Sinclair ZX Spectrum +2 Full Restoration
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- Опубликовано: 2 авг 2024
- I'm restoring a grey Sinclair (well, Amstrad rather) ZX Spectrum +2. Turning transistors around, making an RGB cable, recapping, plastic repairs, lots of cleaning, datacorder refurb, adding heat sinks and more. // Sign up for Keysight University Live NOW! bit.ly/Jan_KULive
Tune into the Keysight University Live homepage and the Keysight Labs RUclips channel for the day 1 livestream to get started now!
- Keysight University Live: bit.ly/Jan_KULive
- Day 1 Live Stream (scheduled for March 15th!): • Win Test Gear + Keysig...
- Keysight RUclips channel: / keysightlabs
I already replaced the 78S05 voltage regulator (which is something I would recommend doing) in the previous video!
MUSIC by FOCUS 10 focus10music.bandcamp.com
My video about repairing this Speccy is here: • Sinclair ZX Spectrum +...
My video about the quick 48k Composite Mod is here: • ZX Spectrum 48k Easy C...
PDF about the transistor placement, other fixes and video cables: www.benophetinternet.nl/hobby...
Retro Computer Shack RGB cable design: www.retrocomputershack.com/SC...
Retro Computer Shack eBay store: www.ebay.de/str/retrocomputer...
The simpler RGB cable design I ended up mostly using: www.fruitcake.plus.com/Sinclai...
UHU Plast Special plastic glue*:
UK: amzn.to/3tik1oz
DE: amzn.to/3cqEjpU
Desoldering Station ZD-915*:
DE: amzn.to/3jPh8qC
UK: amzn.to/3rU7WnL
Capacitors for this Spectrum 128k +2 Issue 3 board:
1x 220uF 16V
3x 100uF 16V
1x 47uF 25V
1x 47uF 16V
2x 22uF 16V
3x 22uF 25V
1x 10uF 16V
1x 4.7uF 16V
4x 1uF 50V
Also, 3x 2N3904 transistors
The Datacorder capacitors are:
1x 470uF 10V
1x 100uF 16V
1x 22uF 10V
1x 10uF 10V
TIME STAMPS:
0:00 Introduction
1:31 Issues with Issue 3
2:16 Sponsor Message
3:37 Transistor Issues with Issue 3
8:38 Recapping
12:39 Making an RGB Cable
21:24 Adding Heat Sinks
23:32 Case Disassembly
25:13 Keyboard Disassembly
28:52 Washing Plastic Parts
31:12 Glueing Case Parts
32:05 Datacorder Service
34:48 Reassembly
40:41 Test Run
44:54 Thank you & Good night
This video was sponsored by Keysight.
--------------------------------------------
EQUIPMENT AND TOOLS I USE: kit.co/janbeta *
TWITTER: / thejanbeta
PATREON: / janbeta
WEBSITE: www.janbeta.net
TWITCH: / thejanbeta
YT CHANNEL MEMBERSHIP: / @janbeta
Thanks for watching!
* Stuff marked with "*" contains affiliate links. You don't pay anything extra and I get a little commission from everything you buy through the links (even if you buy something different there).
#JanBeta #Sinclair #ZXSpectrum 
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First! Also, tune into the Keysight University Live homepage and the Keysight Labs RUclips channel for the day 1 livestream to get started now!
- Keysight University Live: bit.ly/Jan_KULive
- Day 1 Live Stream (scheduled for March 15th!): ruclips.net/video/dKYAFzoGgmw/видео.html
- Keysight RUclips channel: ruclips.net/user/keysightlabs
Second. The grey turdtrum is back!!! 🤣😂
@@bufordmaddogtannen And I tried to make it less of a turd! ;)
@@JanBeta I mean... The keyboard is nice, but it still lacks hardware sprites, and a SID chip equivalent.
Once a turdtrum, always a turdtrum. 😁🤣💩
Or maybe the Scheißetrum.
Have you tried desoldering the yellow cable and diodes? That should leave you with the same circuitry as the one the working cable has, but with shielding.
The loading issues is due to misaligned head azimuth, you have to turn the one spring loaded screw on the head till the audio sharpens up then it will load fine
I‘m going to try that. I did get it as far as showing the loading screen in the meantime but the it just reset.
