malc-c

It does look as if the driver chip has had a melt down of sorts. Ed, if it proves that the return to life is temporary then drop me a PM and I'll replace it with one from one of the dead boards that has been sent to me which turned out to be beyond repair. These boards have very little surge or over voltage protection, often relying on a diode to act as a fuse, which results in a completely dead board. Other issues is damaging one or both PIC micros by placing 12v on the communication lines when using the wrong EQDIR type lead or USB convertor.

I've always used fablon that has a material texture as it does a better job of absorbing stray light than a hard surface. Fablon is also a lot cheaper - £200 for a litre of paint

Shuan, How old is the mount? - I've repaired several HEQ5, EQ6 and boards from dobsonian mounts, but I'm limited to the older generation boards when it comes to replacing the main processors. However most blown boards that occur through power supply issues such as wrong polarity tend to be a reasonable easy fix as they often (not always) are a protection diode that blows as a sacrificial "fuse" I'm willing to take a look at it for you, or if you do go and get a replacement form Firtslight Optics or Rother Valley Optics then please drop me a PM and donate the board to the exchange program. I set this up so that (where possible) boards can be recycled and if I can effect a fix then they can be offered to any other SGL member who needs a replacement board for just the cost of the parts and a drink to cover my time and postage. But to make it work I need people to donate their faulty boards to get the ball rolling. Let me know what you decide to do Regards

Regardless of the type and cross section of the pier, it seems we all then use three M10 / M12 bolts or threaded rod with washers and nuts to secure a plate carrying the mount. Doesn't this make the the thickness or design of the pier less important, especially as that second plate is often placed high enough to allow the fitting of the central bolt to secure the mount to it. Granted the options are limited, either using a hole cut out of a length of pipe or box section or two plates, but I sometimes feel the size of bolt is often overlooked and the choice of bolt and its length makes the over engineered base a bit pointless?

Excellent explanation David - and even learnt something, wasn't aware the numbering related to diameter and thickness - thought it was more to do with capacity or other characteristics such as tagged, PCB pin arrangement etc. I guess it boils down to Geoff's confidence to remove the hood and extract the battery and then swap the leads over to a new replacement which can easily be obtained

RS, digikey, all supply to the public. The battery can also be found on e-bay CR2430 is not a rare battery.

I'm wondering if the original concept was that AP never envisaged the device lasting longer than the life of the battery, otherwise they would have designed it so the 3v cell could be replaced. I guess the options are source a battery from the UK and follow the guide above to replace the existing battery yourself source the battery and obtain a quote from FLO / RVO or an electronics repair company to have them replace the battery for you spend a small fortune to return the item to an authorized AP agent in the EU that's willing to do the paperwork involved spend even more and return it to the manufacture in the states.

If I've followed this thread, the 3v battery is used to keep the memory (or clock chip if one is used) alive rather than use flash memory that doesn't need power. It's a 3v battery, and as such provided you maintain the polarity replacing it won't do any damage to the high end device. I would assume AP has a UK agent / distributor, and you purchased the device through a UK retailer ? - if so then I would have thought that the retailer or the likes of FLO or RVO would be able replace the battery for you.

2430 Tagged - £3.10 each Should be easy enough to follow the instructions linked to above and solder the wires to the tags

If the 2430 is thicker then a thinner 2032 will fit. It only becomes a problem if it was the other way around

I agree with the post above, invest in a powerbank and suitable lead. With a 10 a/h capacity that would keep you going for the night and is much safer than running mains outside to use a suitable wall block power adapter

Just took a look at the instructions linked to in a post above, so its a PCB mounted battery, This 2032 has a 1ah capacity and appears to have tags in the same position £3.37 inc VAT form Farnells (plus delivery)

If the battery required is the same as that shown in Geoffs post above you can get replacements in the UK. Most component supplier such as RS, Farnells or Mouser stock them, including ones with tags that can be soldered direct to a PCB. If you are not bothered about the capacity (the 2430 is a 300mA battery) I have 2032 batteries (225mA), with the same plug sitting in my components draw. If replacing the battery is a simple task (such as undo screws, remove case, detach battery, plug in replacement and screw the cover back on) then drop me a PM with your address and I'll send you one.

