malc-c

Well I thought that I would conclude this thread with a couple more images... Sadly, due to a change in my personal life, and our fixed rate mortgage deal coming to an end in July I am having to sell up and move home. Having cleared our local ASDA out of their 32litre under bed storage boxes I've been systematically packing away my electronics, model railway stock, books, etc, and today it was time to decommission the telescope. It took a good hour to pull all the cables and adaptors back through the ducting, coil them up and stow them neatly in the tub. All that's left is to de-mount the scope and pier adaptor on the day of the move As for the observatory, well the warm room that became a workshop still has a little leak in the roof which needs repair, but that will be down to the new owners. They then have the choice to either remove the wheels and fix the roof permanently in place, rebuild the roof completely, or take the whole thing apart and scrap it... would love to be around when they try and remove the pier, which is 6' of pipe filled with rebar and concrete, itself in a 1cu metre block of re-enforced concrete.... Not sure of the scopes future... I was going to sell it (even listed it on here, but had no interest) but then seeing the prices of everything I'll probably end up keeping it and either look at sinking a new pipe in the ground at the new house, or look at a smaller MKII version of the observatory if funds and space permits. It also depends on where I actually end up and how dark the skies are. It doesn't get used much these days. Prolapsed discs and damage to the Femoral nerve means the roof is a lot harder to open and close these days. Last time I had to rest up for a week after causing it to flare up trying to close it after a short session. Any future observatory will have to be a lot smaller and lighter.

Google "Bar wing bolt" You may not get something exact, but find something that will work as an alternative

Not sure about other countries, but following on form Geoff's post, in the UK the Earth bonding is (should) be connected to ground either via the outer metal shielding of the supply cable, or via a dedicated grounding rod hammered into the ground with an Earth wire run form it to the consumer unit. Then all copper pipe work is then bonded to the Earthing point

Well looking at the graph, and the resulting stack you're doing fine. Inverting and selecting a crop of the full size image the stars are reasonably round given the mount. There is signs of vignetting, and either the stacking process or that focusing could have been tweaked a little tighter as the stars have a soft edge, but the resulting image is better than some of my first attempts. The dark art of processing is another topic, so it may be worth starting a new thread on how to improve the image results, but at least now you've got the basics for guiding sorted. Polar alignment can be critical to make guiding work as it reduces the workload PHD2 will have to do, so take time to get polar alignment as precise as possible, and run PHD's calibration and tuning options to get the tracking errors as small as possible before you then consider running the imaging plan. Take your time, there is no need to rush.

Not bat at all. Did you add any darks when processing ?

IMO no. The idea is to have stable air to get the clearest views that the precision optics, be that a mirror or lens used in the scopes construction so it can produce clarity and details. The only way to do that is to place the scope outside otherwise the reflections and imperfections in the glass used in the window will spoil the results

The synscan unit in the image is one of the newer boards that use an ARM processor. It's strange that such a new board has dry and cracked joints, but glad you have manged to do some testing and found that both motors are fine and that you have found the possible cause.

I'm sure the steppers used are NIMA 17's but you would need to get one that has the same dimensions and micro stepping specifications. I would suggest you contact the retailer from where the mount was purchased and ask if a replacement could be obtained. However I would suggest you confirm the issue is the motor and not the synscan controller by swapping the motors as advised in posts above

You can control the mount using an EQDIR cable (around £40) and a PC running free software, or as mentioned a Wi-fi dongle and an app on a mobile phone. There was also some dabbling with Bluetooth to do the same as the EQDIR cable but that seems to be more of a DIY venture rather than a commercial offering

As Geoff mentions, the LCD is connected to the handsets PCB via a short flex film strip. You could try and reseat this in its connector by releasing the pressure clip of the connector where the film enters the connector, which should then allow the film to be eased out. Clean the end using some 99% IPA and reinsert the film and push the clip back home. If this fails to work then regretfully there isn't much that can be done as Synta don't offer replacement parts at component level, and whilst the LCD may well be a 2 line 16 character display, its unique to these handsets. The only resolution is to purchase a replacement handset.