@@JanBeta the best way to do azimuth is by ear, i think. Especially if you have a musical ear :) Simply play a tape and listen to the sound.. the azimuth is best when the sound is "harshest".. where the high frequencies are getting through the best.
For the ultimate loading test, find a game using the Alkatraz loader. These are recognisable by the fancy way in which they load their loading screen. Ghouls n Ghosts and 720 are examples of them
I normally do adjustments by ear too, as soon as the sound goes from muffled to sharp but not super thin, that's where I've found the sweet spot on the spectrum +2
Hi Jan, it seems you actualy made cable for +2A not for +2. +2A already adds intensity to the RGB. If you left out the intensity signal then you probably get just 8 colors instead 16.
13:00 the reason for the diodes is because the Spectrum actually outputs something much like CGA. There is red, green blue and bright signals and they are all at TTL (0-5V) level. The resistors and the diodes are converting this to Analogue RGB levels.
The Spectrum +2 may well incorporate these resistors and diodes already, as they could be built for a variety of different combinations of output on the RGB socket. Usually, they have R12-R14 and diodes D9-D11 installed, so the output is already Analogue RGB. Im a bit surprised Retro Computer Shack's cables show this diagram. Typically there is no Bright signal on the output socket either, it is instead a mono audio out.
To check all this, see how jumpers LK1, LK2, LK3, LK4 and LK7, LK8 are fitted. Most +2's i have seen have LK1 (Pin 5 = VSync), LK4 (Pin 1 = composite video), and LK7 (pin 3 = brightness) installed, as well as R12-R14 and D9-D11 fitted. Annoyingly this means there is no 12V output for scart switching!
Isn't this diffetent just between +2 and +2A? I think all schematics show that +2 should have separate intensity and TTL RGB.
@@rastislavzima Thats what the schematics show, but thats not how they were actually built. All of the grey +2's i've ever seen actually have analogue RGB out because they have the resistors and diodes fitted
@@jaycee1980 thats quite strange if the product is out of specs and you use the wrong cable...
Anyway thanks for the info, I have two +2's waiting for check and refurbishing so I am realy curious what I will find.
The metal clips are usually called Stabilizer Bars, great video Jan!
Thanks! Such specific vocabulary is often a problem for me. ;)
Thanks Jan. Great closing video as normal. Great to see another Specy restored.
For those who want to clean their keyboards but don’t want to risk breaking the plastic, remove the back plate and membrane and soak the remaining keyboard in a bucket with a scoop of laundry washing powder. After a couple of hours most, if not all of the dust and grime will be dissolved, and a rinse under the tap will remove anything left. Soak the keyboard in some fresh water to remove all traces of the laundry powder, and leave outside to ensure all the water inside the keys fully evaporates.
Good idea. A liquid detergent will eliminate the issue of laundry powder traces.
I have been mad Sinclair ZX Spectrum fan, back at the end of 80's. Still have one board in the shed, but do not want to touch it. But thank you for very nice reminder.
Regarding the transistors - i believe the board is laid out for BC546/556 type parts... and in some places they decided to use 2N3904 which have the pinout reversed. Probably a substitute because they were cheaper or something! The ones usually found incorrect are TR4, TR5, and TR7. TR4 stops composite video out working, TR5 stops the VSYNC output working, and TR7 means the CPU is contended in some cases it shouldnt be (it fixes a ULA bug)
Sometimes you find TR4 is a BC5xx and thus the composite video works. The reason your previous attempt to get composite didn't work, is because the RF modulator's composite input has changed to an open collector drive scheme, so the signal is unsuitable for feeding straight into a 75 ohm load, unlike the previous spectrums.
i really should hold my horses before posting early lol. ByteDelight aka Ben Versteeg is absolutely spot on :)
Love your work!
Love the new scope! I find it easier and less risky to remove they keycaps using your fingers, rather than a key cap puller - just based on the way they are clipped in. There's nothing normal about the keys on these lol. Identical to the way they are clipped into the CPC (and the same keys in fact). The safest way to remove them is to remove the back first, then you can unclip them.
Ah, that makes sense, thanks! Yeah, these keyboards are certainly special. After cleaning it feels surprisingly good to type on though I have to say! :D
@@JanBeta Yeah, they are good to type on =D
surprised you havent worked out a sponsorship with cilit bang 😁😁😁😉
Haha, I would be up for that!
