EQ8 Mount Home Position

[Chunky Wheeler]

The other night I had an annoying experience with my EQ8.

I was nicely set up and centring on a galaxy when the cable for the hand controller fell out. Probably because I was pulling on it too hard--it's way too short for my set up. Anyhow, I plugged the cable back in the control box without first turning off the mount (silly me).

The first message which came up was " do you want to auto-home?" and like a fool I pressed yes. It then auto-homed 180 degrees from where the home position is and did this for the rest of the night, in between behaving very strangely, despite the fact that I manually returned it to the old and correct home position, and repeated the 2 star alignment a few times.

I am not sure but I think the only way to get out of this dilemma is to Restore Factory Settings.

Has anyone got any advice?

Secondly, does anyone know where I can buy a longer cable or better still a wireless hand controller?

Thanks a million, Chunky

[doppler]

I just use a cat5 network cable for my HEQ5 pro hand set. I think that the Neq6 had a serial connection on the mount end but the azeq6 and later went back to the cat 5/6 connector on both ends.
For wireless connection there is this http://skywatcheraustralia.com.au/product/wifi-adapter/

[AndrewJ]

Gday Chris

The home positions are set using a fixed semicircular disk fixed to the axle.
It only has one position for home ( based on the way it blocks/clears a sensor ) and as such, either the disk is mounted 180deg out, or your perception of "home" has been wrong for a while.

Andrew

[Merlin66]

Chris,
Like the others I use a CAT5 cable to connect the hand controller to the HEQ5 mount.
On the NEQ6, yes it has the DB9 connector on the mount. (I use an EQDIR adaptor and EQMod to control it)

[Chunky Wheeler]

Thanks for your prompt reply Andrew.

I have operated this mount successfully for a couple of years and the normal 'Home' position has always been due south, scope pointing at the SCP, unless I have used a custom position. This time it decided that 'home' position was due north with the scope pointing at the floor.

It seems to me as if when finding home position, the mount chose a location closest to where the scope was pointing at the time, which was northwards.

I shall refresh my perception of home position by reading the manual. I shall be surprised if I am absolutely and terribly, terribly wrong!
Chris:)

[Chunky Wheeler]

Thanks for that tip. If all else fails, I'll give it a try. I see that Shoestring sell longer cables for Synscan hand controllers--but not directly to customers in Australia. I shall try Bintel.
Chunky

[Chunky Wheeler]

Thanks for that. Yes. I had taken a look at these this morning. Not sure if I want to use my phone to control my mount---the old eyesight is not as good as it used to be, and may be the detail is a little hard in the dark. Nice to feel the buttons of the hand controller!
But I will download the app for doing so and see how clear it is.
Chunky

[AndrewJ]

Gday Chris
\
Thats 100% correct :thumbsup:,
but there are 2 "mechanical" ways to achieve that if you are "manually" putting the scope in that position :-)
There is only one way if the mount uses its internal sensors.

Nope, it chose a spot where its internal home detection system said the internal sensor changed state.
Simplest solution is to do an auto home via the handbox
If scope is pointing wrong way ( as yours is ), undo DEC dovetail clamps and rotate scope 180deg and refit.
All should be well after that.
The encoders are reset on every boot, ie they have no real idea where they are until you align or home, but the home sensors are mechanically fixed.
( Also note the "mechanical" home sensors arent fitted very accurately,
so even after using the "Find home" functions, you could still be off by several degrees )

Andrew

[Chunky Wheeler]

The Mount instruction book says the mount is equipped with two home position sensors. The Syncan Instruction Book says Home Position can be in either of two positions--the North or South.

After the mount had pointed north at the ground, I unclamped it and put it back in the South home position manually. I them auto homed, and it went back to the ground pointing north position. I avoided doing this next time by not auto homing it--but then its pointing accuracy was very poor.
Disinclined to unclamp and rotate scope by 180 deg Andrew. I think this would bring me another bucketful of problems!

Won't be able to get out to my setup until next month, so not much I can do right now except ask questions.
Thanks for your help Andrew and by all means let me have any more ideas.
Chunky

[Chunky Wheeler]

Thanks for that. I have had a look at the $99 wireless receiver and have downloaded the App onto my Ipad Mini. Its looking good. Now all I need to do is to double my data allowance from Bigpond........

[AndrewJ]

Gday Chris


Do they mention hemisphere differences?????
"Home" is the OTA pointing at the pole, so thats all you need to know.
If autohome sets your current setup pointing North and down
then you have the OTA mounted in the DEC puck 180 deg out.


