theropod

My Arduino based barn door tracker runs on an Arduino sketch with less than 16 lines of code. Don’t fear the reaper! Seriously, the code for driving a single stepper is super simple, but it is designed for the Easy Driver hat just sends a pulse stream. The “secret” to making an Arduino precisely time those pulses is using the “millis” feature instead of the “delay”.

Old fart story warning: My oldest brother was the crew chief on a top fuel dragster (rail) that contended very well here in the USA back in the late 60’s. We talked about the toothed belt driving those huge supercharged engines more than once. His take on the issue that a little too loose was far better than a little too tight. He also said they put a new supercharger belt on with each rebuild of the engine, which was about 6-10 runs. Granted, your mount isn’t cranking >1500 HP, but I would think the same principles are at work. Your old belt looks like it suffered from cord breakdown. A little too tight and those strings in belts give up.

Idea: Use a multi faceted dome-like structure with dozens of iPhone type cameras overlapping each other’s field of view to capture an all-sky panoramic effect. Feed these images into a powerful system that would automatically stitch the individual images into a projectable planetarium-like view, or VR feed. This multiple camera approach could provide higher resolution capture than using single wide angle lenses and delicate exposure balances.

I had one of those active ice chests running on 12v DC. It did work, but not well. If I filled it with already cold stuff, and filled the voids with ice, the active cooling would keep ice far longer than would otherwise be the case. It would freeze a lump in the immediate area around the cooling plate IF it was being fed slightly higher voltage than a resting battery (when it was attached to my running vehicle). That 14ish volts over 12 volts seemed to make a big difference.

I lightly painted 600 grit black wet/dry sandpaper, cut a long tube out with an exacto and steel rule, curled up and ever-so-carefully slid into the final focal wall tube of my C-90 killed 95% of the bright target side-glare, like Jupiter just off the FOV, and a dead black dew shield helped even more (a combo of self stick flocking with flat black paint). Killing those side light reflections somehow improves contrast, or maybe fools my eye, because even my little scope was markedly improved by blacking out as much stray light as possible. How much is to be gained from opening it up, not going to push it. I see no reason the same effect cannot scale up with overall APO diameter. Make ‘em black holes inside. If it’s not a lens/mirror it’s black! These scopes just need to be a little easier to pop apart and back together, for the very reasons outlined in the OP. Getting back together right is absolutely critical.

Called it! Those are some nice sharp moon photos. Just think if the ancients had a scope like yours.

Good work! I assume the collimation came right back to “right”. I imagine the flocking will really make the mak shine, pardon the pun. Side-glare (now removed), when viewing Jupiter for example, will make contrast superb. If I were you I would be prepared for greatly improved views. Some fuzzies won’t be as fuzzy, and something like the GRS (great red spot) will just seem more pure (depending on the skies of course). If you now made a dew shield/light trap about as long as the OTA, made sure the focal tube was flattened and using a good EP your scope would become the little engine that could. I love maks!

To me, the issue with this fault is the component labels are burned away. Unless a schematic can be had that lists which part is what, or a known working example can be used for reference/comparison, it might be next to impossible to make repairs no matter how the traces are fixed.

One method to “fix” burned out, or otherwise ruined, circuit traces is to replace them with single strands of copper wire following the EXACT path. This can be done by following the trace to the next component/pin, carefully soldering from one source to another. Test that the wire is conducting properly, and then use enamel varnish to secure the wire to the board. “Magnet wire” found in all diameters, works very well for this as it already has an insulated coating, and only requires a thin coat of adhesive to secure it to the board. Of course this wire must be bent to match the trace, and be of the same length. Magnet wire will need to have the tips striped of the insulation, but careful scraping with an exacto will do a fine job. Otherwise the wire will not accept soldering. Sometimes a trace can be exposed with an exacto far enough away from the damaged area to avoid a long run, and the new jumper wire soldered to this “fresh” trace point. Careful work can remove the insulation overcoat on the trace and provide a solid point without lifting it from the substrate. All this being said the real issue becomes the downstream components that may have had the magic smoke released when the fault happened. One failed component could have caused a cascade of failures across the board. I’ve fixed surface mount voltage regulators using this hack, but it requires patience and a magnifying work light is a big help.

