Dave Ek DSC Construction/Software/Usage     

coments mailto:cwhite1@jakeblaster.com

Background

While I like searching for objects in my 10" dob some of the dimmer objects sometimes take a little longer than I would like, on some evenings I would rather spend more time observing than hunting so I decided to put some encoders on the dob.

Dave Ek receives no compensation from either his widely used design or from Far Circuts which produces the PCB board based on his design or the PIC microprocessor code which he wrote. If you feel that you have received benefit from his hard work, support of those building and using the project, as well as continued development please consider making a donation directly on his website.

Please review the Dave Ek site before attempting this project. It has not only complete consruction information, resources, parts lists (which I did not reproduce, it's correct and up to date on his website) but, also theory on how everything works, this website's purpose is mearly to document MY attempts at construction, the suppliers/vendors, and any details I might be able to add along the way. The order in which I constructed my board does not match Dave Ek's suggested order, I had the 20 or so components laid out and just from habbit, went to town without really thinking to check if he had a particular order specified. You may want to follow Dave Ek's order but, you may find some of the photo's useful for orientation and identification of the correct orientation of certain componets.

Construction

In the following guide I will lay out the progress of the project in timeline style. Certain items may be dependant on a previous order for instance the encoder mounting hardware before I have the encoders (although the datasheets have all the specs) or ordering the extra components I need to complete the circut board before the FAR electronics package arrives. If you click on a particular link or date you will be taken to details of that particular construction phase, the supplier, or other details/photos of the project.

1/2/2007 I debated etching my own board and programming my own PIC, while I do have two PIC programmers and can get free 'samples' from Microchip I really wanted just to get the silkscreened board and programmed pic and not have to order a seperate oscillator from Mouser. So I went ahead sent in a fax order to FAR Circuts for the printed circut board, latest programmed PIC chip(it was not the latest version, see 1/14/2007 testing...), 4 MHz TTL crystal clock oscillator, and serial chip. The board and chips were $24 plus $2 shipping, because I faxed in my order with a credit card a $3 service charge was incurred for $29 total.

1/8/2007 Credit card was charged from Far Circuts indicating shipment. Far Circut's Fred Reimers has been around a pretty long time providing mostly ham related printed circut boards and is well respected for his work and service. But, he also will supply the PCB for Dave Ek's project along with programmed PIC, oscillator, and serial interface chip for $24.

1/10/2007 I received the package from Far Circuts. I would roll my own but, I hate drilling. No fragile parts were included, shipping was adaquate(padded mailer, widely used).
Click HERE for a description of the Far Circuts/Dave Ek DSC Product.

1/10/2007 I placed an order with Jameco for the rest of the components and hardware for the DSC rather late that evening, it later read shipped that evening. I don't have the cost's handy but, the components and hardware was not that expensive. Shipping is very reasonable $5.95 for first pound priority mail (I had 1000 feet of cable, the cable could be a couple pounds extra if you order it), I also did not order the $10 crimper, I have a few and to be honest it's easy to manage with a pair of needle nose plier's. You might be looking at around $20 in parts plus shipping without the crimper. I also ordered some extra LED's and other stuff I had on my list for another project. I did have a couple of the items, in fact I have maybe 5 pushbuttons now because I ordered the one suggested. You will have alot of extras once you get the order due to the order minimums(87 10k ohm resistors for instance).

1/10/2007 I placed an order for two S2 digial encoders via FAX from US Digital. CPR was 2000 so I had to pay the high resolution option for $61 each (incl shipping) for a total of $122. Correction shipping was and additional $10.72, it was added after I placed the order for UPS Ground shipping.

1/13/2007 I received my order from Jameco. Electronics suppliers including Jameco, Mouser, and Digikey are extremely fast. It came in a HUGE box with a bunch of extra crunched up paper. No fragile parts were included, shipping was overkill (I ordered priority mail, no tracking, incredibly fast delivery).
Click HERE for a description of the Jameco package.

1/13/2007 I picked out the components I needed and packaged them up
Details Here

1/13/2007 I mounted most of the components on the circut board.
Details Here - Construction of Circut Board

1/14/2007 First test of the board
Details Here - First test of the board

1/16/2007 Encoders from US Digital arrived
Packaging and encoder photos here

1/16/2007 Looking at Encoder Azimuth mounting pivot kits
Sent off an inquiry to Ed, looks like it's only $11.50 plus shipping at cost.
I first looked at the astrosystems.biz setup but, it's $25 + $9 shipping.

1/16/2007 Palm m135
I bought a Palm M135 a few years ago off of e-bay for $23 shipped, it was made in 2001 or so and I must have bought it around 2004 or so. I have a serial cable for it, I put in two new AAA batteries, formatted it, and loaded up PalmDSC for my primary DSC software along with the free version of astromist and tested out the serial connectivity and serial cable. I use astroplanner pretty frequently which will create PalmDSC files which is also one of the ideas for the DSC in the first place (just sounded like a fun project). The palm is black and white I don't really use it much I might cut a piece of rubylith and place it over the screen so I can use the backlight without objections. I wonder if the stylus will still work on the touch screen? I can always use it under a red light. Dave Ek's DSC will interface to quite a number of packages I have on my computer including my favorite Cartes Du Ciel but, I think I will still just stick with the PALM.

1/23/2007 Azimuth pivot Kit
Call me impatient but, on 1/18 after getting no response from Ed, I placed an order for a much more expensive kit, received a response from 1/19 from Randy that is was shipping on the 20th. Both the kit and shipping are signficantly higher (as well as the quality and keep in mind this will be holding your rocker box together), if I get a response from Ed I will see what we can do as Ed's kit appear more suited to the smaller dob like mine. I have also run across a couple of links of people who made thier own (although they were links from Dave Ek's site). I received the package on the 26th. The total was $25 + $9 = $34, more than the initial board and chips. You might be better of planning your own solution or try and get Ed's kit @tscope's.com (for a smaller sized dob like mine it looks like a good solution).

1/23/2007 The ground board and base of my dob is both 5/8" with between 1/8" and 3/8" in-between. I may have to raise the dob base in order to fit the encoder, the encoder cannot be placed on the bottom, while the dob has casters and is well above ground the cable would twist around and around. It would be a problem but, not one that I would not be able to get around, I considered this at the beginning of the project but, never had the need to take the measurements until I reached this phase of the project.

1/26/2007 I received the Azimuth Pivot Kit from Astrosystems. It was pretty pricy$$ The total was $25 + $9 = $34, more than the initial board and chips. You might be better of planning your own solution or try and get Ed's kit @tscope's.com (for a smaller sized dob like mine it looks like a good solution). But, it's recommended on the tscopes.com website for larger scopes.

1/28/2007 Looked more closely at the encoder placements again.

1/28/2007 Put together an encoder cable

1/29/2007 Could not sleep so I did the first part of the Atz encoder

1/29/2007 I shot Fred at Far Circuts off a note stating why I thought I had an old version of the PIC code, he replied immediately saying he would mail a replacement tommorow(I sure hope I did'nt make a mistake but, every indication is that it's the older version).