Then ( AFAIK ) it wont work using the handbox homing routine.
As i mentioned, there are 2 positions of the DEC puck where the dovetail bar can point at the pole.
As a human, you can point your OTA to the pole no probs
but the mount cant.
Andrew

[Chunky Wheeler]

I am not sure if we are talking at cross purposes because I don't quite understand what you are saying. The mount has worked perfectly well for the last couple of years in the current configuration of the scopes 'home position'. Why is it then necessary to de-clamp and rotate the scope? What's wrong with simply restoring factory defaults?
Thanks, Chunky

[doppler]

If you are using wifi you won't be using any phone/internet network data allowance.
I see that there is also an app for windows so you can control the mount from a laptop....wireless is good if it can be fully utilized....mmm another update looming?

[AndrewJ]

Gday Chunky
What i am saying is if "you" ( a human ) put the scopes DEC axle in home position manually ( ie OTA pointing at the pole ), there are 2 positions you can do it, and both will work correctly if you then do an align.
If you rely on the home "sensors" to find home, there is only one position.
If in the past you have set home manually all the time, then it will always work, but if your current home is opposite to the sensors idea of home, then auto homing via the Hbx wont work.
There are no "factory defaults" for the home position, it is mechanically set by the semicircular disk on the axle.
There are 2 possible "software based" home positions, but these rely totally on someone telling the hbx the mount is in the correct position at the start of an align.

Andrew

[LewisM]

No you don't - the Wifi connection does not use any internet/ISP - it is merely a Wifi radio signal via DHCP between the iPad/app and the mount. Nothing whatsoever to do with internet or data at all.

[PeterM]

Chris we will sort it out next month. Undo the clutches point the mount and tube to about the SCP then lock them. Turn the mount on then undo both clutches and then physically moving the scope to a (bright) known star, centre it, lock the clutches then sync the mount on the star and it should be fine (if its Polar aligned and I know yours is). You only need the one star.

[Chunky Wheeler]

Thanks for that note Peter, and your phone call. I shall follow your advice when next at my mount.
Interestingly, I contacted Skywatcher to get their advice and they really didn't have anything meaty to say. They did suggest Restore Factory Settings, but it seems that Andrew thinks this will have no bearing on the problem. After your advice, I don't need to bother with it now anyway.

Sky Watcher do not supply a longer cable for the hand controller so the two alternatives are a CAT cable--which I already have--and the wifi adapter, which I shall buy. Wireless has to be the way to go. Pity everything else is not wireless. It would save a lot of snags.

[Chunky Wheeler]

Well, I have learnt something. Thanks a million.

[Chunky Wheeler]

Thanks for that Andrew. In the past, where the scope has not been safely parked in a custom parking position, I have set the home position manually, and then auto-homed after turning the mount on. A belt and braces approach you may say. The mount/scope was facing due south in each case of course.
In the situation under discussion, the scope/mount was facing northish when I auto-homed. This upset the apple cart.
But now I know how to fix it, I am a happy chappie.
Best wishes.

[AndrewJ]

Gday Chunky

Do you remove/refit the OTA each setup like that?????
If not then the above sounds odd????
I know there was a bug in the Autohome routine where it didnt find home, but not where it was 180deg out.
( I spent a few months working with some users to devise a new PC based autohome routine, so do know how it is "supposed" to work, but in this game reality trumps theory every time :shrug: )
Ref attached piccy of the home sensor
The way homing works is the mount looks at the current sensor status ( ie blocked or open )
Using that to decide initial direction, it then moves until the sensor trips.
It then moves a set distance in a negative direction from home
and then moves in a positive ( fixed ) direction at slow speed
and waits till the sensor changes from say blocked to open.
That is declared Home
If the puck is 180deg out on that first rough slew, the final transition would be open to blocked for the same axis direction and it would fail.

The bug mainly manifested itself if you were close to home when you rehomed.
If you want to use the autohome, you really should start with the DEC at say 10deg off home, but its all irrelevant if you are physically at the mount, as you can probably set it closer manually :D

Andrew

[Chunky Wheeler]

The mount with scope attached are always parked after use and live in a permanent observatory.
Thanks for your help Andrew.
Best wishes,
Chunky

[AndrewJ]

Gday Chris
To me, the only time Autohome would ever be used is after a power loss at a remote location and you dont have a webcam view of the scope to recover it to the rough home position manually.
In that case, you need to ensure the OTA is setup correctly to match the mounts mechanical home sensor.

If you manually set home for the first align and always park, then the Autohome routine never really comes into it.

Andrew