Help Required Mutant/AX HD51 not driving motor

Captain Jack

Captain Jack

Retired human
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Having recently set up a DiSEqC "Dark Motor", I am having trouble driving it with my Mutant Enigma2 box.

The setup is simple; tuner B is connected to the motor, which is configured for USALS. The issue is that the receiver simply does not move the thing. When I reboot the box, it *may* move it once or twice to the designated satellite but mostly it does nothing. This happens when I either select a channel or issue a command from the positioner setup menu. Nudging the dish with either "movement" or "fine tune" control has no effect. It's almost as if the motor is not receiving the DiSEqC commands. Given that it works *sometimes*, I don't suspect it to be a setup issue but a compatibility problem between HD51 and the Dark Motor.

I've read that the Dark Motor does have this issue with some E2 boxes but unclear as to why... Could it be the long-ish cable run and it's unable to send enough juice to it? I could try adding an inline power supply...

I have no issues driving the motor with my GTMedia meter or the F15 receiver, so it's definitely isolated to the HD51 receiver or its compatibility with the motor.
 
I've had a similar situation with a STAB motor, and long and not high-quality cable, including several barrel connectors.

With one receiver it gave problems in normal use (but strangely, when giving motor commands directly from the motor menu, all went well). With a short cable near the dish, there were no problems.
However with another receiver and the long cable, there were no problems at all.

I just went on using the receiver that gave no problems. So I don't know how I could have improved the situation with the other receiver.
I don't think it is a 'juice' problem though, as 13V or 18V did not make a difference, if I remember well (I think I tested that, but it was quite a while back...).
It might be a problem how "loud" the diseqc command is sent?
If I were you, I'd check with a higher quality cable, I think.

Greetz,
A33
 
Thanks for the response. About 20 years ago, I drove a 1.2m Gibby on an old Moteck 2100 motor at the end of a 50m cable - the Dreambox at the time absolutely did not like it. Very intermittent until I added an inline power supply. Then it worked without issues. I did not have another receiver to test it with then.

I am not convinced that the cable is the issue here. It's brand new CT100 type and a single run with no joins anywhere. There is no signal loss at all. That said, I did not check it close to the receiver... Rookie error.

The voltage is not the issue, it's the current that matters. If the PSU is "lazy", it may not provide enough amps but that's speculation.

The DiSEqC commands being 'lost' seems like what's happening here. So maybe the receiver isn't shouting loud enough - perhaps the commands are getting lost in the noise somewhere along the way?

I'll try a different image with a new install just to rule out configuration issue. Will also try it from tuner A and see if there's any difference.
 
Captain Jack said:
The voltage is not the issue, it's the current that matters. If the PSU is "lazy", it may not provide enough amps but that's speculation.
Click to expand...

So you think the receiver might have a current limiter? Could be, of course. Otherwise, 18V would result in higher current.
Or do you even think, the over-current protection has set in?

Can you measure voltage and current under operation, to maybe see something happening, and diagnose this?

Did you try if the motor moves, with LNB disconnected (so not using power anymore)?

Does your motor have buttons, for 'manual' MoveLeft/MoveRight operation? When they do function normally, it is not a juice matter, I would say.


These are just some thoughts, maybe they help? I've never done such testing myself, though.

Greetz,
A33
 
All good suggestions, thank you. The dish is a bit of a pain to get to, so I'll try some things on the ground first.

I am not sure if it's over current protection or just simply not enough juice. I would have thought that simply nudging the dish using "fine adjustment" would have move the dish even a little bit. But it's almost like it's not getting the commands at all.

The motor does have left/right buttons so it's a thing to try.
 
To be fair, I've had the same problem for years, however a couple of days ago the external power supply died suddenly and I temporarily replaced it with the one from OsMio 4K. And so far the motor has worked flawlessly. In my estimation, there seems to be some peculiarities with the voltage that this chipset requires for optimal function. Too little is insufficient, and too much causes issues. So there's something to consider...
 
Interesting - so that aligns with the power supply theory.

I will temporarily try my bench power supply and see what the current draw is...see if that makes a difference!

Out of interest, is there a difference is power supply spec? Also, is this on the HD51 receiver too?
 
Whats the DC current specification for the antenna output on your receiver?? Most DiSEqC controlled motors that I remember need at least 350 mA of DC current at +12 volts or better, coax with a copper plated core can also cause problems, if it got water inside the core could have rusted.

On satellite systems with a motor I use coax with a pure copper center conductor, no degradation of voltage (too much voltage drop) or lack of current (too much DC resistance on the coax) to drive the motor, also a poor connection on the coax shield can cause problems.
 
Does the Mutant receiver have a DiSEqC repeat function in the settings ?
 
a33 said:
Can you measure voltage and current under operation, to maybe see something happening, and diagnose this?

Did you try if the motor moves, with LNB disconnected (so not using power anymore)?

Does your motor have buttons, for 'manual' MoveLeft/MoveRight operation? When they do function normally, it is not a juice matter, I would say.
Click to expand...

By the way.
I'd do these tests both for a horizontal channel, and a vertical channel.
If with 13V it works, but fails with 18V, it might be an over-current protection issue.
If with 18V it works, but fails with 13V, it might be not enough power supplied/arriving at the motor.
 