Hi Archie, I think part of the problem is most forums seem to have policies that remove links to other forums and discussion groups. SGL seem to be more understanding, but yes I think we need to get the word out there that motor board can be fixed, and sometimes by replacing a cheap transistor. Reverse engineering boards is quite a challenge, especially when you only have photos to go by, so if anyone has already ordered a replacement and still has the faulty ARM based board that they can donate to the cause I'm sure it will be a great help. I'm guessing that these new boards are multi-layer, so if anyone has access to a new board and a means of having it X-rayed that really would be the icing on the cake 🙂 I know Australia is a huge place, but maybe TrevaP could loan his board to you so you get a hands on and tweak the schematic if needed.

Excellent news, well done. Now the conspiracy theorists would say that the manufactures of the board knows that a $2 MOSFET is its built in weakness in order to generate sales of replacements costing hundreds of pounds / dollars as a result of Q3 failing / blowing.

care to divulge what resolved the issue..... just in case others have the same issue...

Just googled "PHD2 and ASI Studio" to throw up similar threads - on Cloudy Nights one member with the same issue as reported here was advised to go to the camera's manufactures forum, which he did and got the following reply Prior to this there was suggestions to ensure the latest drivers and Ascom platform was installed. people reported that their cameras also worked fine in Nina, but that was down to Nina and asi studio using the native driver where as Phd2 uses the ascom driver for cameras. Hopefully the admin won't mind if I link to the post on a competitors forum 😉 Read in full here

Save me trawling through the three pages, how are you connecting the camera? - In the screen grabs it shows "on camera" selected, are you using an ST4 cable between the camera and the mount ? - Most of us tend to plug the guide camera directly into the PC via USB and select it from the list of camera options found in PHD2's connect equipment screen. To me it seems having the ASi software running takes back control after the first time PHD manages to establish communications. Testing in bright light is probably the cause of the over exposed camera image in PHD. The exposure must be shorter and you can adjust the slider to reduce the gamma (brightness) of the screen.

I also recommend leaving a gap between the observatory and the two fences to aid maintenance. Plus you may find the mini digger is not able to get close enough to be able to dig a straight trench for the foundations (assuming this is going to be a slab or dwarf wall base).

As most tend to follow the same paths this would suggest they are aircraft. Especially given how close you are to a major airport

Now I can see why the wrong cable got shoved in the wrong hole 🙂

Made a slight difference

My 200P is now effectively a PDS as I replaced the original secondary with a 1/10th wave length Orion Optics secondary the same size as the secondary in a PDS. Other mods include flocking the inside of the tube and I use a Baadder coma corrector. Camera is a modified D400 canon dSLR. Full details of mount etc in my signature

No expert, I was just lucky that replacing the two electrolytic caps worked for me. Other issues have been where the boards power up but there are no communications between handset and mainboard, which are cured by reprogramming two new PICs and swapping them for the originals. You could try removing D1 and then see if the short goes away. The other possibility is the main regulator 2171WU (marked U4). This is responsible for providing the 30+v DC to the stepper drivers. The 7805 mentioned above does indeed provide the 5v TTL voltage. The rest of the 5v line is made up of a couple of filters, and the aforementioned 470uf caps. The Schottky diode D1 is between these two filter circuits. If you get 5vdc on the output of the 7805 (pin 3) then the Diode is good. Detecting shorts often needs a thermal camera, or flux resin, or finger test to see what's getting hot. Sometimes it can be as simple as a small surface mount cap that is shorting to ground.