There used to be some "rule" where the norm was to make the pier base from a cubic meter of concrete, but as shown above, 600mm cubed seems adequate. When considering options when I was designing my observatory I looked at commercial offerings and to me they seemed overpriced for what they were. In the end I opted for the traditional 6" drainage pipe, sunk into a big hole in the ground filled with concrete. The tube was stuffed with rebar and filled with concrete, with the 12" rods from the base of the mounting plate for the HEQ5 sunk into that. This then supported the EQ5 until I picked up the HEQ5 the following year The mounting plate was made by a local company for a drink, but shouldn't cost more than £50 to have it turned, drilled and anodized. I think at the time I saved myself about £300 compared to buying a fabricated pier made from steel.

I was bored this afternoon, so I programmed a couple of 16F886 PIC micros with the firmware for a SW goto mount and placed them on a solderless breadboard. The Links were made and diodes added exactly as found on SW motor board that used these devices. Using an FTDI USB to serial module power was supplied and the TX/RX lines connected by jumper wires to the TX/RX pins of the PICs. Plugged the USB cable in and device manager reported COM6, and set this up for 9600 baud. Opening up a serial terminal and selecting Com 6 I could send :e1 to the two PICs and got the 0204 response confirming the PICs are working and the version of firmware was reported back. I could even open a test application which interrogated the PICs further and all reported fine ( the PC was talking to an EQ6 !!) I then programmed a 16F1455 with code that basically makes this PIC a USB to TTL serial device the same as the FTDI chip. Bread boarded this chip, and performed an initial test of linking the RX/RX pins together and then opening a second terminal window and setting that to Com 7 I could get back any text string, confirming it was working. To prove this one step further I connected the TX from the FTDI module to RX of the 16F1455 and the RX from the FTDI to the TX of the 16F1455. Now whatever text I send from the terminal window for com 6 was received by the terminal window of Com 7, and vice versa. So I had established two way communications at 9600 baud. So the TX and RX connections from the FTDI was removed from the 16F1455 and the 16F1455 was connected to the 16F886's, but no matter which way round I have the link wires, sending e:1 to the "mount" doesn't return the firmware version. Which is strange as I know the "mount" is working as it responds OK when using the FTDI module, and I know the 16F1455 is working as it was talking fine to the FTDI module... But the 16F1455 just won't talk to the "mount" Maybe this might explain why some people get issues with EQDIR cables that are not based on FTDI devices.. I even hooked up the 16F1455 to a DCC train controller that used serial in and out, and it talked fine to that and even updated the firmware via the PC application, confirming that the 16F1455 code works as expected. So we have two USB to TTL serial devices, both work perfectly well yet when connected to a SW "mount" only the FTDI device can communicate with it. I'll continue to mess about with this for fun as it would be cool to get it to work with the 16F1455, but hopefully goes to show why we are always recommending FTDL based EQDIR cables for use with PC control of a SW mount.

Not 100% sure about compatibility with modern versions of software, but back in the day there was an issue with compatibility with SharpCap, which would only work with a WDM (?? or something like that) driver, which whilst it gave a picture, a lot of the functionality found in the QVideo application for camera control missing. This may now have been redressed, but given the age of the camera it might be unsupported by some modern applications. I second that... works great with PHD2 through both an ST80 guidescope or a 9 x 50 finder converted.

Late to the party... but yes that's a QHY5 - Driver and application attached QHY5.zip

In an earlier post you needed help on identifying the positive wire from the power jack. Red typically indicates the positive supply, so if you had used red heat shrink it could help you at a later date or as has been mentioned if the mount is sold and the next owner needs to service the mount. Thick wires... have more mass and thus put more strain on the thin copper pads, which on these boards is just 34um (or just 0.0034 cm) thick. Thick wires also have a larger area in contact with the copper pads so it's more prone to being lifted, and is the reason designers fit sockets or header pins as the terminals are soldered through the board, thus providing a mechanical means of support. I've not looked back through the thread to see why those wires are so thick, but seeing that at most the mount draws about 2 to 3 Amps there is no need for that gauge of wire to be used. 16/02 (sixteen strands of 0.2mm twisted) is rated at 3 amps ( often stated at a 1000v, which is irrelevant as 3 amps is 3 amps at any voltage) and has an outer diameter of 1.6mm including the outer PVC covering.

