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Argo Navis digital setting circles

A few weeks ago I got my digital setting circles for the EQ 6 mount, the Argo Navis DTC (Digital Telescope Computer), manufactured by Wildcard Innovations in Australia. The Argo Navis DTC has 29.000 objects in its

database. Some of its catalogues are: the complete NGC and Messier, non stellar selections from the IC, bright stars (a selection of stars to magnitude 6.5 with historical names, Bayer and / or Flamsteed identifiers), miscellaneous variable stars, miscellaneous double stars, the planets of our solar system, and miscellaneous selections from many other deepsky catalogues.

Setup of the Argo Navis
I ordered the Argo Navis and a set of encoders (8192 steps) for the EQ 6 from JMI. The package arrived in good order, and the installation of the encoders took me about 15 minutes. The only piece of equipment I used was a screwdriver (on the images below you see the RA and DEC encoders mounted on the EQ6). After the installation of the encoders I installed 4 AA 1.5V batteries to provide the internal power for the computer (you can order an external DC power cable to connect the Argo Navis to an external power source, like a 12V car battery). Finally, I connected the computer to the encoders using the encoder cables. I was ready to do the initial setup.

RA encoder

DEC encoder

After going through the initial setup (which you only have to do once and takes about half an hour) I started the alignment procedure. This procedure has to bee done every time you setup your telescope. The alignment procedure is very simple for the EQ6. Get the scope polar-aligned as exactly as possible. Then align the telescope on a star that you select from the alignment star list in the Argo Navis, and you are ready to go.

First run of the Argo Navis
After doing the alignment I gave the Argo Navis a first try.  To locate a certain object I first had to select it from the database. After confirming the selection, the LCD display showed two coordinates. I then simply moved the telescope along both the RA and DEC axis until both coordinates were zero. If I had aligned the telescope properly, the object should be in the field of view.

The first “run” was very satisfying. From the 9 objects I selected, only 2 where a just outside my 46’ field of view. I presume that with a more accurate polar-alignment the results will be even better.

First overall impression of the Argo Navis
The JMI set of encoders and cables were very easy to install. The 178-page manual (which you will find on a CD that comes with the Argo Navis) guides you through the initial setup and the alignment procedure. The database of 29000 objects (bright stars, double stars, variables and many thousands of deep sky objects) is really impressive. You can even add more than a thousand user objects, using the software and serial cable that comes with the Argo Navis DTC. The computer provides a wealth of details for every object within the database, for example M31:

M31, also known as NGC 224, Galaxy in Andromeda,
size=3.18 degrees x 1.03 degrees, mag=3.3, SB = 14.5
morph=SA(s)b, Andromeda Galaxy M31, very bright,
RA= 00:43:00, DEC = +41deg 17’35” above horizon,

The last data “SA=4” means that you find M31 in the SkyAtlas 2000 on map 4. You can change this into the Millennium Star Atlas or the Uranometria edition 1 chart numbers.

As you can see on the image below, the controls of the Argo Navis are very “basic”.

After you have switched the computer on you only have to operate two push buttons (exit and enter) and a big dial that lets you scroll through all the menus and catalogues. This is very convenient in the dark. The Argo Navis has an LCD-heater on board that enables you to use it in temperatures as low as -10 degrees Celsius (14 Fahrenheit). The LCD display size is 32 digits, 2 lines. You can set the scroll rate of the text and the brightness and contrast of the LCD display to your own likings.

Until now, I am very impressed by this small computer, but I will have to test it some more.  I will keep you updated about future results.

The Argo Navis on its mounting plate, attached to the EQ6

Posted by Math on 09/30 at 06:18 AM
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