Motherboard Chips Needed

[PadrePeace]

I have a guy working on a faulty mount motherboard for me and I have the job of sourcing the chips he needs.  Most online suppliers have a 'min quantity available' limit and sell items in 50 plus bags and are asking £15 for the single 0.03p chip needed once handling and shipping (often from the USA) is added.  Those that don't are charging 1000% markup.  I even spoke to RS Components in the UK and made a plea for just one of each - no joy there.

So, I guessing this wont be surprise to some of you and this is what drives our throw away society I guess.

Has anyone out there got any of the following laying around and would be prepared to sell one of each? 

Diodes Inc, 3.3 V Linear Voltage Regulator, 1A, 1-Channel 3+Tab-Pin, SOT-223 AP1117E33G-13
Diodes Inc, 5 V Linear Voltage Regulator, 1A, 1-Channel 3+Tab-Pin, SOT-223 AP1117E50G-13
Microchip MIC2171WU-TR PWM Switching Regulator, 2.5 A, 115 kHz, Adjustable, 65 V, 5-Pin, TO-263
 

many thanks for looking............

[MarkAR]

Mouser.

https://www.mouser.co.uk/ProductDetail/Diodes-Incorporated/AP1117E33G-13?qs=%2Fha2pyFadui%2BwK%2Bbolu%2BjYEdBZN5gMtDM87bym%2Bj6Xg0n%2F6jTSwC%2FkcacqYqixwy

https://www.mouser.co.uk/ProductDetail/Diodes-Incorporated/AP1117E50G-13?qs=%2Fha2pyFadui%2BwK%2Bbolu%2BjRaMjy%2FvDIsbbbfYpH6yc6N80aJ%2B3%2BftQER3w%2BBU0Oxd

https://www.mouser.co.uk/ProductDetail/Microchip-Technology-Micrel/MIC2171WU-TR?qs=%2Fha2pyFaduikL6rSCjEMYQ5%2FCd7LXze2KxKZ6Ve%2FoeO3wou40d1HPw%3D%3D

Hope they are the right ones, just copied and pasted codes into their search.

[PadrePeace]

Thanks MarkAR appreciated. I had found those guys, called them only to find their Agent office in London is only that, all stock is in the USA. They ship from the USA through FedEx at £15 a shot and then the Royal Mail have an £8 UK side handling charge so it all gets rather silly for chips costing less than £2. Also contacted RC Components UK and Farnel and it get expensive fast when your trying to track down a failure. 

I  was thinking more of guys on this net that may have gone down this route before and have some stuff left over. 

[MarkAR]

That sounds like Mouser being daft.

All three items show as being in stock, how can a UK based company say it's in stock if the actual stock is in the USA. Unbelievable.

Basket comes to £4.29 + £12 Delivery, quite often for small items the post do not collect a fee. Had my Optolong L-Pro just dropped through the letterbox from China, no extra fee paid.

[MarkAR]

Two out of three available in the UK on Ebay, the other from China, Total will be about the same as ordering from Mouser.

[JemC]

I have no idea about any of this, to technical for me 😀

just out of curiosity, would these be on any motherboard or only certain ones? reason i ask is i have an old HEQ5 Motherboard that i am about to throw,

[Carbon Brush]

Don't shoot the messenger.

I'm not really surprised by the issues you are having.
For quite a few years there has been the ever expanding range of components, coupled with the trend to surface mount packages that discourages hobby building, coupled with people's general lack of interest in understanding circuits to component level. There is therefore no real support for the (few remaining) hobby builders.

The biggest surprise is you finding someone who is prepared to get stuck in and attempt a repair.

However, on the shopping basket cost with delivery, etc. It is only a main course meal at the pub - if you could get one.
Most garages charge much more than this to pull the code reader out of the cupboard. It is a tiny tiny fraction of the cost of a half decent scope.
The component suppliers are mostly geared up to serving the manufacturing sector. Not the one off repair sector.

The linear regulators are nothing special, so you should be able to substitute devices from other manufacturers.
I'm not familiar with the switcher regulator so won't comment on choices there.

I would though urge caution before going further. If you have had an 'event' that has taken out all of the power supply chips, I would not put money on much else surviving.
For example if a microprocessor has failed, you can buy another. But do you have the programme to put into it? Do you have a programmer?
Sorry but I think you either have a true 'write off'. Or the diagnosis of 3 voltage regulators failed is wrong.

Don't shoot the messenger,

David.

[Carbon Brush]

It is probably a good idea, before suggesting solutions, that the thread below be read.

 

[malc-c]

To be honest, having to place £10 and £15 orders here and there for part, plus you have no idea yet what the final bill would be from your tech, I would bite the bullet and buy a replacement for £159

https://www.rothervalleyoptics.co.uk/skywatcher-replacement-motherboard-for-az-eq6-gt-mount.html

https://www.microglobe.co.uk/sky-watcher-motherboard-az-eq6-gt-with-usb-p-20187.html?

Not sure about modern board, but Synta were always criticized for not providing adequate protection on their boards for reverse polarity.  It may well be that other components have been affected and you could be constantly chasing your tail in order to resolve the issue.

