HitecAstro DC Focus Controller

[emadmoussa]

Hola,

In the effort of automating my AP, I was left only with the focus to remotely control. I already used a 5-meter J10/9 cable which worked well, but was quite awkward and a bit ''dangly'' . So I decided to go for the Hitec Astro DC Focus Controller.

I ordered it from Modern astronomy along with a second SW motor focuser to fit onto my 80ED. If you buy in bundle it costs slightly less than buying them separately. Anyway, it arrived promptly, but only today I had the chance to test things out. So here's my brief review:

Same as most of those astronomy adapters and interfaces, the packaging was no more than a bubble wrap in a little box. The controller casing is made of light weight plastic. Would've been nicer if the plastic was a bit thicker just to provide further insulation for the electronic board inside from weather related effects. I haven't tried it outside yet, so I don't know how effective the protective casing will be. All in all, it seems solid enough, hence I'm not very concerned.

In order for the controller to work it requires 12v power plug. It comes with a ''built-in'' 12v cigarette AC plug. For me, this is not a plus for two reasons: It would've been more flexible if the adapter wasn't built in so you can remove it and pack it away instead of being attached to the controller all the time. I was specifically dissatisfied about the fact that for the price they could've added a 12v DC adapter as well. I don't use a power tank or have a car, so a cigarette adapter was useless . I had to buy a AC/DC power adapter to get it hooked to the house mains.

Bear in mind that the package doesn't include a USB cable (standard printer USB cable). Luckily I have a bunch of them, so didn't bother me much. You can always get a 2-meter one for 99p off Ebay. But again, why wouldn't they add a USB cable?!! It's not like it'll break their back financially...will it?

Performance (indoors testing):

All the above aside, I was quite happy with the performance.

Out of the box (or the bubble wrap) I connected it to the computer using the USB cable and the other end to the motor (not attached to the telescope). Downloaded the software from www.hitechastro.co.uk and there you go....working like magic.

The interface is a classic ASCOM looking interface and works within that environment. It gives way more freedom in controlling your focuser. The main pain with motorized focuser has always been their slow spin speed even at max velocity. The software allows you to go beyond the conventional speed...visually pick your speed, slew and focus ''continuously'' or ''in steps'' and more. For astro-photography this is certainly a great advantage.

Left to say that the controller, which you'll mostly leave on/by the mount, has two little cheap looking in/out buttons which enables you to control the focuser manually should you move away from you laptop. You don't really need your motor handset.

Oh, also...for the record, when you focus in or out it gives you a little peep...which I thought was nice

Would I recommend it?

It depends, if you want a high precision remote controlling of your focuser...then go for it. It's a very nice piece of kit.

[dmahon]

I agree entirely about the captive power cable - and not just on this product from this manufacturer. What a stupid "design feature".

Other than that, it's a nondescript plastic box that does exactly what it's supposed to. I can't get steps less than 10 to do a great deal, and it doesn't work with focusmax etc., but what do you expect from DC motors? It means I can polar align my mount and then retreat inside, setting up focus and everything else from the warmth of my office. I'd prefer stepper motors, but that's an additional £175.

[sloz1664]

I think you will find it does work with FocusMax. I use it in conjuction wilh MaximDl. It's a cracking bit of kit for the money.

I use it for the same reasons - focussing indoors. Another plus point the SW dc motor stops my std ED80 focuser from slipping

hence saving me money in a focuser upgrade.

[emadmoussa]

I think you will find it does work with FocusMax. I use it in conjuction wilh MaximDl. It's a cracking bit of kit for the money.

I use it for the same reasons - focussing indoors. Another plus point the SW dc motor stops my std ED80 focuser from slipping

hence saving me money in a focuser upgrade.

It did actually tighten up the focuser...double edged sword indeed.

[dmahon]

Despite them having an ASCOM driver that pretends to be a stepper motor, I never got it working successfully with focus max and Maxim on either of my scopes. Still, it's not too hard to do manual FWHM focussing.