Captain Jack said:
It does but that doesn't help.

@Terryl I am discounting the cable as the cause (other than the long run) as it's brand new with compression connectors
Click to expand...
If you can change the lower compression plug it may be a quick fix. I have seen too many fitted that fail to make a good shield contact.
 
Captain Jack said:
It does but that doesn't help.

@Terryl I am discounting the cable as the cause (other than the long run) as it's brand new with compression connectors
Click to expand...
OK but what type of center conductor?? You can use a small magnet to find out, if the magnet sticks it's copper plated steel.

Some coax with the copper plated center (but not all) have a higher DC resistance then the pure copper stuff, if you make up a shorting plug and connect it to the far end (without the receiver hooked up) then you can measure the total DC resistance of the run of coax, the center conductor is one way out, the shield is the return, the combined DC resistance is what determines how much DC voltage is lost in the coax.

The coax may be new but who knows if it may have a problem somewhere in the run, something like a stretched shield or it got pinched somehow maybe before installation, who knows.
 
OK, I faffed with it yesterday to try to figure stuff out but not really any closer.

The first thing I tried is a bench power supply as it gives you the power consumption of the receiver. When idly watching a channel, the consumption is around 1A. Whenever it drives a dish, the consumption increases by around 250mA. However, it was still very unpredictable as to whether the dish would move. When I instructed to move the dish but it didn't move, the current consumption jumped by ~200mA for a split second before settling. So it looks like the command does reach the motor, the motor tries to move but for some reason the receiver cuts out before anything happens.

Oddly, sometimes I can move it in one direction but not another (usually east but not west). I tried different images and both tuners but in the end it was still hit and miss.

My suspicion is that it the motor wants more current than the receiver can provide, though ~250mA is hardly breaking the bank. Perhaps the initial start-up/surge current is much higher than that and the receiver gives up?

I am going to try swapping the cables around, as I have two running from the dish to receiver - just on the off-chance some kink or pinch is causing this. In the meantime, I've ordered an SF8008 receiver to see if that has similar issues...
 
There used to be in the distant past (I think around 2016) a serious issue with the drivers of HD51 not providing the correct commands for the motor to function properly, which was fixed but it looks like the last gfutures driver pack that was released somewhere in 2018 (yes no driver update since then) reintroduced some issues.
Now, it's a pity that the whole HD51/AX51 chipset is based on these old gfuture drivers, especially for the Silabs demod part. On the contrary, SF8008 has much newer and different drivers, which solved many of the known persisting issues.
 
The only other member that found anomalies with dark motor stock here was a few years back, though he was happy running DiSEqC 1.2 without the USALS function (and I had no request to swop out).
Will look for the thread after dinner in case there is a link.
 
MCelliotG said:
Now, it's a pity that the whole HD51/AX51 chipset is based on these old gfuture drivers, especially for the Silabs demod part. On the contrary, SF8008 has much newer and different drivers, which solved many of the known persisting issues.
Click to expand...
Technically, it should be possible to get the latest drivers by building them from source. If the source is available.

The SF8008 I bought, hopefully the V2 version, has Availink tuner, which I hear has the ability to display SNR before lock with some modifications to the drivers and E2. This was for one of Edision receivers, using the same tuner.

The other reason I wanted this tuner is to get finer SNR dB granularity. The 0.25dB stepping for Silabs always annoyed me - despite being decent tuners overall.
 
Years ago I had a modified sat receiver I used to monitor the DC current going out to the motor and LNB without disrupting the signals from the LNB, this receiver is no longer around to tell exactly what the modification was.

If my old memory serves me I think it was at the output of the variable power circuit just before it gets injected into the RF stream out to the LNB/Motor, a circuit trace was cut and a .1 ohm 1% 1 watt (I think) resistor and some RF chokes on the output side was added, then a millivolt meter was used to monitor the DC current draw across this circuit. (using ohms law)

I found that most of the FTA satellite receivers at that time could handle at least 500 mA or a bit more of DC current, while some of the newer ones with the separate DC wall wart power supply's lacked the required current to move the motor and supply enough current for the LNB and receiver to operate correctly, the receiver would re-boot or just shut off, OEM provider receivers could supply quite a bit more.
 
The previous (before the last) revision of gfutures had somehow managed to provide increments of 0.12dB, I don't know how this could be possible knowing Silab's hardware limitations. I could reinstall an old image to test, but I cannot simply remember the dates.
Now, SF8008 V2 does have Availink, but unless I recall incorrectly, the TNAP team that brought the mod was unable to activate the non-lock signal feature on SF8008, just on Edision.
Captain Jack said:
Technically, it should be possible to get the latest drivers by building them from source. If the source is available.

The SF8008 I bought, hopefully the V2 version, has Availink tuner, which I hear has the ability to display SNR before lock with some modifications to the drivers and E2. This was for one of Edision receivers, using the same tuner.

The other reason I wanted this tuner is to get finer SNR dB granularity. The 0.25dB stepping for Silabs always annoyed me - despite being decent tuners overall.
Click to expand...
 
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