Homebrew Motorising a CG5 mount
dby...@lineone.net
all the glue out of it and it's tracking like silk ! However, I'm
not keen on paying 135 pounds ($250-ish) for a basic RA motor from
Celestron, and I'm wondering if anyone's ever made up something
like this from normal bits'n'pieces. I imagine most small DC motors
would do the job, but I don't have any idea where to look for speed
control circuits. I imagine just lobbing a variable resistor in series
with a motor would run a fair chance of burning it out !
Any ideas or help appreciated,
David
Sent via Deja.com http://www.deja.com/
Before you buy.
Jeff DeTray
Hi David,
I've homebrewed a RA drive for my CG-5 mount. I used a small stepper motor I
found on AstroMart ($25), two Delrin Gears ($20), and homemade drive
electronics ($30). Total cost = $75, plus lots of my time.
Here's a look at the stepper motor in its approximate location before the gears
were installed:
http://www.detray.com/jeff/stepper/
It works well, except for a slight jitter that is visible over 100x. I need to
increase the step rate and add a corresponding gear reduction to smooth it out.
Tracking accuracy is good -- I've tracked for up to 30 minutes at 210x with no
visible movement of the object in the eyepiece.
The trick is finding a suitable stepper motor at a good price. My motor came
with a built-in 30:1 gear reduction that made it ideal.
The bottom line: it CAN be done, if you can find the parts.
--
Jeff DeTray | Wide-field Astrophotos
je...@detray.com | Barn Door Camera Mount
http://www.detray.com/jeff | Equatorial Mount Tutorial
| CG-5 Mount Improvements
Steve taylor
dby...@lineone.net wrote:
> I'd like to add a clock drive to my CG5 mount, now that I've got
> all the glue out of it and it's tracking like silk ! However, I'm
> not keen on paying 135 pounds ($250-ish) for a basic RA motor from
> Celestron, and I'm wondering if anyone's ever made up something
> like this from normal bits'n'pieces. I imagine most small DC motors
> would do the job, but I don't have any idea where to look for speed
> control circuits. I imagine just lobbing a variable resistor in series
> with a motor would run a fair chance of burning it out !
You want an AC motor or a stepping motor with a slightly variable AC drive
for this one. A Bog standard 12V AC motor can be driven with a very simple
circuit. I think you might get one from Bedford astronomical Supplies on
01706 815816.
Cheers.
Steve
Bruno B. Lobo
> A Bog standard 12V AC motor can be driven with a very simple
>circuit.
Any pointers to such a circuit? I, too, would be interested in
something like this.
--
Best regards,
Bruno B. Lobo
S 23 01' 16"
W 043 28' 19"
Warren Porter
Try this site http://www.efn.org/~mbartels/ He has a motorized dobs,
schematics, computer control. It seems a bit over kill for me, all I
want is to track reasonably well for visual use. His site has a bunch
of links to other sites as well. Try doing a web search for "saa1042"
That is an IC for controlling stepper motors, some interesting hits are
available from the simple to rather complex.
Warren
Jeff DeTray
>
>Steve,
>
>> A Bog standard 12V AC motor can be driven with a very simple
>>circuit.
>
>Any pointers to such a circuit? I, too, would be interested in
>something like this.
I've motorized the RA axis of my CG-5 mount with a small stepper motor. The
circuit for driving the motor is a modification of the one found here:
http://www.u-net.com/ph/mas/projects/scotch/scotch.htm
A more elaborate circuit for dual axis control using stepper motors can be
found here:
http://members.aol.com/drowesmi/dastep.html
The exact details of your circuit will depend on the step angle of your motor
and the gear reduction (if any) that you use.
--
Jeff DeTray | Wide-field Astrophotos
je...@detray.com | Barn Door Camera Mount
http://www.AstronomyBoy.com | Equatorial Mount Tutorial
| CG-5 Mount Improvements
Lee & Jane
FWIW, http://steppercontrol.com/index.html
There is a dll that can be modified for other purposes.