I’ve considered pouring a concrete observational pad several times, and I have the space for it. I was thinking that such a slab could “float” on a thick layer of coarse sand. If the sand was drained well so that precipitation wouldn’t “stand” under the slab there should be little, if any, heaving with freezing temperatures. My thinking is that such a “floating” slab would absorb vibrations more fully than if the pad were in direct contact with the packed earth underneath. Am I overthinking the issue? Sorry for the thread hijacking.

Consider the Celestron C-90 mak as it has a lifetime warranty. With a little careful flocking and a long dew/stray light shield it can provide some stupid crisp views. I love mine, but a twin of the Hubble would be practically useless around here as perpetual cloudiness has hung around for months!

Oh my, that’s WAY over the top for this tiny little scope project. I think the focuser cost me $12.50 off eBay, and the 60mm objective was free as the binoculars were given to me before I drove over them with my pickup (they fell off the bed I had laid them on in an absent minded moment). This is just a make work project, and maybe practice of I find a larger objective lens in the future. I’ll probably give this away in the end, but I want to test it on my DIY alt/az stepper driven mount. I expect the finished weight with EP to be under a pound, and on that mount should really shine. The FL of the objective is less than 6”, and whatever I settle on won’t be a bank breaker, so a hunk of carbon fiber tube that short might not be prohibitive. I’ll look into it. I wouldn’t even be bothering with this if the objective was junk, but apparently the majority of the cost of the binoculars was tied up in that front glass. Before removing the lens from its tapered housing I jerry-rigged a PVC adapter to hold my 1 1/4” 12.5mm, and the views were awesome. Getting the prisms out of the path really helped a lot. No CA even on a full moon, and Andromeda just fit in the FOV, and crisp as could be.

OK, that’s impressive. Now the search for AL tube begins!

Hi all, I am thinking of turning a wooden form upon which to lay down fiberglass mat to make the main tube for a small refractor. I have a nice 60mm objective salvaged from a set of hopelessly broken binoculars. I bought an inexpensive 1 1/4” rack and pinion focuser with a 2” tube attachment point. Since I know the focal length of the objective wouldn’t turning down a closed grain hardwood mandrel/form work for laying down multiple layers of fiberglass? If I smooth out the mandrel, with appropriate tapering from 60mm to 2”, shouldn’t that work? I’m also thinking a good layer of car wax would allow the fiberglass to release after curing. I could make the form in 3 pieces. Imagine two main halves divided by a slat that could be removed and allow the form to collapse. If I made extended pieces on the form where I could place automotive radiator hose clamps to hold everything together I cannot see why it wouldn’t work. Should I think about inserts to strengthen the objective cell mount point l, and the focuser’s? Should I just go buy some PVC plumbing parts and make that work?

Don’t talk to me about clouds. We have had a total of 4 semi clear nights since January first. Two of those were during the full, or near full, moon phases. I’m not suggesting that PA is a requisite, but rather a plus if a long night of looking at just a few targets, or one, is the idea.

While not a prerequisite for visual use proper alignment can make the experience more relaxing. I have spent a whole evening looking at Jupiter, for example, and not having to fiddle with the scope makes it pretty nice.

PepeChambo, Looks like you caught a small meteor too. Excellent work! It’s been cloudy and or raining for 18 days, and nights, straight here in north central Arkansas, and it’s expected to go on like this for at least 8 more days. Maybe a sucker hole will open up and I can at least get a glimpse of both this one and PanStars before the show is over. Maybe...

Oh, I have an iOptron SkyTracker Pro, which I absolutely love. I just built the barn door(s) to learn something and see if I could. I didn’t have a clue about drift alignment before building one, so there’s a big lesson right there. I also cut my Arduino “teeth” on understanding how to generate accurate step pulses of the right speed and duration, which helped a great deal when I built my joystick controlled Alt/Az mount. I’m now attempting to learn wireless communication using two Arduinos and those super cheap NRF24L01 wifi modules so I can tilt/spin that little Alt/Az mount without touching it. If I can get that working another add on will be a wirelss focus control. So, what began as a simple barn door tracker has branched off in several directions. Stuff like this keeps my mind, and hands, useful.