Edited April 6, 2020 by malc-c

[Dr_Ju_ju]

I've had to make 2 repairs to an AZ-EQ6 motherboard, one was my own fault, when I was giving it a service & knocked off a surface socket, the 2nd was when a small spider got into the ST4 port, that has the regulated volts on it, it built a small web, which got wet with dew & blew the on-board regulator.  Since then I keep an 'empty' plug in the socket....

For me, both were easy to source parts, fix & replace, but then I have very long standing accounts with Farnell & RS Components, and the appropriate tools & skills.... 

[PadrePeace]

All

Thanks for the continued inputs on this thread. The board is on its way back from my tech who had a picture of the hand controller reading 'EQ Mode' which is the first thing you see when you switch the mount on. If it is fixed I'll back brief you all on 'what and how' along with a 'who' if any of you should need to go down this route.

[PadrePeace]

As a final update, for anyone following this thread I am pleased to report that the board has been fixed and is now fully functioning. This required the replacement of the switching regulator and the two voltage regulators highlighted in the picture below. Big thanks to all of those who shared their advice and experience and helped me get this board back up and running.

The biggest thanks go to Rob Miller (FB linked below) who helped diagnose the issues and toiled over a hot soldering iron to bring this motherboard back to life. He carries out this kind of work for the Astro community as a hobby and will only charge his time if he fixes the item. That’s hard to beat. 

https://m.facebook.com/groups/1849691625242921?view=permalink&id=2575157922696284

Hopefully this thread will help someone else down the line. 

1. Diodes Inc, 3.3 V Linear Voltage Regulator, 1A, 1-Channel 3+Tab-Pin, SOT-223 AP1117E33G-13

2. Diodes Inc, 5 V Linear Voltage Regulator, 1A, 1-Channel 3+Tab-Pin, SOT-223 AP1117E50G-13

3. Microchip MIC2171WU-TR PWM Switching Regulator, 2.5 A, 115 kHz, Adjustable, 65 V, 5-Pin, TO-263

Clear skies to you all.

Edited May 22, 2020 by PadrePeace

[malc-c]

That's pleasing to hear.  For the benefit of anyone else requiring a repair could you advise of the costs involved (ballpark figure would do, no need for a breakdown of costs) just to allow them to compare the cost of repair against replacement.  

I love the way this community comes together to help fix these mounts in this throw away world we live in.  

[PadrePeace]

Cost would be best assessed by anyone who wishes to know Googling the parts and seeing what comes up for them. I only say this as they can vary both in cost and availability which is why this has taken so long to sort out.

Suffice to say it was sufficiently cheaper to fix than to buy a new one. Also note that some popular retailers don’t do the old non-USB board anymore and were only selling the new MB without the metal face plate (despite picturing the metal plate in their add) which is an additional cost if they can order one in. Each must look at this set in their own context as the variables are many and we all have a different appetite for theses kind of things I guess. 

[malc-c]

Granted it would be much cheaper, but for anyone contemplating this might be put off by spending £30 on diodes, only to have 98 of them left over.  Plus his facebook page gives the impression this service  is run as a business, so could be charging more than the 32p each diode costs.   I appreciate it's a personal transaction, hence the statement of a ballpark figure, but respect that it may be something you don't want to disclose.

I agree with your comments about the older boards being hard to source.  I'm involved in trying to fix a board for a Dob, which uses two identical boards, and the owner has found it impossible to get a decisive answer as to the compatibility between older boards and the new one with wi-fi for the reasons you mention... It's really disappointing to see manufactures no longer providing spares for their products that are less than two year old.

Anyway, glad to hear your board is fixed and its given your scope another lease of life

[PadrePeace]

If it helps anyone Rob does this in his spare time as a hobby along side his own astronomy. He can get the parts or will be happy for you to do that and will always discuss those costs with his customer first before any cash is spent. He makes no profit from the parts. He pays what you pay. In my case I decided to source the parts myself as he had lots of other draws on his time at that point and I wanted to move the process on as quickly as possible. 
His hour rates are better than fair and I’d go as far as to say surprising. If my board had not been fixed I’d have owed him his postal costs only.  
If anyone wishes to know how he operates they only have to contact him. He’s a true gentlemen so please don’t get the wrong impression from his FB page. He’s one of us and happy to help fellow gazers when things go wrong because he has the skills and believes it’s the right thing to do. 

As a final thought, if anyone is ripping off customers its the chip suppliers who will not split their minimum retail packs up and over charge on post and ‘handling’ charges (whatever that markup is for).  So chips do actually cost pence but you cannot get them individually. This is why not many bother with repair these days. It’s such a perverse thing that we trash our gear for the sake of guys like Rob and a small chip (or ten).

just saying.....

Edited May 22, 2020 by PadrePeace

[Adam J]

Yes as you say chucking out a perfectly good MB for the sake of a couple of components is part of whats wrong with the world these day. Glad you got it fixed and i will be using this chap in the future if I have problems.