Lee
Steve taylor <St...@ravenfield.com> wrote in message
news:380DEB35...@ravenfield.com...
sco...@stny.rr.com
http://x27.deja.com/[ST_rn=md]/getdoc.xp?AN=533436356&CONTEXT=940505637.
72155241&hitnum=5
Check out the link provided ...basically an old IBM 5152 "graphics"
printer provides all the mechanical and electrical hardware to get you
in business. Software and documentation for running a PC as a controller
is provided. Stepper motors are geared down, and the timing belt for the
head traverse can be easily wrapped around an 8 inch disk for elevation
control. We are working on this project and will modify the software,
convert to C++, to be more specific to astronomy dual axis control.
As a side issue, I am looking into the feasability of using an
inexpensive quadrant dector mounted in a finder scope, to provide auto
tracking feedback to the PC.
http://x27.deja.com/[ST_rn=md]/getdoc.xp?AN=535777785&CONTEXT=940505637.
72155241&hitnum=4
Any electrical/mechanical/design enginneering assistance to either
project will be appreciated. Doesn't seem that many on this board like
getting their hand's dirty.
Stew Corman
Simon Mander
I am selling a celestron RA and DEC system with hand controller. About 120
quid, Its for the
Vixen SP mount. Dont know if it will work with your mount though.
Bruno B. Lobo
>Any pointers to such a circuit?
Warren and Jeff, thanks for the URLs.
Will tak a look right now.
Gary Sanford
>In article <380df63e...@192.192.14.12>, b...@altavista.nospam.net says...
>>
>>Steve,
>>
>>> A Bog standard 12V AC motor can be driven with a very simple
>>>circuit.
>>
>>Any pointers to such a circuit? I, too, would be interested in
>>something like this.
>
>
>I've motorized the RA axis of my CG-5 mount with a small stepper motor. The
>circuit for driving the motor is a modification of the one found here:
>http://www.u-net.com/ph/mas/projects/scotch/scotch.htm
>
>A more elaborate circuit for dual axis control using stepper motors can be
>found here:
>http://members.aol.com/drowesmi/dastep.html
>
>The exact details of your circuit will depend on the step angle of your motor
>and the gear reduction (if any) that you use.
FWIW.
Kits are available for driving stepper motors from:
www.mpja.com and
www.herbach.com
The saa1042 stepper driver IC is available from:
www.jameco.com
~~~~~~~~~~~~~~~~
Gary Sanford
Email here only:
sanf...@ibm.net
Steve
>
> Doesn't seem that many on this board like
> getting their hand's dirty.
>
> Stew Corman
>
Bollocks !
Try this then http://www.astronomycentre.org.uk/gallery/DomeprogPage.html
...but I'm not just poncing around with piddly little mounts !
;-)
Steve
Chris Heapy
>I started another thread like this a few weeks ago and got no responses.
>http://x27.deja.com/[ST_rn=md]/getdoc.xp?AN=533436356&CONTEXT=940505637.
>72155241&hitnum=5
>
>Check out the link provided ...basically an old IBM 5152 "graphics"
>printer provides all the mechanical and electrical hardware to get you
>in business. Software and documentation for running a PC as a controller
>is provided. Stepper motors are geared down, and the timing belt for the
>head traverse can be easily wrapped around an 8 inch disk for elevation
>control. We are working on this project and will modify the software,
>convert to C++, to be more specific to astronomy dual axis control.
>
>As a side issue, I am looking into the feasability of using an
>inexpensive quadrant dector mounted in a finder scope, to provide auto
>tracking feedback to the PC.
>http://x27.deja.com/[ST_rn=md]/getdoc.xp?AN=535777785&CONTEXT=940505637.
>72155241&hitnum=4
>
>Any electrical/mechanical/design enginneering assistance to either
>project will be appreciated. Doesn't seem that many on this board like
>getting their hand's dirty.
>
>Stew Corman
>
You haven't asked any specific questions. You've put a plausible idea
forward and said you're working on it, what sort of assistance do you
require? If you're asking if I think either plan is a practicable
approach I'd say 'probably not', but you could surprise me...
