Astro-Geek

..That went down well... 🙂 I've found a work-around however. My main wish to be able to run other planetarium applications through the SkyFi III was to enable me to use it through my PC, as well as my Android tablet. ...because SkySafari only runs on Android and IOS. I've now discovered that my Android emulator on my PC (Bluestacks), runs SkySafari perfectly and connects to the SkyFi via wifi with no problems. As it's also happy to run in a window alongside other PC apps, I can now use SkySafari to control the scope and Sharpcap to run the camera, on the same PC at the same time. 👍 Not only that, but the hand controller is still in the loop and can be used for manually nudging the scope whilst looking through the eyepiece. ....not only that, but the whole caboodle works with my Starsense autoalign for Skywatcher too, (with the SkyFi plugged into the Starsense's USB socket in the handset.) At last (famous last words - again), I can run any of my goto mounts via my Android tablet or my PC and still have the hand controller operational. I must admit, I'm really moving over to SkySafari Pro from Stellarium, the interface and display seem even nicer, and there's a lot more pro-active "suggestion" content for what to look out for at any particular night's viewing. ...and I've even now discovered that I can import my own panorama background into it too, just like Stellarium, so I can actually see when Planets are visible to my slightly obscured Southern horizon (nearby houses), when the ecliptic path is so low in the Summer.

I know the SkyFi III wifi device can connect almost any make and model of goto telescope, but how universal is it for software other than Sky Safari ? It works brilliantly with SkySafari 6 on my Andoid tablet, but I haven't managed to get it working with my PC running Stellarium. I can connect successfully via Stellarium's "direct cable connection" using the skywatcher serial cable, with a USB adapter at the PC end, and plugging the RJ12 connector into the second socket on the base of the Synscan controller. When I use the same serial lead plugged into the RS232 socket on the SkyFi III however, I can't get Stellarium to connect via wifi. I thought the SkyFi simulated a standard com port via wifi ?

...maybe that's another plus for the fibreglassing method. In effect, the original dome is just being used as a mould, so the fibreglass skin is a complete new entity in itself, not depending on the thin plywood panels for strength any more. Though the internal ribs are still essential to provide rigidity.

On my flat garage roof (as pictured in my post above), I used two layers of mat and polyester resin and then pigment gelcoat. Now that DIY kits for flat roofs have become popular, the costs of the fairly large quantity of resin and mat have become very competitive via mail order. I used these people https://www.fibreglassroofingsupplies.co.uk/category/grp-roofing-packs (I can't claim it to be a "Which" best buy recommendation, as I've only used that one company, and only once, but the service was prompt and the materials were excellent.) The kit I used for my 3 metre wide 6 metre long flat roof was: Roofing Pack - 1 x 600g + Topcoat (Premium Roofing Resin) Light Grey-20 Sq Mtr £222.50 plus vat (then) It included a hefty roll of mat and 40 litres of layup resin plus 15 litres of gelcoat ("topcoat"), so being able to buy it as a mass produced kit was so much cheaper than sourcing that quantity of materials elsewhere. As your dome naturally sheds snow and rainwater, I would think you could get away with just one layer of mat (the 600g CSM is quite thick). I also bought from them the preformed plastic edge sections that were GRP matted over to form the raised edges neatly, and I had already covered the roof with OSB sterling board T&G exterior chipboard, (as they recommended), but you won't need to do either of those with your dome. The skin this formed is amazingly impervious to weathering, and as it's really stuck to the surface, it has strengthened it as well. (as it would your segmented plywood dome, makeing it effectively one piece.)

I know you said you prefered to not use fibreglass, but if it was me, I'd certainly do it that way. As Mike said, you could do it in sections and rotate it. The beauty of fibeglass is the way it confirms neatly to that awkward convex shape, (with the segment joints). When the matting is "wetted out" with the resin it flattens against any shape, and clings to it. Fibreglass sheathing is so easy to do and makes such a permanent job, and could be quite neat too. You could mix a pigment of your choice in the layup resin so you'd never have to paint it either. (even simulated green copper !) I did my flat garage roof 10 years ago with a kit, and it's as good as the day I did it. (and that's the bare fibreglass, pigmented grey, so never needs painting.) Prior to that I'd used roofing felt twice, which was actually harder to do, and only lasted 3 or 4 years before cracking somewhere, rendering the whole thing useless.