Stuart... these were my thoughts too... Our advice has been ignored and it will only be a matter of time before some fault will arise. Given the discussion on polarity of the wires he's used black heatshrink on BOTH wires. I bet heatshrink manufactures wonder why they bother making heat shrink in a selection of colours including red ! I have at least three EQ6 boards that I have fixed and are awaiting swapping out under the "exchange program" set up to help other SGL members... but I would be reluctant to offer one when the OP has messed about with it in this way.

Julian, from my experience the only protection against reverse polarity on SW boards is a small diode or more often an ceramic bead inductor which act as a sacrificial "fuse". Even a basic bridge rectifier could have been added to insure the rest of the board doesn't receive inverse voltages or AC should the wrong adapter be used. Most of the time SW are relying on the user using the correct centre positive barrel jack power supply.

I think it's knowing personal limits and when you get out of your depth (some people should never enter the water !) - Being trained to solder to ministry of defense standards at what was British Aerospace I'm comfortable at working down to SOIC level on PCBs. But even if I had the tools I still wouldn't entertain re-balling a GPU , at least not after a lot of practice. Seeing thick heavy gauge wires, poorly tinned and then dry jointed to the thin copper pads is so upsetting

As mentioned you clearly have very little understanding about electronics and the way electricity works. Most people might be able to change the spark plugs on their car, but certainly lack the knowledge, skills and tools to mess about with the internals of the engine, and the electronics in a modern mount is no different. It doesn't matter if you have an 8A rated cable or a 30A rated cable, it would ONLY be an issue if the cable was rated at half an amp, i.e. a lot less than the 2A a mount typically draws when slewing (although the initial current surge that happens when the steppers start is more, which is why people will recommend a 5A rated supply. The cable rating is not how much is fed to the mount, it's how much constant current it can handle flowing through it. I have to agree... and like other cringe reading the OP's posts,. It's bad enough when someone accidentally blows a board, but when they hack about blindly not knowing the basics, even after being advised not to, then I have no sympathy when it all goes tits up.

I have to agree with the comments above. If you have no understanding of electronics or how to test a barrel jack to see which terminal is positive or negative then you shouldn't be doing this. I was quite taken aback by the statement that if you fried the board so be it, you can always get another... Last time I looked EQ6 boards were £150 a pop... If you have a connector that you need to work out the polarity the normal practice is to set the multimeter to DC volts, shove one probe into the barrel of the plug and the other to the side. If the reading is negative swap the probes around so the red one is inside the barrel to confirm. Having identified the positive connection (which in this case is the centre pin of the barrel connector) the other terminals will be 0v (or GND). Soldering is a skill that some can master to the point of reballing the processors on modern graphics cards with the right tools. IF you still want to risk damage to your board then practice the basics which include stripping, tinning and soldering wires. The wires should also be short, so that the solder joint is no larger than the pad you are soldering to, with the insulation as close to the pad as possible to avoid contact with other wires or components. There was mention about "ground planes" - don't assume a solid area on a PCB is a ground plane. Some multi-layer boards (these boards are 4 layers) use them for various reasons not always as a ground plane for the power circuit. I still feel removing the barrel jack and the header plug and soldering the wires directly gains nothing in this instance. In fact for the reasons I've already stated, over time more damage can be done

That's an accident waiting to happen. The reason manufactures use connectors are more than just the convenience of easily connectivity. They take most of the support of the weight or movement of the wires. Soldering direct means that the weight or the harness and any flexing of the cables is relying entirely on the solder joint. If the joint is sound then given time the wires will brake, or will lift the tracks as suggested. I have to agree with the other comments... Working on electronic takes a certain level of expertise and to be blunt whilst you have enthusiasm you lack the skills. You can have all the tools, but unless you know how to use them it's pointless. One other thing to take on board, these motor boards lack protection circuitry. Apply 12v to the wrong connection and it's good night for the board - Over the past two-three years I've repaired dozens of PIC16F886 based control boards which have been damaged simply by plugging the wrong connector in to the wrong port. Sorry if I seem blunt, but on this occasion it's so you don't end up frying the board and then need a replacement.

The MK20DX256 is the main ARM cortex processor, so you would need to find the firmware file, convert it to HEX and then use a programmer to upload the HEX to the replacement processor. The fact you are still having the same issue with the replacement board suggest that something in the handset or any daughter board has also suffered damage as the handset can't get a response when it interrogates the mount to obtain the mount details such as gearing etc.