Nice workshop lab! I liked this tear-down and restore job. Great video channel too!
Don't be sorry for mispronouncing words, but I'm glad you are willing to learn. Unlike another German RUclipsr that gets angry whenever someone corrects them. I lived in Germany for 12 years when I was a child and fully understand the struggle.
Good video Jan!
Thanks Tommy! :)
Wow, nice score on the Keysight deal ! They do have a lot of excellent community support... its good to see that the big companies have realised that today's hobbyists are tomorrows engineers and supporting them accordingly.
Yes! I was really lucky to get contacted by them. My contact there is massively into elderly electronics as well so we get along nicely. ;)
Thanks for another calming video, Jan. I needed it after trying to set up a wireless laser printer this morning. (The trick was to press and *hold* the WPS button on the router to get them to handshake). I had a 48K in 1984 and a 128K toastrack in 1985 with an Opus Discovery 3.5" drive. Great days... 😁
Haha. Printers have always been one of the more adventurous things to connect to a computer I guess. Kind of funny that they still give us trouble (don’t ask me about setting up my printer on the small network here...)
Amazing video. Love watching you bring a ZX Spectrum back from the grave. Hopefully you can get the datacorder to work correctly.
A BC547 transistor will fit the silkscreen pattern perfectly with the same specs as the 2N3904
Yes, that makes sense. Strange that they changed the transistor type, probably they got the other ones cheaper or something like that.
To combat against steel rust you can use kerosene or even usual car gasoline (aka benzine). It does not dissolve corrosion stain or convert it to metal but it can help greatly with brushing surface, especially if soak for a while.
To fight with corrosion chemically you can use Trilon B. It removes trublesome rust in half of hour or so. But additional safety measures shoud be taken during this procedure.
Thanks for videos. I really like it.
Nice scope you have there Jan! Looks like you have all the best options. You can say I'm jealous now. Yes very nice.
It is a nice scope! The new video is focused on the new scope, too.
Danke!
Hey, thanks so much! :D
thanks
Great job Jan! I still have to repair and restore my +2. It works, but needs cleaning and a recap.
Thanks! Hope your refurb goes well! 🤞
Jan,e un video eccellente,voglio dirti di cuore che sei un tecnico superbo,con un quoziente intellettivo altissimo,ti ringrazio di cuore per i tuoi video.complimenti amico mio,ciao.
Hello j an beta long time no see your videos ,ive being out of home, sick, nice to see your great videos again i have to start backing them to usb stick. you always have intersting vids, ,i have being backing up on a usb stick.it has 256 GB a sandisk..type..
this vid first one to see , this year. keep up great videos...... bye
Before I got a proper effective rust remover, I was using a coca cola with much better success than vinegar. Rust removers and coke contains phosphoric acid, which seems to be pretty effective even in lower concentration (a bit of heat can speed up things noticeably). It may darken the surface quite a bit depending on the material... If available, sandblasting (maybe with some softer medium) has probably better results though...
Good call! I used cola for rust removal on chrome bicycle parts before. Worked really well, didn’t think of using it on computer parts. :D
Regarding cracks in transparent plastics, like in the cassette lid, there are compounds used for repairing car windshields that works. I'ts like a glue with very low surface tension that gets sucked in to the crack and makes it invisible. Have used it a couple of times. Great content as always, Jan!
That’s a good idea, I’m going to get some of that stuff. I even considered trying hot air but I thought it would cause more damage than do any good... :D
Thanks!
Jan, if you want to have a really good looking acrylic tape window, then use "Headlight Restorer & Plastic Polish" , to get rid of the scratches. This works really well and is very simple. It cames with a very fine grid sandpaper, which you first use to sand of a bit of the surface, where the scratches are. Then you apply the paste/cream and use a microfiber cloth, to rub it for almost 1-2 minutes. Than the plastic gets clean and shiny and transparant again. The most scratches are gone. If the scratch is deeper, repeat the procedure... I've done this to the tape window for my Schneider CPC464, it's almost like new again...
I ordered some of that stuff a couple of days ago. I also want to try it on scratched CDs and DVDs eventually. :)
@@JanBeta yes, that should also work on data media like CD-ROM, etc.
Like a couple of other people of said, you need to align the adjustment of the head to the tape, you will hear when it’s in the right sweet spot. It’s particularly a problem with copied games onto blank tapes depending on what gear was used to make the copy.