[alcol620]

Hi folks

Took delivery of this and the SW motor to fit on my ED80. Used the Youtube video to fit the motor, there is a need to modify the bracket to fit. My experience as follows: By following the video the conversion was relatively straight forward. The problems only started on testing the work. It was apparent right away that the friction required on the draw tube needed adjusting. But you could no longer get to the adjusting screws, the holes in the bracket did not line up. Why should they they didn't line up for tightening the grub screw on the shaft, hence the video. In addition, because the heads of the 2 friction adjusting screws stood proud off the focuser spindle holder assembly, the bracket supplied for fitting did not fit flat and depending how it was tightened, the alignment of the motor and shaft changed significantly causing the motor to become loaded and on occasions stopped. The answer was to widen the holes in the bracket so that access could be gained to the 2 friction adjusting screws. These holes were also countersunk to allow the bracket to sit flatter on the focuser assembly. A further hole was drilled to allow the draw tube fixing screw to continue to be used when required. It took quite a while to adjust the friction screws so that the motor would drive the draw tube in and out at high and low speed. There was a fine line in adjustment, from the motor not able to drive the draw tube because of friction tightness and not being able to drive it because the friction drive was too loose. Obviously, when using the focuser by hand, everything can be much tighter, but with a small motor the margins are much tighter. Tested the motor on the scope yesterday the motor controlled the focuser for a while, then the draw tube suddenly slipped down to the end. I had the filter wheel and the atik 383 on the end so a bit weighty Anyone have any ideas how this can all be tightened up and still get enough power from this small motor to drive the draw tube in and out? I haven't tried the DC focus controller yet - still trying to get the motor to hold the tube without slipping.

[Starlight 1]

Hi folks

Took delivery of this and the SW motor to fit on my ED80. Used the Youtube video to fit the motor, there is a need to modify the bracket to fit. My experience as follows: By following the video the conversion was relatively straight forward. The problems only started on testing the work. It was apparent right away that the friction required on the draw tube needed adjusting. But you could no longer get to the adjusting screws, the holes in the bracket did not line up. Why should they they didn't line up for tightening the grub screw on the shaft, hence the video. In addition, because the heads of the 2 friction adjusting screws stood proud off the focuser spindle holder assembly, the bracket supplied for fitting did not fit flat and depending how it was tightened, the alignment of the motor and shaft changed significantly causing the motor to become loaded and on occasions stopped. The answer was to widen the holes in the bracket so that access could be gained to the 2 friction adjusting screws. These holes were also countersunk to allow the bracket to sit flatter on the focuser assembly. A further hole was drilled to allow the draw tube fixing screw to continue to be used when required. It took quite a while to adjust the friction screws so that the motor would drive the draw tube in and out at high and low speed. There was a fine line in adjustment, from the motor not able to drive the draw tube because of friction tightness and not being able to drive it because the friction drive was too loose. Obviously, when using the focuser by hand, everything can be much tighter, but with a small motor the margins are much tighter. Tested the motor on the scope yesterday the motor controlled the focuser for a while, then the draw tube suddenly slipped down to the end. I had the filter wheel and the atik 383 on the end so a bit weighty Anyone have any ideas how this can all be tightened up and still get enough power from this small motor to drive the draw tube in and out? I haven't tried the DC focus controller yet - still trying to get the motor to hold the tube without slipping.

As in post 1 you can see the software , its got two sliders at the top this is for the motor power once you got it right save to controller.

[alcol620]

It seems as if the motor is not powerful enough to drive the focuser tube if the motor shaft is adjusted so it is too tight on the focuser tube.. The margin of adjustment is small, varying between not driving the shaft when the focuser tube drive shaft is tightened down to much, to the motor shaft not driving the focuser tube when the pressure on the drive shaft is relaxed to much. Finding it very difficult to find that good spot in the middle.  I have checked the flat on the focuser to make sure it is flat and doesn't need filing down. It looks Ok. Checked the 9v battery driving the motor, this is fine at about 9.6v.

Can't see any other adjustments to get consistent operation.

[Starlight 1]

Well my one drive a tak 106 ed with a 3"tube, filler wheel and starlight 694 ccd and it hold very well. its not the motor.