I'm afraid it looks as though you may have blown the main motor board just like I did. It's an easy mistake to make with these Flextube Goto Dobs, because Skywatcher chose a dangerous combination of socket types on the main motor panel. In the photo attached, it shows that the Synscan handset must be plugged into the smaller RJ socket on the left, which is a 6 way RJ12. (And when using the Starsense for Skywatcher accessory, the linking cable from the Celestron Skywatcher Adapter hub must also be plugged into the smaller RJ12 socket, and not the RJ45.) The empty 8 way RJ45 socket next to it on the right, is exclusively for use with the special linking cable that goes down to the AZ motor in the base. The big danger with this is that although they are labelled, it's so easy to plug an RJ45 accessory item, (such as an EQMod adapter, or the Starsense for Skywatcher linking cable) into this linking cable socket. In my case, my RJ45 EQmod adapter immediately blew the PIC controller on the MC004 motor board inside. The mistake is made even more likely because Skywatcher often do connect their Synscan handsets to the mounts via an 8 way RJ45 socket, like on the EQ5. ....However, on their AZ mounts, like the Goto Dobs, Skywatcher connect their Synscan controllers via a 6 way RJ12 connector lead. It's such an easy mistake to make, and I'm so determined that in a possible future moment of forgetfullness I don't make the same mistake again, I'm going to make a neat little screw on clip that holds the RJ45 linking cable plug (semi) permanenty in place !

Mine too..... As John and Ade have said, you can only notice the full range of dimming over the full range of the rotary control in darkness. You'll find it's right round at the "lower" end when you're trying to centre a dim "fuzzy". In fact you can buy a very useful add-on for them that adds the ability to flash on and off at variable rates. This helps even more, allowing your eyesight to pick out very feint objects during the "dark" pulse and centre them accurately. https://www.firstlightoptics.com/finders/telrad-pulsar-reticle-module.html (shameless plug for FLO 🙂, who's price for it is very competitive, and quick delivery)

Thanks Archie, you and Malcolm have saved me a great deal of money, and even more importantly, saved me having to wait 4 months for the parts to arrive by slow balloon from China...... 🍺

Yes indeed... 🍺🍺🍺 whoopee..... The board arrived from Malcolm in today's post and after I plugged it in and tried the up/down buttons, the Alt motor whirred into life again !! I've been busy all day putting it through it's paces and it's tracking and "going too" with no problems. It displays the co-ordinates correctly when "pushed too" as well. (These goto Dobs have dual encoders). The only very slight glitch at the moment is that when the slew speed of the Alt motor is lowered below 5, it single steps in jerks, rather than smooth slow motion. When I put it in siderial tracking, both motors are "ticking" quietly so it appears that the Alt can move slowly and smoothly when under auto control. I tried "daylight" alignment on the Moon, and then it correctly slewed to Polaris and Vega as gotos. (I was able to check in daylight using the setting circles on it, as well as the handset's "show position" function. Malcolm and Archie have not only saved me a great deal of money, but the alternative cure of buying replacement parts was fraught with uncertainty due to the Skywatcher Goto Dobs having just been "upgraded", making it difficult to know whether a new replacement Alt board would work with my still functioning AZ board, (and would take 4 months to obtain from China).

Shimrod, thanks again for the heads up with the Skyportals incompatibility with skywatcher. 👍 I've now researched it on the web a lot more, and I think I understand the limitations now. The Skyportal wifi dongle can control Celestron mounts connected via the Starsense Autoalign hardware. The Starsense Autolalign hardware can control skywatcher synscan telescopes via the hub that comes with the Starsense Skywatcher version. ...However, it appears that when that SW hardware hub is used, it only works with the Starsense hand controller, and not the Skyportal wifi dongle. It appears that the SkiFi 3 wifi adapter is compatible however, because instead of plugging into the celestron skywatcher hub, it plugs into the starsense hand controller, via either a USB lead or a serial lead (depending on which version of the starsense hand controller is used). Not only that, but the SkiFi 3 seems to be quite universal, in that it can act as a wifi interface to most other manufactuer's hand controllers, with it's serial and USB interfaces. This is because nearly all of them can be controlled by hardware leads plugged into their handsets. Having a Wifi "bridge" to the mount's wired serial or USB port makes things much easier with Andoid hardware and apps too, because their USB ports usually need "OTG" adapters, which add another layer of compatibility difficulty when used with serial to USB adpters at the telescope end. ...so, I now have a SkyFi 3 on order, which I'm hoping to use with my Celestron Starsense Autoalign for Skywatcher, and run the whole shebang via SkySafari 6 on my 10 inch tablet . ...what this space.... 👀

