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Re: Replacing the dashboard plastic PCB

Posted: 19 Jul 2018, 14:28
by Chalawandan
Cheers Chris,

The excellent kit was waiting for me when I got home last night, along with some bits and bobs from farnell. I am really excited at the prospect of something new for me - soldering, and want to say a huge thanks for all your hard, transparent efforts on the forum and at home putting this all together. Really glad I read through the whole thread before starting to order up verobaord.

I realise it a long discursive thread, and your kit might not be available for ever, but there's so much in the thread it should at least be linked from the wiki, or a comment on there suggestion? Admin? I nearly went off with the veroboard plan!!

I'll no doubt be back with a few questions during the build!

Thanks again

Dan

Re: Replacing the dashboard plastic PCB

Posted: 19 Jul 2018, 14:58
by CJH
Thanks Dan - glad it got there ok.

Feel free to post questions, either in this thread or in PM, and I'll do my best to answer them in a timely fashion. If you're a total novice at soldering, do have a practice first - a bit of veroboard and some thin wire or cheap components perhaps. A small pack of resistors will cost very little from RS - in fact the PCB kit has more resistors than you need so work out which ones you're going to use and then practice with the spares. Through-hole soldering isn't difficult, but it may take a few goes to get a feel for it. Before I tackled my first proper project some years ago (a hifi pre-amp) I bought some cheap kits from Maplin to practice on, but unfortunately that's no longer an option.

Good luck.

Re: Replacing the dashboard plastic PCB

Posted: 19 Jul 2018, 15:08
by CJH
One more thing:

In the assembly notes I mentioned a trick to hold the components in place while you solder them, which is to splay the legs of the component. I added a highlighted note to say that you should NOT do this if there's any possibility that you might want to unsolder the component, e.g. to change a resistor value for instance. Components CAN be unsoldered with care, particularly if they only have two legs, but this process becomes a LOT more difficult if they've been soldered in with bent legs - there's a much higher chance of damaging the PCB. So I think the better approach is to pre-bend the component legs so that they are parallel, then start with the lowest height components and work with the PCB inverted on top of the components to hold them in place.

Re: Replacing the dashboard plastic PCB

Posted: 19 Jul 2018, 16:34
by slowcoach
A 'solder sucker' tool is essential :-)

Re: Replacing the dashboard plastic PCB

Posted: 19 Jul 2018, 16:54
by CJH
slowcoach wrote:A 'solder sucker' tool is essential :-)

Yep - same as rubbers on the ends of pencils. :ok

Re: Replacing the dashboard plastic PCB

Posted: 20 Jul 2018, 07:13
by CJH
Interesting thread about the oil LED and the DOPS circuit here. Having never seen a foil circuit board for a later van with DOPS I had not realised that the DOPS pcb takes over the control of the oil LED, and therefore the current limiting resistor that feeds that LED directly is omitted.

On my PCB, that direct current limiting resistor is R3, so the conclusion is that if the board is being built up to suit a dash that has a DOPS PCB in the back of the speedo, then R3 should be omitted from the build. I will update my assembly guide accordingly.

Re: Replacing the dashboard plastic PCB

Posted: 20 Jul 2018, 08:37
by Chalawandan
Good to know!

I've got the DOPS. In terms of how it all works is there anything else you need - will read that thread later, but do you need any photos, or multimeter measurements taking or anything to help?

Dan

Re: Replacing the dashboard plastic PCB

Posted: 20 Jul 2018, 10:44
by mike_gee32
My kit has arrived today, it really is fantastic quality and includes absolutely everything you could need (except for someone with a steady hand to solder it for me :lol: ) the documentation is also excellent.

Massive thanks to Chris for the effort he's put into this kit :D

Re: Replacing the dashboard plastic PCB

Posted: 20 Jul 2018, 12:07
by Chalawandan
Maybe a daft question - but I'll need to bridge the PCB where the resistor was with some connecting wire?

Re: Replacing the dashboard plastic PCB

Posted: 20 Jul 2018, 12:13
by CJH
Chalawandan wrote:Maybe a daft question - but I'll need to bridge the PCB where the resistor was with some connecting wire?

No - just leave the R3 location empty. The LED will get an alternative feed from the DOPS circuit.

If I do an update to the board in the future, I may add a jumper so that the resistor R3 can be soldered into place but then removed from the circuit by pulling the jumper.

Re: Replacing the dashboard plastic PCB

Posted: 20 Jul 2018, 12:46
by CJH
Chalawandan wrote:Good to know!

I've got the DOPS. In terms of how it all works is there anything else you need - will read that thread later, but do you need any photos, or multimeter measurements taking or anything to help?

Dan

Thanks Dan - I think the only thing I'm missing is confirmation from someone with a DOPS circuit that the board works as intended. All I've been able to do is a continuity check to make sure the pins connect to the right points in the circuit, as gleaned from online diagrams of the circuit board.

Re: Replacing the dashboard plastic PCB

Posted: 26 Jul 2018, 15:00
by CovKid
Update Chris. Molex connector arrived from Hong Kong (£1.85). Much prefer this method of connection so hopefully at the weekend I can fit this and fully test :D
Will make it much easier for me to unplug dash. Would be handy to have an additional heavy duty plug/socket for all the switches but thankfully the dash pod isn't something you have to remove too often,

Image

Re: Replacing the dashboard plastic PCB

Posted: 26 Jul 2018, 17:25
by CJH
Agreed - that looks like a robust way to connect the loom to the dash, with at least a couple of spare pins. Although, for the sake of avoiding confusion, I should clarify that the original 14-pin multiplug, plus the 'fingers' edge connector in the PCB kit, are easy to connect and disconnect, and they provide enough connectors to attach all the gauges and make use of all six LEDs. The only issue is that one or two (depending on vintage) of the slots in the multiplug may be missing the terminals, so would need them supplying from a second hand connector, as I did, if you wish to make use of the spare LED(s). Failing that, the wires for the spare LED(s) can be connected up directly to the PCB.

Looking forward to hearing that you've got it all working :)

Re: Replacing the dashboard plastic PCB

Posted: 26 Jul 2018, 18:36
by CovKid
The only thing against me is this damned heat, but I'll give it a go :)

Had to abandon brakes/clutch for same reason. :|

Re: Replacing the dashboard plastic PCB

Posted: 26 Jul 2018, 19:46
by CJH
CovKid wrote:The only thing against me is this damned heat, but I'll give it a go :)

Had to abandon brakes/clutch for same reason. :|

Yeah, not pleasant working on the dashboard behind the windscreen when it's like this. I adjusted my rear brakes this evening ready for tomorrow's MOT, and that was quite enough for me.
Took one drum off for a look see (came off no problem at all :run ). By the time I got to the other one I didn't even bother to take the wheel off.