A cautionary tale !

Tool suggestions, soldering tips, general useful electronics knowhow.
User avatar
supaduper
Posts: 561
Joined: Thu Nov 08, 2018 12:05 pm

A cautionary tale !

Post by supaduper »

I have had a nightmare last couple of days, and was testing TF330s it on my trusty old CD32 , but it broke with a problem with the mouse pointer disappearing and artifacts on the screen and the composite output was lost and that made it unusable, I thought I had shorted something as I had to push one board harder than usual to fit, anyways I broke out the second CD32 and was testing another TF330 when calamity !, I had the same problem with the pointer and graphic artifacts !, so that was number 2 CD32 was broke too:(

So after some thinking I honed in on the RGB to scart cable I use which is like all the ones sold on Ebay, being that the cable goes into the hood and is rather loose, so opened it up and yep it was a mess inside with wires shorting by the looks it had and shorted something out on the CD32s

Cut a long story short I aint no board expert but I methodically checked the composite circuit back to Lisa and Alice chips as I was still getting the RGB ouput on the riser, not having a Scope i used a Logic probe and saw there was no CSYNC out of ALICE pin 80 and it also deals with some of the AGA graphics and mouse sprite

So I have ordered two ALICE chips and lets hope its that

Moral of this story is if you value your retro hardware then always check those RGB cables, and what I did was open the two I had and checked them and resoldered the connections inside the hood and used heatshrink tubing to keep them secure and wound more tape around the cable where it enters the hood So there is no play when you clamp the hood down
User avatar
rubber_jonnie
Site Admin
Site Admin
Posts: 10465
Joined: Thu Aug 17, 2017 7:40 pm
Location: Essex
Contact:

Re: A cautionary tale !

Post by rubber_jonnie »

It's good advice, and for me, I have given up buying cables on eBay now and either make my own, or get them from somewhere like Coolnovelties:https://Coolnovelties.co.uk who make a decent cable, and I've recently been made aware of RetroGamingCables:https://www.retrogamingcables.co.uk/ who seem to be getting a good rep.

Hope your Alice replacements do the trick.
Collector of many retro things!
800XL and 65XE both with Ultimate1MB,VBXL/XE & PokeyMax, SIDE3, SDrive Max, 2x 1010 cassette, 2x 1050 one with Happy mod, 3x 2600 Jr, 7800 and Lynx II
Approx 20 STs, including a 520 STM, 520 STFMs, 3x Mega ST, MSTE & 2x 32 Mhz boosted STEs
Plus the rest, totalling around 50 machines including a QL, 3x BBC Model B, Electron, Spectrums, ZX81 etc...
User avatar
GadgetUK164
Posts: 430
Joined: Fri Jan 04, 2019 2:26 pm

Re: A cautionary tale !

Post by GadgetUK164 »

Ouch =/ This is one of the concerns I have with some of the older risers. No isolation on signals =/ I hope that fixes them both - let us know!
My YouTube Channel - www.youtube.com/GadgetUK164
User avatar
supaduper
Posts: 561
Joined: Thu Nov 08, 2018 12:05 pm

Re: A cautionary tale !

Post by supaduper »

rubber_jonnie wrote: Thu Feb 11, 2021 9:18 am It's good advice, and for me, I have given up buying cables on eBay now and either make my own, or get them from somewhere like Coolnovelties:https://Coolnovelties.co.uk who make a decent cable, and I've recently been made aware of RetroGamingCables:https://www.retrogamingcables.co.uk/ who seem to be getting a good rep.

Hope your Alice replacements do the trick.
These were both from coolnovelties :) check the cable see how lose it is going into the hood, I just wound insulation tape around it till I could just about close the hood around the cable so it good and secure with no movement
terriblefire
Moderator Team
Moderator Team
Posts: 5368
Joined: Mon Aug 28, 2017 10:56 pm
Location: Glasgow, UK

Re: A cautionary tale !

Post by terriblefire »

supaduper wrote: Thu Feb 11, 2021 9:55 am These were both from coolnovelties :) check the cable see how lose it is going into the hood, I just wound insulation tape around it till I could just about close the hood around the cable so it good and secure with no movement
order up some heat shrink insulation.. or i'll post you some.
———
"It is not necessarily a supply voltage at no load, but the amount of current it can provide when touched that
indicates how much hurting you shall receive."
User avatar
supaduper
Posts: 561
Joined: Thu Nov 08, 2018 12:05 pm

Re: A cautionary tale !

Post by supaduper »

Thanks for the offer Steve but will not need any as I have a drawer full of the stuff lol

Here is a pic of my fix, look a the free play of the cable going into the hood on the left and my fix on the right, that cable aint moving anywhere :lol:

9JghYXi.jpeg
9JghYXi.jpeg (253.6 KiB) Viewed 1118 times
go0se
Posts: 403
Joined: Sun Nov 25, 2018 7:55 pm

Re: A cautionary tale !

Post by go0se »

DB23 cables breaking internally is inevitable unfortunately, especially if you are plugging and unplugging them regularly to test cards or different Amigas. I've had a few go more than once but fortunately I haven't had any catastrophic damage (that I am aware of!) caused to anything else from the cable breaking.

With these cables I now attack them with hot glue as a preventative measure. Don't bother using the glue gun as everything cools down and solidifies too quickly to make a decent job of it. Instead cut up a hot glue stick and melt it in position with a hot air station. Obviously finding the correct temperature here is important as we want the glue to melt sufficiently but not the connector hood!