...Seconded (by me, the OP 🤓) Excuse me if I'm repeating myself here, this is now quite a long thread and my memory is not as good as it used to be..... As Malcolm has said, if the remedy was just a case of ordering the single small PCB that is faulty, then I would have done that 3 months ago. I did buy one in fact, from a European Skywatcher main importer, but unfortunately the box contained a part that was completely different to that which it pertained to contain, so it was returned, (and promptly and apologetically refunded, no problem there.) All of the Telescope mail order companies and main agents that I have contacted have faced two major difficulties, this unprecedented world-wide Covid situation, plus the fact that the Skywatcher Goto Dob range has recently been significantly modified since mine was produced. This has resulted in much uncertaintity in which replacment parts are compatible with each other, and therefore how many parts I would need to buy, even though my problem is caused by just one small PCB. ...enter Malcolm and Archie... expending much time and effort on my behalf on a completely non-commercial basis, (he hasn't even let me pay for the return postage or the blank PIC chip yet). 🍺🍺

Good idea Padraic. I took advantage of photoshop myself with something similar when I was making a note of the voltage readings around the board. I put it in a layer and then dimmed it down to 50%, so that when I printed it my handwritten figures would show up more clearly.

Ok, here's the bigger photos of both sides of both boards. I had to take them at an angle to avoid the reflection from the ringflash. They're both almost identical, apart from the obvious missing RJ12 and power socket from the AZ "slave" board. As malcolm suspected, there's one or two small components near the PIC that maybe telling it whether it's the AZ or the Alt. Thanks Archie....

Leave that with me Archie, (something I can manage at last.. 🙂) I'll take some high res photos of both sides of both boards and post them on here, (they'll be big !)

No need for apologies Malcolm (ever 🙂) Yes, that's why Skywatcher's choice of sockets on this mount was so risky. (that's my excuse anyway !) The Synscan hand controller plugs into an EQ5 mount via an RJ45 socket, so the EQmod adapter has an RJ45 plug. On the synscan goto Dobs, the cable that links the Alt motor board to the Az motor board is the RJ45 at both ends, and the synscan hand controller plugs instead into the RJ12 on the Alt motor cover, right next to the RJ45 socket. 😬 So if you're not concentrating (like I wasn't), it's quite easy to plug the EQMod RJ45 plug into the RJ45 socket on the Dob, and boom....... resulting in a repair that will cost around £200, and a 4 month wait. It would have been much safer to have a completely different type of socket linking the two motor boards.

The handset socket is the RJ12 6p6c, the RJ45 8p8c is the linking cable to the AZ board. (or have I misunderstood what you're saying Malcolm ?) 🥴

R2 is 10.1k D3 is 700 ohms pos to pos and neg to neg and more than 2000k ohms reversed. I checked the same points on the AZ board and they were exactly the same (unfortunately).

Ok, I've now checked the things that Archie mentioned: When I power up the scope with the AZ board disconnected, it beeps and say "no connection to MC - standalone mode only" I was still able to enter "PC Direct Mode", but the programming software couldn't show the current version and the programmer couldn't reprogram to PIC. (with a "no connection" message). I then powered off and reconnected the AZ board, the programmer then verified the current version as V2.9.98, and I was able to run the program option again, which took 42 seconds to reach 100%, and then after a further 10 seconds it displayed the failed message. (so I guess it was only able to verify and program the PIC on the AZ board). I'll check D2 and R3 with the meter and then make another reply. Thanks for the suggestions, keep them coming ! (please) 🙂

Thanks for the detailed suggestions Archie. 👍 I'll check the things you mentioned and then reply again.

I'm getting really keen on SkySafari 6, (in serious danger of defecting from Stellarium 🙂). As it won't run on my PC I use it on my ten inch Andoid tablet and connect to my skywatcher synscan via wifi. I'd like to connect via direct cable though, which is a problem with the tablet, as it has no com ports and I have to use an OTG adapter to get the USB port working in host mode. That does actually work, because I can read USB memory sticks via it. When I try to use my skywatcher cable though, I have to use a serial to com adapter, and I think it's that link in the chain that is not co-operating. I know they're a bit fickle with windows anyway, demanding exactly the right drivers. With it all plugged in, the telescope setup page in SkySafari just shows Wifi and Bluetooth as the options, and no com port appears. So has anyone managed to connect an Andoid device to a scope by direct cable ?