Breakfast and Jan Beta. Doesn't get much better than this.
Hope you enjoy both! :)
@@JanBeta is it too late to say he was having a jan bagel? i'll show myself out :P
I used a elastic band back in the day
What oscilloscope do you have on your bench Jan?
uuuaaaaaaauuuu
cool
I have one like this one.
I already spoke with some technicians on youtube to see if it is possible to convert the TV output signal to VGA signal
two models were manufactured:
ZX SPECTRUM 128K +2 and the
ZX SPECTRUM 128K +2 A.
A childhood friend of mine had or has +2 A and I still have my +2 that my father offered me.
In Russia (and all around post-USSR) ZX-Spectrum is very loved, there are people who still build clones of it even in 2021 (as programmer I still code in Basic and Asm just for fun in emulator) As a programmer who started to learn programming using ZX-Spectrum 48K (I think I was 7yo, or less, it was 1988 at most since then I seen a lot of architectures, and programing languages) up until today I'm surprised how good Z80 CPU is.
Maybe route the composite signal from the DIN connector internally to the RF out connector? So you have an standard connector anyway.
Yes, that might be the solution.
Poky thing :)
Nice sponserdeal, congrats.
Hi there, hope your staying safe and love the vids as a 8bit to 16bit and 32bit person I’m on a budget and be nice to have your sponsor stuff, but for now have Rigol stuff, sorry 😞
Jan, you can try headlight restorer polish ( a very fine plastic polish) to restore the cassette window.
Ha! I bought some of that a couple of days ago for exactly that purpose. Also want to try it on scratched CDs/DVDs which I heard works wonders. :)
Hello speccy fans, can you help?
The link to the .PDF is broken.
Where can i get a list of components and fixes for my +2 (grey)
Elasticity is the right word
Thanks for the link to that eBay store. ;)
The video signal going to the RF box is mixed with Audio! Unlike the 48k machines. The same is true for the composite video through RGB din. You need to detach the audio by re-connecting a capacitor from the TEA2000 to another point. Google it :)
Ah, that explains that. Thanks!
Hey ! Where do you buy nice quality caps in Europe? I’d like to purchase a small kit to keep around but I don’t know any reliable places to order them from...
I usually order from reichelt.de or conrad.de, both German based trusted electronics parts sellers. I mostly use Panasonic FC and FR series caps.
I recommend remove keys from oposite side under the plate. Just push them out. Much easier and much safier.
26:44 i suspect the keyboard might have suffered a "rage event" at some point - and thats why the mounting pillar and the key pillar broke away. I know MY spectrum certainly suffered a few of those events from me as a child ;)
Haha, yes, sounds plausible. :D
27:40 yep definitely a rage event ;) Or something got dropped onto the keyboard - but i'm betting on a rage event ;)
Jan is an early riser!
Yeah, the kid's back to school after a long period of home schooling now. So I gotta get up earlier again. *yawn*
@@JanBeta oh man, no more sleeping in!
jan
you check the cassette drive?
if it works?
I got it as far as loading the title screen now. Still needs a new belt, I think otherwise it’s fine.
Looking at the first cable and the layout it seems to me that the issue with it is that there was a single diode connected to the three resistors in the scart plug while the diagram shows each resistor being connected to a seperate diode.
I did connect the separate diodes to the resistors. I think I must have shorted something in the cable or the cable was broken before, didn’t test it. :/
Oh dear Jan, youre not getting the bright mode available to 8x8 pixel blocks on the speccy. Thats what the yellow cable with diodes is for! Also watch out because the pinout on the rgb din changes from +2 to +2A/+3! Don't use the same cable - there's a rogue 12v on the +2a/+3!!!
So pausing the vid to read the alternate scart wiring site; looks like later models repurposed bright out to audio out, which explains the first cable not working?
I‘m going to look into that. The retro computer shack wiring is supposed to work on the toastrack and the +2 though. I think I must have messed up something in my wonky cable or it was broken in the first place maybe.
Does your 1084 have SCART? If so, have you tried it on that?