Not advising you to try this, but I used to get a tingle in my fingers, mainly in the quicks of the nails, especially if I had bitten them (bad habit I know) anytime I had to do maintenance in my old salt water aquarium. I was told to use a multi-meter, set to AC and place one probe in the tank and the other to an earthing point. On doing so it registered around 60v AC ! - It was then a case of powering everything off, then back on one item at a time until the voltage was detected. Turned out to be a cheap pump on the skimmer which was supposedly double insulated and thus no earth. Getting back on topic, I can't speak for EQ8 / EQ6 mounts, but on my HEQ5 the two holes that are used to secure the board to the mount have a plastic insert with a lip that isolates the board from the mount, but then the actual power input is housed separately in a plastic housing, unlike the EQ6 which seems to have it all mounted to a metal plate. With regards to the 13.8v mentioned above, my HEQ5 ran fine on a regulated bench PSU that provided 13.8v DC so I would presume that both the EQ6 and EQ8 will also be OK when run at this voltage. I also agree with comments about Meanwell power units... if you buy genuine PSUs direct from Meanwell, or through authorised outlets such as RS / Digikey etc then they last and are of a high standard. I used a constant voltage (48v 350w) supply to run my DIY aquarium LED lights. These were on 10 hours a day, 365 days a year, for over a decade and the PSU is still as sound as it was the day I got it.

Sorry have to correct you there... You can still have the 33v supply to the motors and the board will still give you the same "no axis" message. The message basically means (as described above) that the handset hasn't received an acknowledgment back from its request to the control board in the mount. The communication protocol is serial, or more correctly TTL serial where the signals levels are 5v. On older synscan mounts that lack a USB-B port, the Tx and Rx lines went directly into the PIC microcontrollers, and as can be seen in the repair thread linked above, placing the incorrect lead into the handset port blows the serial port on the PICs as they can't take 12v. The same can happen on the newer ARM based boards as the handset communications also communicate straight to the serial port on the chip. Power issues will cause the same response as the microcontrollers, be that PIC or ARM devices need to be powered and running, and if the 3.3v or 5v rail on the board isn't there due to a blown component (Q3 seems to be failing on newer boards) in the power supply section of the sysnscan board that provides the 5v and / or 3.3v rails then the board will not be running and the error message will be presented. A lot of people use 13.8v bench PSUs in observatory setups. If your car battery is putting out around 13v under load then that could rule out the battery being the problem, if it's below 12v, even by a few tenths, it could prevent the board form running. I agree that checking the power supply as suggested would be the first thing to do to rule it out. But if you get the same issue after testing with a decent 12v 60w supply that can provide the current as per the specs then contact the retailer and request a warranty replacement.

It's hard to advise as we probably have very different consumer laws here in the UK, which basically means the normal 12 month warranty is not something a retailer can hide behind if something goes faulty in month 13. It basically means that you would expect an item to last for a reasonable amount of time based on the value, which for an EQ6 is certainly more than a year. What happens when the mount is powered up is the handset sends out a request to interrogate the mount it is connected to, by asking for the mount firmware version. With the older PIC microcontroller based boards there was one controller for each axis, so if one failed to respond you would get "No response DEC axis" for example. On newer boards that use the ARM processors the message is typically both axis as the processor failed to respond. Now with the newer boards (that have built in USB ports) a FET (Q3) appears to be a weak spot, which appears to be related to the power distribution on the board, so if the processor isn't running you would get the same response. As the mount is just over a year old I would contact the retailer and ask what the procedure is to return the mount (or just the board and handset if that keeps shipping cost down) for repair or replacement. One other area is to look at the power setup. Possibly disconnect the charger whilst the mount is running. A battery charger is different form a mains power supply adapter, and it could have had some part in this.

Hard to comment as "springyness" is such a technical term that's hard to quantify. If you mean if you lock both clutches there is play in one or both axis then that sounds more like too much backlash in the worm, which you can adjust out. On the other hand you are referring to movement or flexure in the tripod the there is little you can do other then replace the tripod, which I don't recall being an option on that mount. If you can upload a video to youtube and then link to it demonstrating the issue as requested above that would be great