Hi Ryan,
You can have a spare board, no problems.
If anyone else is interested in doing the build please let me know now as there may be more spare boards.
There are two small issues with this PCB and both can be easily overcome:
- One capacitor is not in the right place and that this is causing noise. This was solved by scraping off the soldermask from one track and soldering the capacitor onto the scraped section, to move it. Not a big issue.
- Somehow the silkscreen only partially got printed on the boards so you will need to have a paper printout while soldering to see which part goes where.
Definitely not worth redoing the PCBs because of this.
I can also help you with some capacitors/resistors. Some cost only few cent but they are sold only in bulk packs, for example in packs of 100. This makes the cost per unit expensive (few $) when you really need only one or two. And there are several parts like this so it does add up quickly.
My BOM should be a good starting point and it has Element14 and RS components part numbers for most of parts. The stock levels are not accurate but you should be able to see what I have bought in bulk packs (marked in orange). Some parts have to be bough on ebay and it may take several weeks to arrive. The sensor comes from a donor Nikon D40, D50, D70 or D70s (not D40x!!!). Broken cameras on ebay can be bought quite cheaply if you are patient and the sensors from those cameras are usually fine.
Also consider getting spare parts (I got spares for the cheaper parts). For example, cam90 uses most of the same parts so if we ever go that way...
Did you buy your scope in Perth from a proper astro shop? If yes, which one? All the stores I know of are in the Eastern states so anything local certainly may have advantages.
Regarding using the heat from TEC to deal with dew, there are two main issues. One is the extra weight and the other one is the rigidity of the pipes. Also you get no dew control if you are not running the camera. Furthermore, without a pump there may not be enough cooling for the camera. Glen (glend from IIS) experimented with water cooling for his cold finger modded DSLR (with pump on the ground) and found out that the pipes are quite difficult to deal with.
The usual way to deal with the dew are heating tapes. I made mine with Nichrome wire (Jaycar stocks them) and duct tape. Resistor ladder is another way. There are plenty of recipes on google and they are really easy to make. There are also lots of ways to build a power supply, check the DIY forums on IIS. Mine is roughly based on Chris' idea from
here. There are lots and lots of options, again, google is your friend. You could also get a cheap adjustable power supply and manually control the heating power.
But really the last few nights were quite extreme in humidity. Usually in summer there is hardly ever any dew here in Perth but you will need definitely something for the winter.
Another DIY project for you
Unfortunately there is no good viewing so close to the city as there is too much light pollution. Part of my motivation for this build is narrowband imaging which can be done from light-polluted areas. I'll definitely take you up on the offer to find darker skies but will need to sort out few issues with my mount. Also ATM I am using mains power in my backyard but moving to a darker skies will require portable power source of some sort. You will eventually also need something, for the camera and for the heating tapes to start with.
Again, if anyone else is interested in doing the build please let me know now as there may be more spare boards.