Yes, it’s a SCART model. Haven‘t tried the cable on it though because it still needs some repairs until it works reliably... :D
Ah, the capacitor debate:
FWVLIW I replace all electrolytics as a routine too. I suspect the 'debate' is based in habit. If you are in the habit of using one much prized machine all the time it's reasonable just to watch the caps and only replace them as they go bad - the risk of damaging an old board by changing the caps might be greater than the risk from them leaking. However if like me, and many others, you have a bunch of old computers routinely changing all the caps on purchase really is a must - who knows how often or irregularly it might get used and more importantly checked?
Of course one also has to honestly assess one's soldering skill - in general it's all about practice and patience, although good tools do help. As a tip I can't say how important it is to practice on something disposable before talking on any soldering job and honestly assessing if you / your tools are up to the job. I've been fiddling with this stuff for years but still routinely have a quick practice if it's been a few days since I last played.
I hope that's of help to someone.
PS
I absolutely detest DIN sockets, the number times I've forgotten to thread the plastic sleeve before soldering and somehow I never end up with a neat job. I once made the mistake of designing a USB to C=64 DIN lead so I could get rid of the need for bulky and worrisome C=64 PSU's - all the electronics went inside the DIN connector and, my, they were an utter SOB to do - been running both my C=64's that way for years, the only issue being the rarely used clock doesn't work as there's no sine-wave on the 9v supply. Thankfully they weren't at all popular for some reason so I never made more than a few. (MAX660 if any are curious)
Yes, I completely agree. It definitely makes sense to gain some experience with soldering before you approach something that might be irreplaceable.
There's only really three Spectrum specs. There's the 16k model which I don't think had many games? Then there's the 48k fully loaded model which is where most of the games came, and then there's the 128k spec which also had a 3-voice sound chip, and got some games.
Jan, invest in a paint pen so you can cover up treated metal. If you don't coat/paint metal after the vinegar treatment then it's going to be a waste of time, soon enough the rust will just come back again.
I considered spray painting it but for small parts like that a paint pen makes sense!
Well, other than 2N2222’s, of course. If you stacked up all the 2N2222 transistors out there, it would probably reach the moon. 😏 I don’t know which sold more, the 2N2222 or 2N3904. Both are as common as dirt.
Hey Jan, are you getting the full 15 colours? Without connecting the bout signal/diodes you should only get 8 😀
From what I’ve read, the +2 doesn’t even have a BOUT signal. The diodes seem to be needed only for the toastrack because it outputs TTL signals and not analog RGB. But as I said, I’m a bit of a noob with the Sinclair stuff, I’ll have to double check if I actually get the bright/dark variants of the colours! :D
@@JanBeta The grey +2 is virtually the same as the Toastrack, by default it does output a bout signal it is only the later +2A/B +3 that don't. You can configure it by some links/jumpers:
www.fruitcake.plus.com/Sinclair/Spectrum128/SCARTCable/Spectrum128SCARTCablePlus2.htm
The link explicitly says that the BOUT signal is already combined with the colour signals on the +2 DIN output, it‘s the same link I used to make the second cable.
@@JanBeta Right you are, sir!
Thanks for the nice Work, Jan:)
Wir beide haben die gleiche (alte) Rolle Stannol SN60PB40 ... wir Verbrecher;)
Edit 20:31-> I don't know what the diagram creators thought, but a cable shield may only be connected to a potential (like GND) on one side. Otherwise it is useless because like all other conductors it picks up interference signals along its entire length. The "one-sided" shielding prevents this type of interference and protects the jacketed lines. Hence the name "(cable-)screen"
Ich habe sogar vor ein paar Monaten nochmal Restbestände von dem verbleiten Stannol besorgt. Mag ich einfach lieber als das bleifreie. ;)
I heard about the different approaches to shielding. I think it depends a bit on the use case? There seem to be both "schools" for the shield wiring, not sure what works better for video. From audio stuff I definitely know the shielding is always wired on both ends for those applications. Although there's a "ground lift" switch on many audio devices for breaking ground loops in case you get hum on the signals.
@@JanBeta Well, that school isn't the Bretterpenne? :) Shielding works like all electronics by the law of physics. If you enable a current flow (with both sides on a electric potential) then it isn't a (perfect) shield anymore. It is just another conductor or a loop, prone to noise. This defeats the purpose of a shielding. It is that simple.
