Refurbing an issue one zeddy

[Lardo Boffin]

I forget which wire I used. Most likely 0.63mm dia or 0.9mm dia solid tinned (silver in colour) wire. The 0.9mm is better. If you have any spare off-cuts of telephone cable, or network cable (the type used for fixed wiring), strip the insulation off and that should do.

Mark

I thought I would be clever and made this. Not sure it actually looks better than my previous attempts at joining directly to the original pins but it kept me out of trouble for a while...

I was hoping for nice neat blobs of solder but this strip board was a bugger to solder - it was either all or nothing!

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[sirmorris]

Works for me

[Lardo Boffin]

And here it is fitted.

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A bit of practice I might make it look nicer! I know the case is closed but I still know what it looks like...

One more zeddy nearly ready to go!

I am just waiting for the donor zeddy with (hopefully) a socketed ULA to arrive. Needless to say when the new ULAs are available from the 5 Euro ULA thread I will put that in the donor. No one gets left behind!

Incidentally I am still struggling with desoldering - are 'professional' de soldering stations worth the money?

[sirmorris]

This looks like a bargain. It's a soldering station combined with the grunty pumpy desoldering vacuum that I have as a stand-alone unit.

The desoldering part alone costs nearly the same. I realise it's not impulse buy level but a good tool will be worth the outlay.

[Moggy]

This looks like a bargain. It's a soldering station combined with the grunty pumpy desoldering vacuum that I have as a stand-alone unit.

The desoldering part alone costs nearly the same. I realise it's not impulse buy level but a good tool will be worth the outlay.

Grunty Charlie!! ( sorry private joke)

Yes Lardo A good de-wotsit is worth its weight in gold especially with these boards.

Nice job by the way and why do all your boards look so flaming clean!!?

[Lardo Boffin]

Nice job by the way and why do all your boards look so flaming clean!!?

I buy these off eBay and tend to go for the boxed ones. I assume the majority of these were used for a little bit and then they bought a Spectrum or whatever and put the poor zeddy back in its box and in the loft.

So - more by luck than anything else!

[Paul]

What I use is
this from ebay.
My main problem with manual pumps was always that during the time from taking away the soldering iron and placing the pump the solder was (going) hard again.
With this heated manual pump this doesn't happen anymore.
Works good and is MUCH cheaper.
Kind regards
Paul

[Lardo Boffin]

That is absolute genius Paul! And I can afford one...

It will be months before I can splash out over a hundred quid so this should keep me going.

[1024MAK]

Things I use:-

• ANTEX TCS 50W soldering iron (because it has tips that have a large thermal mass)
• Good solder sucker/pump (and some spare nozzles)
• Desolder braid/Wick
• Desolder iron (like the one linked by Paul)
• Hot air gun (part of a soldering station)
• Electric paint stripper
• Snips
• Thin long noise pliers
• Long dentist type tongs
• Small flat blade screwdriver
• Two sets of helping hands
• Liquid Flux

How/what I use depends on circumstances. If it is a device with three or more pins/legs and I don't want it in usable condition I just cut all the pins/legs off and pull the remains out with the long noise pliers. Then clear the hole with the solder sucker. No damage to the PCB tracks

If I trying to remove a DIL chip and what to reuse it, I use either the hot air gun, or the electric paint stripper while holding the PCB vertically using either the holding hands or another method. After all the solder joints have melted, I gently pull the chip out using the long dentist type tongs. No damage to the legs of the chip, or the PCB tracks

For single sided boards that don't have plated through holes, just a iron & solder sucker are fine. After using the solder sucker, heat up the pin, then use the screwdriver to move the pin away from the tip of the iron so the pin is held in the middle of the hole in the pad. Then after it has cooled, use the screwdriver to check the pin moves freely is is not stuck with solder.

The worst things to desolder are connectors that use thermal plastic and items that either are soldered to large ground or power planes, or which have large tags, or even worst, both

Mark

[Lardo Boffin]

Thanks Mark. Lots of info to digest! I have had the most difficulty so far where there is a large track on the other side. I assume it dissipates the heat too quickly?

Here is take two of the regulator connector:-

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I haven't soldered it yet (too late in the evening now) but I hope I will just get three nice little solder blobs on the top row. Shame I crunched one of the plastic bits while bending the legs out (a bit too narrow for the motherboard)

Basically the connector legs are bent round and pushed back out of the top hole. This leaves enough space for the regulator legs and the whole thing holds itself together nicely.
I don't think I need to solder the bottom row as the pins are connected to the regulator at the top and the shape of the pins gives it strength.

A bit pointless give that it is hidden away but...