vertical and on a horizontal polarity transponder?

Yes, the LNB voltage is enabled on the STB. I’ll test the STB voltage on the vertical and horizontal polarity transponders tomorrow, but I don’t think the STB is the problem. I tried this motor on a total of three STBs, a Manhattan DJ 1997, a Amiko Mini HD RE, and a Pansat 3000. I soldered the F-Connector in place, and I temporary reversed the power supply mod by temporary bridging the wires together. The motor moves perfectly fine when I press the manual button on the circuit without the external power supply. The receiver is providing sufficient voltage to the motor to move it. The motor is not receiving any DiSEqC or USALS commands from any of the receivers. When I connected the C5 capacitor to the GND pin on the U3 controller with a solder stick could hear the relays clicking. Tomorrow I’ll take my multimeter out and measure the receivers voltage, and I’ll begin testing capacitors. I think my problem could potentially involve one of the following components: C4, C5, U3, C7, C8, C1. I’m really stumped.,
Adjustments.JPG
 
More pictures:
IMG_1714.JPG
Adjustments.JPG



Also, here is the link to the laptop power supply mod. This mod did not cause the problem.

 
  • Like
Reactions: k.r.
Ok, just wanted to check the obvious first. Many users do not realize that the STB power must be enabled for the 22KHz/DiSEqC signals to be issued.

Does the motor's green operation LED flicker yellow when a DiSEqC command is issued or always remain solid green?

If you have a scope, check the PCB path between the f-fitting and the decoder IC for DiSEqC signal. If no scope, many cheapo satellite meters have a 22KHz ON/OFF LED indicator that can be used as a DiSEqC sniffer. Is the DiSEqC sognal being passed through to the motor's LNB port? If DiSEqC is present at the motor's input receiver port, but not the loop-through LNB port, the defect may be in the tap. If loop-through is present, then the defect is in the decoding circuit.

A component failure could be blocking the DiSEqC signal. Worst case is the motor may have been exposed to an electrical event and damaged.
 
I checked the voltage output of the Amiko Mini HD RE. The Amiko outputs 18.49 volts on horizontal transponders and 13.39 volts on vertical transponders. The motor LED stays green when DiSEqC or USALS commands are issued. The DiSEqC signal is present through the loop out LNB port. The 22K light on the satellite meter is flashing whenever a DiSEqC pulse is being sent through the receiver. What could my defect be in the decoding circuit?
 
Both the 22K (green LED) and the H/V (red LED) are on. The green 22K LED sometimes flashes. Also, out of nowhere, the motor randomly started moving when I issued a DiSEqC command to it's Western limit. That was the only sign on life I got out of this motor when a command was issued. The motor never moved again today
20200222_182852.jpeg
 
***

Users Who Are Viewing This Thread (Total: 1, Members: 0, Guests: 1)

Who Read This Thread (Total Members: 8)