period jobs?

[Flyfisher]

My little bird was painted on glass and fired. Just taken it out of the kiln. Same technology as used in Medieval times except my kiln is electric.

Funny you should say that Biff; MdBs creative skills (i.e. software, assuming that big chip is programmable) will end up in a piece of fired silicon as well. Amazing what a few hundred years of technical progress can yield.

 

[robgil]

ive just made a 5 month old baby with teething pains go to sleep.
ive got 5 mins to my self now.

 

[MdB]

The chip is an FPGA which means it is programmable hardware. This is different from a normal processor that has fixed hardware and runs software. With an FPGA you program the hardware and it generally doesn't require software. However, if you program the hardware to be a processor then you also need software to program this programmable hardware.

Unfortunately, the software that runs the hardware I use to program the programmable hardware doesn't work on the operating system I'm using to write the software which programs the programmable hardware. I'm currently waiting for delivery for new hardware to program my programmable hardware so I can find out whether or not I can actually program my FPGA. Following me?

(oh and the FPGA has 144 pins, each of which is 0.3mm wide with a 0.2mm gap between it and the next pin. Quite fun to hand solder.)

Far more interestingly, I've just completed a couple more doors. They need be coated with linseed but are otherwise finished.

 

[Penners]

Mrs P always refers to my workshop as the place where I make things.

"Yesterday he made a noise, Today he's making a mess."

It was mildly amusing the first time..... :roll:

 

[Lime]

(oh and the FPGA has 144 pins, each of which is 0.3mm wide with a 0.2mm gap between it and the next pin. Quite fun to hand solder.)

I have recently had cause to replace some capacitors on my motherboard... and expect to have to replace some more.
The board dates from the 2005 Elizabethan period.
What type of solder would you use to solder the capacitors back in so that the solder flows into the holes?
My first attempts do not look good as the solder refused to enter the holes.
(If you don't mind me asking. )

 

[MdB]

(oh and the FPGA has 144 pins, each of which is 0.3mm wide with a 0.2mm gap between it and the next pin. Quite fun to hand solder.)

I have recently had cause to replace some capacitors on my motherboard... and expect to have to replace some more.
The board dates from the 2005 Elizabethan period.
What type of solder would you use to solder the capacitors back in so that the solder flows into the holes?
My first attempts do not look good as the solder refused to enter the holes.
(If you don't mind me asking. )

2005 vintage PCBs could either be lead or lead free. Lead solder will work fine on lead free boards (lead free solder appears to work well on leaded boards but there is a danger of failure due to thermal cycling over time). The most likely cause of your problems is flux. There are many different types of flux that come in cored solder with the better performing types producing the biggest mess to clean up afterwards. The no clean fluxes perform the worst though you can get away with not cleaning the boards afterwards - they are fine for new PCBs and new components but don't work great on old stuff. You then have water soluble fluxes and normal fluxes which require a solvent to get them off. I tend to use the water soluble fluxes as you aren't mucking about with solvent but the results are always good. With the water fluxes, you must wash the PCBs as the flux continues to attack the board otherwise. You can also get paint on fluxes which might be the best for what you are trying to do.

The second issue would be soldering iron temperature. Too cold and the solder doesn't flow, too hot and the flux burns off and the solder doesn't flow. Some lead free solder has a quite a bit higher working temperature than leaded solder so this may come in to it too.

 

[Lime]

Thanks MdB.

 

[philpjuk100]

I am no expert but have had to repair many boards at work and usually bend the tails at 90 deg and try to solder them along the tracks,not always possible I know if you have no clearance on the back of the board. phil.

 

[robgil]

if its audio equipment and you are worried about sound quality i have used silver solder in the past on hi fi equipment , silver wire is also a good idea.

 

[MdB]

if its audio equipment and you are worried about sound quality i have used silver solder in the past on hi fi equipment , silver wire is also a good idea.

Silver solder (2% silver in the stuff I sometimes use) does seem to flow better than normal solder and it is a common ingredient in lead free solders. I very much doubt though it makes the slightest bit of difference in sound quality.

 

[Juju]

I've no idea what the men are talking about. I shall retire to the kitchen and cook my dinner...

 

[Lime]

if its audio equipment and you are worried about sound quality i have used silver solder in the past on hi fi equipment , silver wire is also a good idea.

Silver solder (2% silver in the stuff I sometimes use) does seem to flow better than normal solder and it is a common ingredient in lead free solders. I very much doubt though it makes the slightest bit of difference in sound quality.

I'm pleased you mention the 2% silver solder because that is what I was going to try next.
It cost a fortune.

As for sound quality I spent my youth constructing valve audio amps and I don't think iron wire would have made quality any worse!
At one time I knew nearly every characteristic and pin out of the common high output pentodes, tetrodes and triodes.
Even class A push-pull triodes were very noisy but most of my constructions were push-pull class B fixed bias, sometimes ultralinear.

