Basic problem with transistors

[giftiger_wunsch]

By the way, I made an error in my post reponding to your query regarding the coping saw:
The saw you've selected is fine for PCBs but if you want to cut straight, use a hacksaw.

I've edited the post.

Yeah I noticed you said coping saw twice. And once with a typo


Though the IDC header looks useful, there are two problems:

1) As I mentioned before, I'll want one- or two-pin sockets for the cable-mounted sockets

2) The physical lack of space around where the header is going to be situated means that the boxing around the connectors will prevent it being mounted on the board. Give me a second and I'll provide a photo to show you what I mean. There's very little clearance around the parallel terminals, barely even room for the PCB interconnect headers I linked to before.

 

[Hero999]

Did you checkout the components I linked to?

 

[giftiger_wunsch]

Did you checkout the components I linked to?

I did; see the edited post

 

[Hero999]

So I take it you're going to be using one 26pin header and connecting loads of little two pin cable sockets to it?

I'll have a look for two pin IDC cable mounted sockets.

EDIT:
Short of buying a Molex connector which would also require you to buy 500 or so crimp sockets for £7.90. You could use a PCB mount connector soldered on the end of a piece of cable. It's a bit of a bodge but it'll work. I strongly advise covering the exposed sholder connections with heatshrink sleeving.

**broken link removed**

 

[giftiger_wunsch]

Indeed. Or even single-pin sockets if possible.

[NOOBQUESTION]By the way, what exactly is IDC? Looking at the connectors, it seems to be more or less the same as the headers I was looking at, except it had a plastic frame around the pins. They seem familiar as well... used to be used in computers to connect hard drives etc. I believe...?[/NOOBQUESTION]

Either way, the 36-pin single-row headers I found are cheap and look useful, so really it's just a matter of finding 1- and/or 2-way wire-mounted sockets suitable for use with them.


By the way, here's the photo as promised. Sorry for the large size, that was *after* cropping it down and then setting the image size to 40%. I love my camera

**broken link removed**


For an idea of scale, the holes are 1mm wide and 2.52mm (ish) apart, and the module you see mounted above the board is approximately 8mm above the board.

 

[Hero999]

IDC connectors are just connectors with the pins arranged in a 2.54mm, 2mm or 1.25mm matrix. The headers will mate with ICD connectors.

See my edit to my previous post for a two pin socket suggestion.

 

[giftiger_wunsch]

It's a bit of a bodge but it'll work. I strongly advise covering the exposed sholder connections with heatshrink sleeving.

I was considering that but that seems... complicated. It's surprising rapid don't sell such a common part. Is it worth me asking what a molex connector is by the way?

 

[thepaan]

Molex is a 4 pin power connector providing +12V and +5V that once was the standard connector for nearly everything inside a PC. SATA drives have a new connector (both optical and disk drives) and video cards and motherboards both have different connectors now as well.

 

[giftiger_wunsch]

IDC connectors are just connectors with the pins arranged in a 2.54mm, 2mm or 1.25mm matrix.

If that's all it really is, I think I'll probably just stick to the 2 x 34-pin headers and cut them down to 25 pins each. All I need now is a tonne of 1- and 2-way wire-mounted sockets. Unfortunately the closest I can find are jumper links, which are no good to me

 

[giftiger_wunsch]

I sent a query to rapid, and it seems I'll have to make do with the 2-way variety of **broken link removed**. I'll have to simply solder the wires onto the pins and trim the pins down. Unfortunately these are nearly 8x the price of the 2-way header plugs.

 

[Hero999]

They do, the Molex connector is what you want but you have to buy the crimped contacts separately but these are only available in packs of 500 and cost £7.90 which I don't think you'll be willing to do.

**broken link removed**
**broken link removed**

 

[giftiger_wunsch]

The 2-way housings are £4.50 for 50 and 100 crimp terminals are £3.95, so it shouldn't be too bad... that'll last me a while. The headers are shorter and more expensive and have a raised piece of plastic on one side which may get in the way, but if the pin sizes are the same the housings should be compatible with the cheaper headers I linked to earlier.

The pins on the headers linked to earlier were 0.64mm square, but the data sheet for the molex headers doesn't seem to indicate the actual pin dimensions...

 

[Hero999]

I forgot to mention that ideally you'll need an expensive special crimping tool but you might be able to get away with using pliers.

 

[giftiger_wunsch]

I hope so the contact just needs to be pressed together to bend the incomplete circle of metal around and hold the wire in place right? Sorry, crimping is another thing I haven't yet had to do. A sturdy pair of pliers should do the job, I hope.

 

[Nigel Goodwin]

I hope so the contact just needs to be pressed together to bend the incomplete circle of metal around and hold the wire in place right? Sorry, crimping is another thing I haven't yet had to do. A sturdy pair of pliers should do the job, I hope.

You can solder them quite easily, and in the absence of the proper crimping tool is probably the best method - use pliers to close the cable restraint over the insulation.

 

[giftiger_wunsch]

That should do fine then. Only remaining problem is that the raised plastic portion of the molex header is likely to get in the way, and that they don't sell any larger than 12-way. If possible I would like to use the molex housings + crimp terminals to plug into the cheap headers I was already planning on purchasing, but unless I can be sure that the molex housings will fit over the pins, that may be a bad idea if molex is a standard, perhaps I could find a better data sheet, which gives the dimensions of the pins themselves?

 

[Hero999]

The 2-way housings are £4.50 for 50 and 100 crimp terminals are £3.95, so it shouldn't be too bad... that'll last me a while.

Please post a link to them.

You can solder them quite easily, and in the absence of the proper crimping tool is probably the best method - use pliers to close the cable restraint over the insulation.

Yes you can solder them but I would have never got away with that at work.

 

[giftiger_wunsch]

Please post a link to them.

**broken link removed**

It's just the first link in your post. Note that the 100-packs of crimp terminals are at the bottom of the page.

Yes you can solder them but I would have never got away with that at work.

Good thing it's a hobby project; I'm my own boss if I catch myself soldering it I'll just have to give myself a stern talking-to.

 

[Nigel Goodwin]

Yes you can solder them but I would have never got away with that at work.

Why not?, it's certainly better than not using the correct tool, and probably actually better than using the correct crimping tool.

Or are you talking about the time involved?, crimping is far faster than soldering, which is why it's used.

 

[giftiger_wunsch]

Or are you talking about the time involved?, crimping is far faster than soldering, which is why it's used.

Indeed I did mentally groan at the mention of soldering every contact on, but hey it's good practice and I certainly need it