The ATM mailing list has plenty of experienced pairs of 'dirty hands',
and most have BTDTBTTS so you might want to kick your ideas around in
that forum.
Chris Heapy
Astro Ads: http://easyweb.easynet.co.uk/~chrish/aa-ads.htm * UK Astro Ads!
Astro Stuff: http://easyweb.easynet.co.uk/~chrish/lx200.htm * LX Accessories!
sco...@stny.rr.com
I am impressed ... your project is way out of my league ...I am into
piddly mounts with a minimal expense hobby project. If successful, I may
get a reasonable size mirror (ie 12 inch) and build my own dobsonion.
The challenge of tracking in two dimensions is what tweaks me.
BTW my refernce to quadrant detectors is pertinent ... go look up some
specs on "segemented detector" at UDT http://www.udt.com/home.htm
... as a servo element it can't be beat ...resoution better than
1:10,000 as compared to CCD at 1:500 ...it exemplifies the KISS
principle
Stew
>
> ...but I'm not just poncing around with piddly little mounts !
> ;-)
>
> Steve
>
>
sco...@stny.rr.com
thanks for your reply ...I'll clarify my "hands dirty" comment: I have
seen a fair number of individuals who grind mirrors, but most of the
posts if you scan through the titles are paraphrasing "what can I buy vs
what I have already bought". Tha't fine, just not my cup of tea.
I have a good understanding of classical bench optics and very
exotic equipment. As a test design engineer, I built my own lab at IBM
for 6 years in optical inspection and fiberoptics, and had equipment
most only dream about. We moved probes in .1 um increments and measured
them to fractional wavelengths of light. Want to know about
auto-collimators and precision alignment to arc-seconds??
I am having a time understanding the telescope paradigm, but do have a
background in macro and micro photography, so imaging/resolution is not
a foreign concept.
Check out my answer to Steve on the qudrant detector scenario.
As far as stating a specifc request ... I am not a EE and the circuitry
implementation part I am a rank novice in. We had support techs to do
this sort of stuff. The printer stepper motor is fairly straight forward
and the other contributer of our project is a professional programmer. A
PC interface guru would be nice to help with plugging the quad into the
PC for feedback control.
Stew Corman
>
> You haven't asked any specific questions. You've put a plausible idea
> forward and said you're working on it, what sort of assistance do you
> require? If you're asking if I think either plan is a practicable
> approach I'd say 'probably not', but you could surprise me...
>
> The ATM mailing list has plenty of experienced pairs of 'dirty hands',
> and most have BTDTBTTS so you might want to kick your ideas around in
> that forum.
>
> Chris Heapy
>
> Astro Ads: http://easyweb.easynet.co.uk/~chrish/aa-ads.htm * UK
Astro Ads!
> Astro Stuff: http://easyweb.easynet.co.uk/~chrish/lx200.htm * LX
Accessories!
>
Chris Heapy
>Chris,
>thanks for your reply ...I'll clarify my "hands dirty" comment: I have
>seen a fair number of individuals who grind mirrors, but most of the
>posts if you scan through the titles are paraphrasing "what can I buy vs
>what I have already bought". Tha't fine, just not my cup of tea.
That's always going to be true, most would rather look through
telescopes rather than build them.
>
>I have a good understanding of classical bench optics and very
>exotic equipment. As a test design engineer, I built my own lab at IBM
>for 6 years in optical inspection and fiberoptics, and had equipment
>most only dream about. We moved probes in .1 um increments and measured
>them to fractional wavelengths of light. Want to know about
>auto-collimators and precision alignment to arc-seconds??
>
High-tech stuff, but getting an excellent figure on a 12" mirror often
smacks of Black Art - it's amazing that experienced ATMs with very
modest equipment can succeed in producing a surface of equivalent
accuracy. It's also amazing how inventive ATMs are, often coming up
with their own unique solutions to complex problems through
consideration of the design requirements rather than resorting to
expensive technology.