[alcol620]

It looks as if I need to remove it all and start the assembly again, could be something to do with alignment!

[Thalestris24]

Hi folks

Took delivery of this and the SW motor to fit on my ED80. Used the Youtube video to fit the motor, there is a need to modify the bracket to fit. My experience as follows: By following the video the conversion was relatively straight forward. The problems only started on testing the work. It was apparent right away that the friction required on the draw tube needed adjusting. But you could no longer get to the adjusting screws, the holes in the bracket did not line up. Why should they they didn't line up for tightening the grub screw on the shaft, hence the video. In addition, because the heads of the 2 friction adjusting screws stood proud off the focuser spindle holder assembly, the bracket supplied for fitting did not fit flat and depending how it was tightened, the alignment of the motor and shaft changed significantly causing the motor to become loaded and on occasions stopped. The answer was to widen the holes in the bracket so that access could be gained to the 2 friction adjusting screws. These holes were also countersunk to allow the bracket to sit flatter on the focuser assembly. A further hole was drilled to allow the draw tube fixing screw to continue to be used when required. It took quite a while to adjust the friction screws so that the motor would drive the draw tube in and out at high and low speed. There was a fine line in adjustment, from the motor not able to drive the draw tube because of friction tightness and not being able to drive it because the friction drive was too loose. Obviously, when using the focuser by hand, everything can be much tighter, but with a small motor the margins are much tighter. Tested the motor on the scope yesterday the motor controlled the focuser for a while, then the draw tube suddenly slipped down to the end. I had the filter wheel and the atik 383 on the end so a bit weighty Anyone have any ideas how this can all be tightened up and still get enough power from this small motor to drive the draw tube in and out? I haven't tried the DC focus controller yet - still trying to get the motor to hold the tube without slipping.

Hi

You have to be careful to ensure all the allen grub screws in the coupling are sufficiently tightened. It should be hard to manually adjust the focus with the SW 'autofocuser' motor attached.

Louise

[alcol620]

Thanks Louise

Yes it's all tightened up. Had another go at adjustments yesterday seems to be less slippy now. However, if I tighten down the pressure pad on the motor spindle too much the motor won't turn the spindle. Now attached the Hitecastro dc focus control and this drives the motor with a higher voltage up to 12v whereas the SW auto focuser only had a 9v battery driving the motor. This means I can tighten the motor spindle down harder without the motor failing to drive it round.

Thanks again for your input

Alec

[Thalestris24]

Thanks Louise

Yes it's all tightened up. Had another go at adjustments yesterday seems to be less slippy now. However, if I tighten down the pressure pad on the motor spindle too much the motor won't turn the spindle. Now attached the Hitecastro dc focus control and this drives the motor with a higher voltage up to 12v whereas the SW auto focuser only had a 9v battery driving the motor. This means I can tighten the motor spindle down harder without the motor failing to drive it round.

Thanks again for your input

Alec

Hiya

9V is more than enough! Mostly the autofocuser is used to make tiny, almost imperceptible adjustments. This is a useful video

Louise

[alcol620]

Hi Louise

Yes, I watched that video, most helpful. What it didn't show was the need to drill out the other holes on the bracket so that if there was a need to adjust the  neoprene pad arrangement on the motor shaft allen keys could be used to reach the grub screws. (The video shows these holes are not aligned after the bracket is fitted and the grub screws can't be accessed after the motor bracket is fitted

Regards

Alec 

[Thalestris24]

Hi Louise

Yes, I watched that video, most helpful. What it didn't show was the need to drill out the other holes on the bracket so that if there was a need to adjust the  neoprene pad arrangement on the motor shaft allen keys could be used to reach the grub screws. (The video shows these holes are not aligned after the bracket is fitted and the grub screws can't be accessed after the motor bracket is fitted

Regards

Alec 

Um, if you follow the video there shouldn't really be any need to adjust anything after fitting. Everything should be free running using the motor but quite hard to move manually. Having said that, I've only fitted them to my pds scope Crayfords and to an ST80 R+P. Also, it's the motor that holds focus, not the pressure pads. If the motor isn't holding everything then maybe something isn't fitted right? Maybe one of the grub screws on one of the 'inner' couplings? It's easy to miss one as I can testify!