Yes, earth’s first life was anaerobic. No debate there. The point I was trying to make is that until this complex anaerobic life form was discovered there has never been any evidence that such life forms had achieved complexity, or could. Indeed this seems to be a case of a previous oxygen metabolic organism that adapted/evolved an anaerobic metabolism.

Some online sellers also collect ad revenue derived from “hits” to their site whether a purchase is made or not. If that means misleading a customer by listing unavailable items so a Google search drives them to their site still makes them money. Even more disgusting is a trend for web designers is to creat pages with hundreds of hidden “keywords” or “tags” that search engines use, and said pages have nothing but dozens of ads, and not one iota of relevant content. I encountered four such sites yesterday while searching for Arduino code to enable a wifi driven remote control lawn mower. It seems the more obscure the search parameters the more likely one is to encounter this.

With the recent discovery of a complex life form right here on earth that has an anaerobic metabolic system exobiologist now have yet more places to look for alien life. While this recently discovered life form is secondarily anaerobic, meaning it adapted to this metabolic system, it doesn’t rule out such a possibility on an alien world. Here’s what I mean: Suppose life arises on an alien world where oxygen is present, but over millions of years said oxygen is somehow gradually lost. Those alien oxygen dependent life forms would either adapt or become extinct. The fact that such an adaptation happened here, where no such lack of oxygen exists, it can happen anywhere. This opens the door to a wider search of places where we might otherwise jump to the conclusion that life couldn’t exist because of an oxygen. ”Life finds a way” is just a fact.

Have you contacted iOptron? This sounds exactly what their customer service department is for. All my experience with iOptron service has been top quality.

I think you ought to give building one a try. It really isn’t hard to bend a threaded rod fairly accurately with minimal tooling. A junk ink jet printer can supply a little stepper motor and often a set of reduction gears can also be found. Sometimes a high count optical encoder can be found, which is a big deal. A $2 Attiny85 8 bit 8 pin DIP, which works like a small Arduino, can supply precise pulses for a stepper motor driver board, like the Big Easy, and sip power. That driver board, among others, can microstep the motor to both smooth out the step pulses and provide high RPM/steps per minute accuracy With a very short sketch/program (<20 lines of code) and simple parts a good bran door can be built for $20, with scrounging. A high quality hinge is the most important part, IMO. If one finds, or makes, a disc of the same diameter as that of the curve in the rod one can keep at it until the rod lies perfectly all along the curve of the disc. A 14” pipe would be nearly perfect. Maybe wrap masking tape around it 1/4” thick to bring the center of the rod out to the 14 7/16” away from the hinge, or cut a plywood circle with a router. Brass rod is easier to work than mild steel, but not as durable. Remember, you aren’t building a Losmandy here, and perfection isn’t possible. Mine works great if I drift align it, and didn’t even bother with an alignment scope/tube. I just set it to Polaris along the hinge to start, and then pick out a couple stars to use as drift checks. When I buckle down and get that right I can get 10 minute wide field shots that are pretty darned crisp.

I just put the breakers on the positive lead of each 12V pair, which all the positive leads and negative leads attach to positive and negative 1/2” x 1” X 42” solid copper bus bars. Those bus bars reside behind the batteries in a divided compartment of the box, and a 3” plumbing fitting allows cable access to the outside world. The inverter/ charger, solar charge control and wind (aside from a dump load for the wind) all are fed via these bus bars. All the cable, batteries and bus bars live in a locking thick steel decommissioned Union Pacific railroad crossing control box, and this is all positively ventilated to get rid of hydrogen gas produced from charging the lead/acid batteries. The inverter and solar charge controller live outside that box in their own double dry screened in box about the size of an apartment size fridge. The chances of water intrusion into either box is nil. No bugs or rodents have ever caused any issues with the electrical system itself, but yellow and black paper wasps have found the rain drip rail over the top of that steel box to be “just right” for them to set up shop. That box sits under the protection of a small shed, and never sees full sun. I have to deal with at least one new nest of the beasties every spring. TMI?

Having lived off the grid for 20 years, and using a bank of multiple 12V lead-acid batteries I can attest that operating such batteries in parallel is common practice. We currently have 16 6V golf cart batteries wired into 8 pairs of 12V batteries providing somewhere north of 1400 amp hours of capacity. Fusing is more critical than diodes, which are power wasting little devils. A 50 amp breaker protects each positive lead of a 12V pair.