> I am having a time understanding the telescope paradigm, but do have a
>background in macro and micro photography, so imaging/resolution is not
>a foreign concept.
>Check out my answer to Steve on the qudrant detector scenario.
I'm a bit puzzled what you are doing with that - is it a need to
autoguide for astrophotography? There's no other reason to use an
accurate drive system because for visual usage much larger errors are
acceptable. That said, you will need to correct in both RA and DEC,
and because of that your mount and drive mechanics will have to be
very good quality.
>
>As far as stating a specifc request ... I am not a EE and the circuitry
>implementation part I am a rank novice in. We had support techs to do
>this sort of stuff. The printer stepper motor is fairly straight forward
>and the other contributer of our project is a professional programmer. A
>PC interface guru would be nice to help with plugging the quad into the
>PC for feedback control.
>
>Stew Corman
That printer stepper motor is designed to move a piddly printer head
about 12" with reasonable accuracy, and vibration is not an issue. Not
quite the same as moving a heavy telescope (often not too well
balanced either) smoothly with extreme accuracy. As you said, you'll
need to gear it down substantially to get the required torque - if you
use compounded spur gears the demands on accuracy will be very high,
and the PE will be a nightmare. It will never be able to GOTO because
you won't be able to get the high-speed slewing from the high ratio
gearing you will have to use. A better system is to use a much more
substantial stepper motor and mico-step it, have the lowest ratio
gearing to the final drive as you can manage. If not that, then use a
DC servo motor with feedback mechanism to control speed because it has
a higher range of speeds within acceptible torque range (that's what I
used although I scrounged the feedback circuitry from a medical
infusion pump).
You don't want a PC in there unless it's doing something that's
otherwise indispensible (like running a planetariium program or
controlling a CCD camera). Better to keep it simple, and in practical
terms dragging a scope out on a soggy night is more pleasant without
having to set up a PC to make it go. A PIC with a discrete circuit
would do all you needed in this regard.
Of course, it depends on what you want to achieve. If it's amateur
astronomy you can have huge success with very simple equipment like a
manual Dob, high tech electronic drive systems are not essential. I
get no feeling of what you are trying to achieve and what the
application is - if you have a specifc aim (e.g., you want to make a
remotely-operable fully computerised mount to conduct an unattended
supernova search) then there may be an alternative approach and I
would have suggestions for you. If it's just a tracking drive system
there are established and workable solutions on the 'net. If you are
just experimenting with the technology then, well, go ahead and
experiment :)
sco...@stny.rr.com
I'll philosophize without addressing specific lines that you have amply
defined and I do appreciate your "devil's advocate" approach, as it
causes me to think.
First, I agree with you that experienced ATMs manage to get superb
results without the sophisticated high tech analytical equipment ... I
am simply trying to understand what they are doing as it relates to
classical optics ... I found the thread on artificial stars quite
facinating, but couldn't figure out why no one mentioned using mirrors
to fold the path. I was not implying that fancy techniques are required,
and you wouldn't believe how much "black magic" we did in the lab. I
built a Chesire type eyepiece this morning using a beam splitter from an
AO microscope side illuminator for my refractor which has a diagnal
mirror and is way out of whack. I need to place a flat mirror over the
primary to get any reflection.
Second, I am awed by photos of things that I truly believe you can't see
with visual observation, so for "photography" feeback motion control is
required, a monochrome CCD camera w/"c" mount ( have a Cohu ), to be
replaced by a digital camera in the future. Shots on the web of the
Andromeda (m31?) really get me excited. In order to have dual axis
feedback, a quadrant detector can zero to a single CCD pixel, visual
tracking comes as a bonus. BTW, for two star alignment it can't be beat,
since you choose two bright stars and are not depending upon crosshairs
for precision.
Fourth, haven't tried the printer gear train yet, so the slewing problem
has not been identified. When we implement on the existing 13 inch dob,
balance and center of gravity are key mechanical parameters. If
everything is plumb and centered, a single finger can move the hardware,
so the printer geartrain (which you can't stop by grabbing with your
hand) should be more than adequate. Having two axis dynamic PC control
is far easier than building a Poncet or equatorial table for polar
tracking of a sizeable dob.