Hope you get it all working smoothly

Louise

[alcol620]

Thanks Louise

I'm reluctant to undo it again, but I will have to bite the bullet and do it. Just for information, how tight do you wind down the central grub screw that pushes the neoprene washer down onto the focuser shaft?

Regards

Alec

[Thalestris24]

Thanks Louise

I'm reluctant to undo it again, but I will have to bite the bullet and do it. Just for information, how tight do you wind down the central grub screw that pushes the neoprene washer down onto the focuser shaft?

Regards

Alec

Hi Alec

It's a long time since I fitted mine but I don't recall having to use a great deal of effort to tighten anything. I do remember that the 4 little O-rings are easy to drop and lose on the floor... But they are a critical part...

Louise

[alcol620]

Thanks Louise

[Thalestris24]

Hi Alec

Well it looks like being a good weekend for scope fiddling... If you do undo the focuser you'll be able to see how much effort it takes to manually rotate the motor - it should be pretty stiff as they are geared dc motors 

Louise

[alcol620]

Louise

Does seem strange that I can tighten the neoprene friction pad to the point that it stops the shaft of the focuser rotating and I can still hear the motor (not sure if it is rotating). I will investigate tomorrow and provide an update.

Alec

[alcol620]

Hi Louise

Had the assembly to pieces again today and made sure all the grub screws were well tightened. Adjusted the tension on the neoprene washer and all seems to work better than it did. However, I did notice the the motor looks as if it has some sort of flexiible coupling held by a grub screw inside the metal sleeve on the shaft of the motor. I think this is a candidate for slippage if the motor tries to drive against a too tight focus assembly.

As you said yesterday, a weekend for scope fiddling.

Regards

Alec

[Starlight 1]

Sounds like you are useing the siver one ? that one only fit by a o ring on one end with the grub screw to motor .only the black one have 2 grub screws .

[alcol620]

Hi Starlight

Looks like the attached. Is that what you mean by the silver one? Where do you get the black one?

Regards

Alec

[Thalestris24]

Hi Alec

You didn't lose any of the little washers then? ~00:09min in video . I think the black coupling/extension arm (not shown in your pic) is only used for R+P focusers - it should be a leftover (17:16). I seem to recall it's a good idea to check the motor to focuser connection is strong, step by step as you re-assemble. I guess it's the grub screw on the narrow part of the silver coupler that you have to be particularly certain is tight when you reassemble (~11:05 in video) (is that where you've drilled out the extra access hole in the housing, Alec?). Once the silver coupler is tightened to the shaft (13:27 in video) you shouldn't easily be able to turn the motor using the remaining focuser knob, but obviously that remaining knob should be tight on the shaft . As it mentions in the video, you shouldn't be using the manual adjustment once the motor is fitted. Lining up the bracket is a little fiddly.. (14:47). Don't forget to tighten the small grub screw on the knob side! ("that is your friend!" 16:12). Alec - I take it your initial testing went ok as at 18:00? The video misses out replacing the four little rubber washers/O-rings but obviously they should go back whence they came

Louise

[alcol620]

Hi Louise

Yes,  followed it all as per your comments and the video. Did have a moment today when 1 of the little O rings fell inside the scope body, moments of panic when it couldn't be seen, then managed to turn scope on end and it fell out - phew! Yes I have the black coupling as not required for the 80ED. I haven't drilled out any extra holes, but elongated 2 of them in the bracket that came with the motor so that the 2 grub screws to adjust the level of the neoprene washer on the focuser shaft. The bracket that came with the motor is not for the 80ED and the holes don't align, see 15.50 minutes frames in the video.

I am interested to know from anyone who has taken off the knurled coupling (with black grub screw) next to the motor, see my image above, as to what is inside it. Without undoing the grub screw that holds it onto the motor shaft,  it appears to be some sort of flexible coupling? I am reluctant to take it off to have a look as the producer of the video warns against its removal as its very difficult to refit!

Regards

Alec