I miss the banks of upto 8 x KT88s warming the room and producing, if you were lucky, 400watts audio.... but they were real watts unlike the mythical species of wattage measurement prevalent today.

I've read some claims for silver wire in audio, but unless the impedance of the circuit is very, very low, I can't understand what difference it would make.
However as I lost a lot of "top" from my hearing because of my experiments I would not be the best of judges.
Silver was much more common in the valve days for connections and anti-corrosion.
Gold connections may make some difference purely because it does not have an oxide film form on it's surface - and thus create noise - but it doesn't conduct electricity as well as copper.

Hey ho, those were the days.

 

[Penners]

I've no idea what the men are talking about. I shall retire to the kitchen and cook my dinner...

Solder, madam. Your cooker wouldn't work without it! :wink:

 

[robgil]

the silver ive used was in speaker cable , tone arm cable and interconnects so was used for very weak signals. i suppose to be able to hear a real difference you need a really good hifi and room acoustics etc etc but like everything in the world of hifi there is a lot of placebos out there as well.
these for instance will transform your hifi to a whole new level.. (couldn't find a shake my head from side to side emoticon)
http://www.russandrews.com/category-Oak-Cone-and-Spiked-Feet-PSUPPFEET.htm

a lot of electronic equipment as well as cables will have a run in period though , my speaker cable for instance made my hi fi sound pants for the first few weeks , either that or i just got used to it..

 

[MdB]

if its audio equipment and you are worried about sound quality i have used silver solder in the past on hi fi equipment , silver wire is also a good idea.

Silver solder (2% silver in the stuff I sometimes use) does seem to flow better than normal solder and it is a common ingredient in lead free solders. I very much doubt though it makes the slightest bit of difference in sound quality.

I'm pleased you mention the 2% silver solder because that is what I was going to try next.
It cost a fortune.

Yep. Farnell isn't the cheapest source but this is what i've used in the past. I only use it for the very fine work so a real lasts a couple of years which makes the price not so bad. (I'm sure the price was around £30 the last time I bought it though)
http://uk.farnell.com/multicore-solder/smart26-250g-reel/solder-wire-smart-0-46mm/dp/419503

I would never use it for normal assembly. It isn't necessary.

 

[Lime]

I am no expert but have had to repair many boards at work and usually bend the tails at 90 deg and try to solder them along the tracks,not always possible I know if you have no clearance on the back of the board. phil.

The motherboard I'm attempting to make repairs upon is a thick multilayer board and is covered with a thick opaque varnish (?).
Fortunately the capacitors have a little space around them so access is not too much of a problem.
However there is next to nothing to solder onto except the holes.
The biggest danger is my ham-handedness, as anyone who has looked at modern PCBs will know, they are covered in minature easy-to-damage small parts.

 

[MdB]

The motherboard I'm attempting to make repairs upon is a thick multilayer board and is covered with a thick opaque varnish (?).

Probably a conformal coating. Otherwise know as a complete pain when it comes to rework. There are stuff you can get to remove it but it may be worth trying nail polish remover - this may possibly damage some of the components.

However there is next to nothing to solder onto except the holes.

The connections will be on the internal layers and depending on how careful you were on removing the old parts there is a good chance of damaging the board. If any moisture has got in, the heat from your soldering iron can cause the PCB to popcorn or delaminate which is obviously not good either.

If you have lost the pads off one side of the board, you can sometimes solder on to the other side of the board by either mounting the part on the bottom or by putting the part on its side and having longer legs.

 

[philpjuk100]

I am no expert but have had to repair many boards at work and usually bend the tails at 90 deg and try to solder them along the tracks,not always possible I know if you have no clearance on the back of the board. phil.

The motherboard I'm attempting to make repairs upon is a thick multilayer board and is covered with a thick opaque varnish (?).
Fortunately the capacitors have a little space around them so access is not too much of a problem.
However there is next to nothing to solder onto except the holes.
The biggest danger is my ham-handedness, as anyone who has looked at modern PCBs will know, they are covered in minature easy-to-damage small parts.

Yes they can be a bu**er to repair,some of the boards I have to fix are not too old but are obsolete so a "fix" is essential on multi layer board I have glued the component to the board and managed to pick up on a component on the same track(traced from the schematic) it looks terrible but works! So many firms have recently gone bust and Im afraid most of their spares have ended up in a skip.When you have a bit of kit that will cost £20k to replace then a "bodge" can help.There are firms that repair boards but a customer with a non functioning instrument holding up a production line can not wait! phil.

 

[Stephen]

I usually tell people how to fix stuff.

I sometimes tell people how to make stuff.

Generally I pretend to know a lot of things about a lot of stuff, but in reality ......

 

[MdB]

Oh and my accountant (Mrs MdB) has pointed out that one of my jobs is giving advice to people on web forums. If those I have replied to would please send me their billing address, an invoice will be sent in due course.