Most of my viewing will be within 75 feet of the house, as I live on a
hilltop (some trees) a few miles out of town. A laptop can provide
portability to do the controlling and goto functions, the printer
circuirty can be powered from a battery pack, if an extension cord won't
do. I wasn't planning on remote viewing, but I know of a local
technocrat who does just that.
BTW, I am a tinkerer, and so far the build project is more stimulating
to me than the actual viewing ... but with the right experiences, I'm
sure that will change.
Thanks for your time and expertise in responding to my posts.
Stew Corman
Graham
sco...@stny.rr.com wrote in message <7ut72t$62q$1...@nnrp1.deja.com>...
<big snip>
> When we implement on the existing 13 inch dob,
>balance and center of gravity are key mechanical parameters. If
>everything is plumb and centered, a single finger can move the
hardware,
>so the printer geartrain (which you can't stop by grabbing with your
>hand) should be more than adequate. Having two axis dynamic PC control
>is far easier than building a Poncet or equatorial table for polar
>tracking of a sizeable dob.
<snip>
You'll need another motor to deal with field rotation on a Dob.
Or build an equatorial platform. I'm just finishing one and it was
easier than I thought and I haven't had to go outside to get parts
made.
I hope to have an article about my equatorial platform on my web
site shortly.
HTH
--
Graham W. D-I-Y Astro Projects, Digital & Film Camera Photos
WIMBORNE http://www.graham-wood.freeserve.co.uk/
Dorset Wessex Astronomical Society - Program, Location
UK http://www.wessex-astro-society.freeserve.co.uk/
Stephen Tonkin
>I found the thread on artificial stars quite
>facinating, but couldn't figure out why no one mentioned using mirrors
>to fold the path.
Lack of suitable mirrors?
Noctis Gaudia Carpe,
Stephen
--
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Steve taylor
sco...@stny.rr.com wrote:
> Steve,
> I am impressed ... your project is way out of my league ...I am into
> piddly mounts with a minimal expense hobby project. If successful, I may
> get a reasonable size mirror (ie 12 inch) and build my own dobsonion.
> The challenge of tracking in two dimensions is what tweaks me.
>
> BTW my refernce to quadrant detectors is pertinent ... go look up some
> specs on "segemented detector" at UDT http://www.udt.com/home.htm
> ... as a servo element it can't be beat ...resoution better than
> 1:10,000 as compared to CCD at 1:500 ...it exemplifies the KISS
> principle
What a good idea ! So good I'll nick it for one of ours
Stew, we need people like you, why not join and help out ? Once we have this
bloody dome done, we need to start on the scope. Current bets are on an
equatorial mounted 1 metre Ritchey-Chretien design, but that may change
soon. We already have a 30" mirror for a tryout of the mount. Apart from the
civil engineering, there is some serious instrument engineering for a AG
unit and camera system.
The Astronomy Centre has been around for far too long without any progress.
In the last twelve months or so I have shaken the whole thing by the scruff
of the neck and managed with a very small crew to get things rolling quickly
for the first time ever !
I hope you had a look at the last newsletter as well
Best regards
Steve Taylor
Kenn Lynch
I Just picked your thread (had gotten a bit tired of the debates in
SAA) I have a older Celestron Super Polaris mount with dual axis
motors and a controller. I also have a Sky Commander DSS
About a year ago I started to develop an AVR microcontroller interface
that would tie them all together with the aim of a self contained GOTO
mount with a PC.interface similar to the SS2K. Now in my case I did
have the motors already so the mechanical interface was fairly easy
(but limited as I'll explain,) I built a basic crystal controlled 3
axis (focus motor) controller. and while handling the basic movement
and driving at sidereal rate, I was never able to get anywhere near
the slew speeds required for a usable slewing with the stock motors.
