The simple system - switches electrically at
controller
Basically, Dual Axis Electronics are very good system with free stop at
Losmandy GM-8 or G11. However, PEC setting is little bit painful because
have to patient 8 minutes with keep looking guide star on reticle eyepiece.
One day, one of my acquaintance suggested to me "maybe possible to use the
AGA-1 which you already have". Then I started to think about it. Because,
yes I have AGA-1 and it already dead stock because not using VIXEN GP mount
with DD-1. It was not perfect because Orion UK 300mm f4 reflector is
little bit overweight for GP mount. If I can use AGA-1 on Losmandy GM-8, then it will
be realize the automatic PEC input.
If possible, of course I'd like to use SBIG STV
or SkyWalker-Servo by Astrometric Instruments.
However, until ready to buy, use AGA-1 temporally is not bad idea because I
already have it.
So I started to think about it but, no information are available to do
it. I have no idea how to make it change at first. One of the web site shown
pinpoints for connect Vixen SkySensor2000 and SBIG ST-4. Losmandy is ready
to use with ST-4 then I felt possibly works as this and tried to do. But
not. Thing are not so easy.
Kept thinking about it a couple of days. Finally, I felt "why Vixen requires modify the DD-1 controller box?" and opened up the DD-1. Cables are solder to the each control button's solder points (photo above left). Might be same way works. So I decided to try to solder the wires at inside Losmandy's control box as same as this.
 Material
- Wire Stripper and Soldering iron
Losmandy controller connected by RJ-12 (RJ-11 phone plug is 4 pins and 12
has 6 pins) which uses for ISDN at Western world (different
with Japanese ISDN). To do
this modify, you need modular jack tool with wire stripper. At my case, one
of the friend of mine has it then I could borrow. Have to have a good
friend.
Peel the wire both side out then set the modular jack at one side. Solder
the other side at inside control box. Losmandy's control box has cable hole
large enough to out two cables then not necessary to make wire hole larger.
AGA-1's pinpoints shown right and where each wire sold up is shown as
picture below. (If you do not get this, do not do it by yourself. I do not
take any responsibility about all of your problem.)
 
It Worked!! It's a time to think about guide scope, now.
The time like this, we had typhoon in Japan next and next then bad weather
continued. So I could not test the result. Finally, one of the night comes.
Put WAT-100N video camera to the Orion's focuser. Settled with AGA-1 and
started PEC setting. It working!!! I made sure Modified Losmandy worked very
fine with AGA-1 not only setting the PEC but also follow the star as a
auto-guider. Just one point how to use is, set Losmandy's speed 2 positions
of slower which works after PEC settled. Because it moves too fast by
AGA-1's signal.
Now it is a time to think about guide scope. I have to make it as light as
possible. I already have
BORG76ED and BORG's new product miniBorg makes it
lighter because use miniBorg's unit instead it's heavy
focusing helicoids unit with slits. I've
got unit and adapter of miniBorg50 additionally. This gives me minimum
investment to get maximum result.
To mount the scope on Orion, used
Mizar's Video-astro-plate's VX86 ring
because I already had this too and it is very light weight more than any
guide scope mount. Also it is stable fitting because two legs.
 After
done several things, no hesitate to drill the telescope tube. To fitting the
flat bottom of the VX86 ring on tube, rubber spacer works very fine. After
tighten them up by bolt and nut, paint the bolt head as flat black at inside
tube. It looks good, isn't it? (photo left)
So, system is ready to use but not used yet because still bad weather
continues. But, if good weather continues, maybe I do not had time to done
this modify, right? This work was so great to smash my time under the cloudy
nights.
Digression - the tuff part of auto guiding
Needless to say, the tuff part of the auto guiding is "bring guide star into
scope". The answers are...
- Let make system possible to use guide star as dark as possible.
- Let use off-axis guider.
but these are so far to me. Because I have so bright night at Kobe City.
Just "anyway look for the star near by then bring them
in to the guide scope" is everything what I can do. I've tried to the
image-shifter (by BORG) or stir mount but nothing perfect. I think VX ring
is a kind of best idea at this moment.
AGA-1 make things easier to use without side-by-side computer. It
is very comfortable to me. If want to be perfect, all items comes more
heavier and system requires larger mount. Not only cost me like endless sky
but also heavy stuff makes me hesitate to set it up each night again and
again. However, make observatory on my property is nonsense because too
bright night in the City. I'd like to keep my stuff lighter.
Daisuke Tomiyasu (Sept. 3, 2004) |