We are dealing with this hood design :
DSC_0846.resized.JPG
DSC_0846.resized.JPG (53.78 KiB) Viewed 3189 times


Open cable hood by removing the two recessed screws on the flat 'grip' portion of the hood.
DSC_0848.resized.JPG
DSC_0848.resized.JPG (54.5 KiB) Viewed 3189 times
Cut a standard hot glue stick into 8 roughly even discs and place three towards the rear of the hood in the clamp space. (Decent sized scissors work well to cut up hot glue sticks)
DSC_0849.resized.JPG
DSC_0849.resized.JPG (49.28 KiB) Viewed 3189 times
Using a hot air station, melt the glue discs by choosing an appropriate temperature and air speed on your setup e.g. 110C and medium. Keep the wand well away from the target initially and slowly bring it closer until you see the glue discs starting to melt. Keep a close eye on the hood plastic for any signs of warping or melting, this shouldn't happen at sensible temperatures, but don't go crazy.
DSC_0850.resized.JPG
DSC_0850.resized.JPG (49.14 KiB) Viewed 3189 times
Once the glue discs are fully and evenly melted replace the cable clamp into position in the hood. You should have around ten seconds to play with here as both hood and glue are up to temperature and will take a while to dissapate. This is the advantage of using the hot air station rather than the glue gun. Most glue guns will only just melt the glue and it will cool rapidly when applied. By the time enough glue has been dispensed the initial glue will have started to solidify, resulting in a mess. The hot air station is a much better approach.
DSC_0852.resized.JPG
DSC_0852.resized.JPG (52.05 KiB) Viewed 3189 times
Place three more glue discs on the top of the cable clamp.
DSC_0854.resized.JPG
DSC_0854.resized.JPG (52.43 KiB) Viewed 3189 times
Melt with hot air as before.
DSC_0855.resized.JPG
DSC_0855.resized.JPG (56.65 KiB) Viewed 3189 times
Close up the cable, if you are not overly concerned about aesthetics you can add two more glue discs to the gap at the rear of the cable where it enters the hood.
DSC_0859.resized.JPG
DSC_0859.resized.JPG (49.81 KiB) Viewed 3189 times
Carefully melt the inserted glue discs at a low temp, again using caution not to melt the hood.
DSC_0862.resized.JPG
DSC_0862.resized.JPG (53.26 KiB) Viewed 3189 times
This should change the stress point of the cable and make it last considerably longer. It probably will still break eventually with heavy use but the failure should be inside the cable around the entry of the hood rather than in the hood itself resulting in shorts. If the cable does develop a fault in future it is easy enough to open the glued hood up, pick out the hot glue, shorten the cable by three of four cm, re-solder and reinstall.
User avatar
rubber_jonnie
Site Admin
Site Admin
Posts: 10465
Joined: Thu Aug 17, 2017 7:40 pm
Location: Essex
Contact:

Re: A cautionary tale !

Post by rubber_jonnie »

supaduper wrote: Thu Feb 11, 2021 9:55 am
rubber_jonnie wrote: Thu Feb 11, 2021 9:18 am It's good advice, and for me, I have given up buying cables on eBay now and either make my own, or get them from somewhere like Coolnovelties:https://Coolnovelties.co.uk who make a decent cable, and I've recently been made aware of RetroGamingCables:https://www.retrogamingcables.co.uk/ who seem to be getting a good rep.

Hope your Alice replacements do the trick.
These were both from coolnovelties :) check the cable see how lose it is going into the hood, I just wound insulation tape around it till I could just about close the hood around the cable so it good and secure with no movement
Odd, never had a problem with their cables.
Collector of many retro things!
800XL and 65XE both with Ultimate1MB,VBXL/XE & PokeyMax, SIDE3, SDrive Max, 2x 1010 cassette, 2x 1050 one with Happy mod, 3x 2600 Jr, 7800 and Lynx II
Approx 20 STs, including a 520 STM, 520 STFMs, 3x Mega ST, MSTE & 2x 32 Mhz boosted STEs
Plus the rest, totalling around 50 machines including a QL, 3x BBC Model B, Electron, Spectrums, ZX81 etc...
User avatar
supaduper
Posts: 561
Joined: Thu Nov 08, 2018 12:05 pm

Re: A cautionary tale !

Post by supaduper »

rubber_jonnie wrote: Thu Feb 11, 2021 10:19 pm
supaduper wrote: Thu Feb 11, 2021 9:55 am

These were both from coolnovelties :) check the cable see how lose it is going into the hood, I just wound insulation tape around it till I could just about close the hood around the cable so it good and secure with no movement
Odd, never had a problem with their cables.
Ignore what I said about Coolnovelties cables , I got mixed up :) they were another brand of cable
User avatar
rubber_jonnie
Site Admin
Site Admin
Posts: 10465
Joined: Thu Aug 17, 2017 7:40 pm
Location: Essex
Contact:

Re: A cautionary tale !

Post by rubber_jonnie »

supaduper wrote: Thu Feb 11, 2021 10:22 pm
rubber_jonnie wrote: Thu Feb 11, 2021 10:19 pm

Odd, never had a problem with their cables.
Ignore what I said about Coolnovelties cables , I got mixed up :) they were another brand of cable
Okey dokey 😁
Collector of many retro things!
800XL and 65XE both with Ultimate1MB,VBXL/XE & PokeyMax, SIDE3, SDrive Max, 2x 1010 cassette, 2x 1050 one with Happy mod, 3x 2600 Jr, 7800 and Lynx II
Approx 20 STs, including a 520 STM, 520 STFMs, 3x Mega ST, MSTE & 2x 32 Mhz boosted STEs
Plus the rest, totalling around 50 machines including a QL, 3x BBC Model B, Electron, Spectrums, ZX81 etc...
Post Reply

Return to “ELECTRONICS”