It turns out it's difficult to get both the high resolution and speed
from a single stepper (separate slewing motors are often used in
commercial observatories mounts for just this reason)
I used a simplified "1" chip stepper controller the Alegro ULN5805?)
stepper that did none of the microstepping of the more sophisticated
controllers. (but does cut down the work and chip count) But to
squeeze the max speed out of a stepper you need good ramp up functions
and preferably current control instead of voltage. It also helps if
you have higher than 12 volts for microstepping so portability becomes
rather awkward or heavier at least.
While I only breadboarded this circuit It drove the steppers just
fine but is configured for the 300:1 Nipon motors used with the stock
controller. I could certainly burn you up an AVR controller chip for a
couple of bucks if you know the final ratio etc.
After that the whole thing should cost around $50 buck to assemble if
you shop around for parts.
What you might consider is that Joe Sensei at Earth and Sky was
selling the old Sky Sensor controllers and motors for around $100
http://www.astrosales.com/ (not sure if anymore)
This alone would hopefully give the you mounting kits and at least a
drive and motors (think they are 150:1)usable for visual work for
pretty cheap (Possibly at Astromart as well)
I am currently experimenting with interfacing a Meade Autostar
as a generic drive controller, I believe the accuracy of this driver
could be increased it was talking to better motors and encoders
My Autostar was second hand so it's definitely worth a try
But the info on the AutoStar /ETC interface is very scarce.
But all that said, I would still like to see If I can find a servo
motor solution to increase the slewing speed and interface to that
There is a group in Portugal (COAI?) that built what sounds like
a nice interface for the SP/GP but it requires a dedicated PC to run
it The price is reasonable at around $300 (certainly cheaper than an
SS2K at around $1200) but does assume you have the stock motors
Well sorry for babbling here but I just wanted to offer some help
as well as see what you come up with. I hope to reactivate my own
interest in this area very soon.
Kenn Lynch
On Tue, 28 Sep 1999 19:30:20 GMT, dby...@lineone.net wrote:
>I'd like to add a clock drive to my CG5 mount, now that I've got
>all the glue out of it and it's tracking like silk ! However, I'm
>not keen on paying 135 pounds ($250-ish) for a basic RA motor from
>Celestron, and I'm wondering if anyone's ever made up something
>like this from normal bits'n'pieces. I imagine most small DC motors
>would do the job, but I don't have any idea where to look for speed
>control circuits. I imagine just lobbing a variable resistor in series
>with a motor would run a fair chance of burning it out !
>
>Any ideas or help appreciated,
>
>David
>
>
>
Warren Porter
Have you looked at Mel Bartels controller? It is interfaced with a
computer. I have been considering it for use on an equatorial mount. The
thing is alot more precise than I want but is fairly inexpensive for the
populated board.
Warren
Kenn Lynch
Mel's controller does a wonderful and very sophisticated job of step
motor control. I would love to have the same level of features and
control, But unless I'm mistaken it requires a dedicated PC to
function down to the bit level via the parallel port. Only problem is
I do not want a dedicted PC system. I do want a PC interfacce
but only so I can optionally interfacce to Planatarium programs.
But Mels system is a great starting example But I want a to built
around an embedded microcontroller
Thanks
Kenn
On Tue, 26 Oct 1999 18:18:50 -0400, Warren Porter <wlpo...@erols.com>
wrote:
Stephen Tonkin
>Mel's controller does a wonderful and very sophisticated job of step
>motor control. I would love to have the same level of features and
>control, But unless I'm mistaken it requires a dedicated PC to
>function down to the bit level via the parallel port. Only problem is
>I do not want a dedicted PC system. I do want a PC interfacce
>but only so I can optionally interfacce to Planatarium programs.
Guide has an option to interface with Mel's AltAz system. I think I
recall reading somewhere that ECU does as well, but cannot verify that.
ed
>
> Actually yes a while back
> motor control. I would love to have the same level of features and
> control, But unless I'm mistaken it requires a dedicated PC to
> function down to the bit level via the parallel port. Only problem is
> I do not want a dedicted PC system. I do want a PC interfacce
> but only so I can optionally interfacce to Planatarium programs.