Audio: If the shielding is *correct* ... there can't be a ground loop via the shielding .... because dito (see above, it isn't connected both sides, so there can't be a loop) :)
Cables may be shielded continuous when there is a norm or an agreement. Let's say the manufacturer of devices class-A never connects the shielding through ... so that devices of sort B can have it. But that is seldom used. A cable with one end open does the same trick. It doesn't matter which way around it is connected (lets say microphone or old din connectors). The requirement is just open on one side. How around does not matter.
Ich hoffe ich habe alle Klarheiten beseitigt. Gruss, Jed:)
P.S.: Für Leitungen die ihre (gemaschte) Ummantelung als GND oder andersgearteten Rückleiter benutzen gibt es spezielle Namen: Fake, Pfusch, Mist:) Falls das so ist, dann darfst Du diesen Leiter nicht als Abschirmung bezeichnen. Es ist nämlich keine Abschirmung wegen dem Missbrauch als Signalleitung. Ich besitze mehrere Mikrofon-, Gitarren-, Cinch-Leitungen. Mit aussenliegendem Schirm und verdrillten Signalleitern innen. So sollte das eigentlich sein. In der Industrie verwenden wir so etwas dauernd, um z.B. ein Potentiometer am Bedienpult in den Schaltschrank zu führen. Eine doppelte, falsche Schirmung merkst Du in der EMV verseuchten Industrieumgebung sofort. So viel zum praktischen:)
Sorry for the German. Too complicated (for me) to write this in English.
Naja, eigentlich mehr, weil ich nicht die Ohren lang gezogen bekommen will. Unsere engl. Freunde unterscheiden glaube ich nicht zwischen Kabel und Leitungen. ... aber das ist eine andere Geschichte:)
Mehr Info: de.wikipedia.org/wiki/Erdschleife beschreibt explizit was ich oben geschildert habe, auch das verhindern mit "...oder das Auflegen des Schirmes nur an einem Ende der Kabelverbindung." or EN: en.wikipedia.org/wiki/Ground_loop_(electricity)
42:35 tape speed is definitely wrong.. as you say, the belt is worn. Fortunately they are not hard to get, they are 65mm overall diameter with a 1.2mm square cross section. Check out a guy called "JoulesPerCouloumb" - he is not active at the moment, but he has some really good past videos on servicing Spectrums
Yes, I watched quite a few JoulesPerCoulomb videos when I did my first Speccy repairs. He knows the machines in and out it seems. Really great stuff. Thanks for the measurements, too! :)
25:20 Broken post? Hmm. Looks a bit bendy topcenter don't you think - a "manual-stress-relief-mold" sotosay, by the looks of it.
Someone might have finished a session playing "Way of the fist".
check the azimuth is correct as well :D
I will! Got it to show the loading screen in the meantime but then it just resets.
2020/2021 the years us men grew beards. Jan Beta, Linus Sebastian, few others I forgot about and me growing and maintaining (badly) a short boxed beard
14:33 That is not a 180° DIN. 8pin DIN plugs are either 262° or 270°. You appear to be holding a 270.
Yes! No idea why I said 180, must have misplaced something in my brain... :D
@@JanBeta The cable construction page you show mentions it, so you probably picked it up from that.
Aaah, that explains it. Probably got that stuck in my head and didn’t think too much when I talked about the plug. Thanks for pointing that out!
Need to see that Mario game working 😊
I‘m going to keep trying. :)
Time for a shower tray plug donation, I guess! 😉
It has such a weird shape that I wasn't able to find a suitable one yet! But the "wet rag" tactic works fine for me for the time being. ;)
Jan 8-Beta
Hot water trick on belt 🙂
Yeah, might give that a shot.
those bars are called key stabilizers .
Although fond memories of this machine moving from the 48k was the biggest disappointment in my computing life and that's including the CD32, had the 128k spectrum for maybe 8 months before moving on to the Commodore 64 which needles to say blew me away, so many rehashed 48k games on that 128k and even when the game designers tried their best it just showed how the poor old 128k didn't have much to offer above the 48k, don't get me wrong there were improvements but the C64 just blew it out the water.
That infamous cheap Tanashin mechanism, a lot of wow and flutter to me by the sound, see Techmoan channel for info on that mechanism assembly:
ruclips.net/video/nezGOVOpHtc/видео.html
The DIN is the German bit ;)
Deutsches Institut für Normung, yes... :D
Cheap brands of capacitors...How is one to know
It can be hard to tell. There are actually counterfeits that look very real. Your best bet is to buy from a reputable supplier like Jameco or Mouser. They will have done the legwork to make sure the parts are authentic. If you buy from Shenzhen off of eBay or aliexpress then you are 100% getting fake parts.