I'll keep this thread updated as and when anything significant happens in case anyone else finds themselves in the same boat as me with one of these mounts. Plan "B" ( Malcolm's very generous work on the board together with Archie's suggestions and other member's input on here to attempt to fix the board), has not been successful, (despite extremely vailant efforts). I'm therefore still pursuing Plan "A", to obtain an official Skywatcher replacement part. Despite the 300p goto Dob being something of a premium current telescope, managing to obtain the neccessary motor control board is very difficult, due to the unprecedented difficulties faced by companies with the ongoing Covid situation and also the unfortunate fact the Skywatcher appear to be in the process of significantly altering the mechanics and electronics of these Dob Goto mounts. The actual single faulty component, ( an MC004 - Alt motor controller board ) appears to be no longer available from anywhere, and the alternative "upgraded" parts needed to replace it are proving to be very difficult to assess, let alone obtain. That board has been superseded by another with integral wifi, and it may no longer work with my existing undamaged AZ motor controller board, as that is now quite different too. To compound the problem, this mount now has new plastic covers to accomodate those new boards, and worse still, the motors inside appear to be completely different, (as the attached pictures show). Skywatcher seem to have turned them around, so that the gear and pinion and cluches are now on the outside, instead of being behind the panel, as in my original goto dob mount. This appears to be to enable them to be now adjusted externaly, via large plastic knobs. So the problem now is to try and assess how few parts I need to buy to "mix and match" with these newer components, ie whether I can just fit the newer "upgraded" Alt motor board into my housings and whether it will successfully work in concert with my existing AZ motor board. If not, the total cost of the parts will probably not be economically viable, let alone the predicted 4 month delay for them to arrive. Watch this space.......🥴

Thanks for the suggestion Padraic, but as Malcolm has said, that is the item on TS that I ordered a couple of months ago, and which turned out to be a completely different item. They paid fro the return postage and refunded me, but haven't been able to help me any further with obtaining the correct board. I noticed myself a couple of weeks ago that they were still showing that page with exactly the right item that I wanted, and that it was in stock (raising my hopes !), so I contacted them about it. Unfortunately their reply was that they still couldn't get the right item and that they would update the page. As it's still not been corrected it would be unfortunate if another customer ordered it like me and had to return it.....

Well it was a Valiant effort from Archie and Malcolm, and Malcolm got the repaired board back to me in superquick time and did a very neat job with the tiny components. ...but I'm afraid the fault persists, with all of the symptoms exactly the same as before, namely: It powers up the handset and runs the AZ axis (left/right buttons) perfectly, responding to speed changes etc.. The moment the Alt axis buttons are pressed (up/down) there is no response and the hand controller then freezes until it is switched off and on again. When I switch the boards over, (connecting the Alt board to the AZ motor and the AZ board to the Alt motor), then the opposite occurs, ie the Alt axis moves perfectly, albeit via the left/right buttons, and then when the up/down buttons are pressed, the AZ axis freezes the controller without moving. I think that proves there's nothing wrong with the motors and encoders, or the AZ board, (which was unplugged anyway, when I blew the Alt board). I've also ruled out the handset and cable too, because I have identical ones with an old AZ goto mount and they work with that, and the HC and cable from that doesn't work with this board. I guess the power must be ok too, as it runs both motors individually and the handset with no problems. The only other quirk with my testing is that these results are all with v.03.08 firmware on the handset. When I tried v03.39.05 on the handset, I could get no response from either motor, because the handset simply said "no connection with MC". Presumably this was because the newer HC firmware does more HW checks when starting up. I've now heard from the main distributor, it sounds as though the pre-upgrade boards are still available as replacements, but there is a 4 month wait for them. As I've said though, I'm most grateful for the time and effort from Archie and Malcolm and the other replies I've had on this thread. 🍺🍺🍺

Thanks Shimrod, I'll set up a login with them so I can read it. Funny thing though, Celestron's own page currently advertising SkyPortal has a selection of linked products at the bottom that they say are "Compatible with SkyPortal", and in amongst them is the Starsense AutoAlign for Skywatcher. They must get quite a few disgruntled returns if it still isn't compatible. The other thing that intrigues me on that page is that the Starsense Autoalign for Celestron has an RRP of £359, and yet the Skywatcher version has the same RRP and is even reduced ( £359 down to £299), and yet surely they're exactly the same, but with the cheaper Skywatcher version also including the SW connecting Hub..... 🤔 https://www.celestron.co.uk/technologies/celestron-sky-portal/

Sorry Victor, I've never tried writing scripts or used Linux. The Synscan app Ascom driver does work with all my other Ascom software though, sharpcap etc., slewing the mount successfully, changing the speed etc..