> around an embedded microcontroller
>
You could probably get away with some industrial small PCB-PC
there are plenty on the market, but pricing will beat a walk
along the garbage-cans and getting one for free.
There is an coupling with Guide as well as a grand tour feature.
So you just press a button to go to the next object, very close
to the solution you look for.
I don't have experience with it yet, but it seems a good option
for people with the GP (and clones), how might think it's for
a dob. Mel told me there are people on a Bartelized GP out in
the world. A collague of mine (thanks, martijn) donated me
a 386 Notebook to bartelize my systen, which solution is close to
an embedded system (It also has a nifty slot to store cigarettes in)
Happy gazing, Ed ( @ )
Ross Bench
What am I missing ??
Sir Sleepalot
wrote:
>Actually yes a while back
>Mel's controller does a wonderful and very sophisticated job of step
>motor control. I would love to have the same level of features and
>control, But unless I'm mistaken it requires a dedicated PC to
>function down to the bit level via the parallel port. Only problem is
>I do not want a dedicted PC system. I do want a PC interfacce
>but only so I can optionally interfacce to Planatarium programs.
>But Mels system is a great starting example But I want a to built
>around an embedded microcontroller
>
>Thanks
>Kenn
>
I noticed that the latest CPC catalogue has a new set of
products that you might find interesting ...
The key chip is called "Stamp" - it's a microcontroller
that runs basic (at 4,000 lines per sec.) (Stamp2 holds
500 lines of basic).
The development kit costs about £50 (I think - I haven't
got the catalogue here, it's at work) there's pc software,
a development board with a stamp chip, and manuals.
The stamp is programmed via a serial port, and can run
alone. It is reprogrammeable.
There are other support boards, one of which is a motor
speed controller - it all sounds ideal (to me).
Nope, I'm nowt to do with CPC. :)
(I was looking at it as the basis of a machine for
"robot wars". )
--
Sir Sleepalot aa#1385
Cut the string to email me.
Warren Porter
I don't recall all the links but I thought there were one or two for its
use on an equatorial. There is no reason for it not to work, the
initial alignment educates the program that your polar axis is nearly
north, depending on the precision of your polar alignment and
compensates for that fact. Thus once you are tracking or doing a go to
it it simply moves the axes appropriately. When tracking with a
perfectly aligned polar axis, the RA moves, the dec just sits there.
Warren
Kenn Lynch
And I know Mels interface is accepted by several Planetarium
Programs But what I am trying to build is an embedded processor system
(similar to but with more horsepower than the basic Stamp chip)
actually for about $300 the COAA's unit is very attractive but also
requires a dedicated PC and a parallel port Their unit is specifically
designed for the SP/GP mounts and the price isn't bad
http://www.ip.pt/coaa/ctc.htm
But basically what I want is a Sky Sensor 2K but at a lot lower
price. The best of both worlds to me is to have the basic Goto and
DSO functions in a portable handheld . (12 volt operation 2 or 4 line
display)
It shold also have the option of interfacing to a laptop via a common
protocol (LX200 "Ouranous" or Mels)
I can not see bringing two pcs or laptops to the field (one already
for the CCD) especially AC powered. This is of course only my opinion
and I know I would reconsider if had and observatory or permanant
site) I'm hoping to modify/adapt an Auostar! despite it's inacurracy
when used with an ETX it's really an impressive piece of hardware.
Thanks again
Skies...
Kenn
On Thu, 28 Oct 1999 07:28:01 +0100, Stephen Tonkin
<s...@nospam.demon.co.uk> wrote:
>Kenn Lynch <lyn...@erols.com> wrote:
>>Mel's controller does a wonderful and very sophisticated job of step
>>motor control. I would love to have the same level of features and
>>control, But unless I'm mistaken it requires a dedicated PC to
>>function down to the bit level via the parallel port. Only problem is
>>I do not want a dedicted PC system. I do want a PC interfacce
>>but only so I can optionally interfacce to Planatarium programs.
>