Did you think we wouldn't recognize the red cap of a fluff box ? 😋
It was peanut butter I think, but pretty close! 😂
Wait a second, so they actually produced these boards with reversed transistors? Meaning they never worked even when brand new? Hard to imagine as why would they not have been returned then... I'm missing something. :) I also don't get the discussion about the caps, even if they're fine, why risk the possibility of one leaking if you can replace them with high quality ones. On my Amiga 1200 I even used dry versions, yes more expensive, but who cares. :)
Yes, that’s what they did. The boards still work and you even get a somewhat proper composite signal with the reversed transistors. Certainly not as well as intended though.
YOU MUST TO READ THIS
My comments are as I watch the videos.
The correct reading has to be exactly the same rotation as if listening to music.
You can exchange the reader for a newer one, but the reading head must be the same or the same. I'm not sure, because mine is in the garage, it is mono reading, not stereo.
HERE ALSO A LINK OF HOW IS THE IMAGE BY READING CORRECTLY.
IF AN ERROR HAPPENS IN READING, THE "PC" GIVES WRITING SIGN AND THE PICTURE IS IN ALTERNATE TONES OF RED / BLACK OR RED / BLUE
When reading correctly, the image remains as it is in the video ....
blue and yellow stripes if I'm not mistaken.
this video is from spain.
but when you see the images you will soon understand what I mean.
I forgot ....
the tape reading head must be well tuned.
because the minimum displacement, many programs will give error in the end.
ONCE YOU HAVE DISASSEMBLED EVERYTHING, YOU WILL HAVE TO DO IT AGAIN, REPLACE THE TAPE WITH A NEWER ONE, BUT THE HEAD MUST BE THE SAME MODEL, AND TUNE WELL.
MY FATHER TUNED THE HEADS WITH HEADPHONES MADE FROM OLD PHONES, BECAUSE IT WAS ALLOWED TO HEAR THE HIGHEST AND CALIBRATE THE READING HEAD ON STEREO MODELS
Mine is all original.
ruclips.net/video/bPTYVCE95dc/видео.html
archive.org/details/softwarelibrary_zx_spectrum
17 min ad from MR JURIS on the vid. Wowzer. Mr Juris makes a dull ad.
I had one for some telescope thing which had technology from Joe Hopkins University. Joe not John? Sounded flaky to me.
Bizarre
The capacitors are out of spec, so they'll have to go out of the Spec, I guess...
Haha! I see what you did there! :D
One might expect that every computer is tested before leaving the factory. If transistors are installed the wrong way, the computer can't work. People in Hong Kong would feel ashamed if there would have been transistors not working, those transistors could have left out of the schematics. The computer could be sold for a lower price.
17:55 wait .. what..??? ....... LG "Life is Good" (Shoutout to @hickok45 :-D )...
What happened to "Phil" - "lips" .. : - |
The LIPS monitor just went a couple of centimeters to the left, I set up a second desk there to have more room for video editing and such. ;)
Scart needs a proper +12v blanking signal? In the +2 Grey this is not provided directly! You would need to modify a link (Jumper) on the motherboard to replace composite out with +12v). This is not clear in your video!!! I think your scart is working simply as a composite out.
No, with my upscaler you don’t need the 12V signal. That’s only needed for some TVs afaik and in most cases you can still switch them to RGB input manually even if it’s missing.
Hate to say it, but as a C=64 guy, the Spectrum stuff looks built like a kids toy. Weak plastics, plastic screws everywhere, the keyboard is overly complicated... And a computer that uses a cassette deck for storage is just too foreign. Great video though!
Jan that's a not proper way to remove keycaps! You have to remove back metal plate (just squeeze plastic tabs), and then just squeeze two plastic tabs for each keycap! For God's sake don't use key puller, it's not commodore/amiga keyboard!
Yes, learned that only when I took it apart fully unfortunately. But, hey, I got away with it (mostly). So it’s good to know that both methods kind of work and you can also work on the keys without taking the whole assembly apart first.
No, no, no ...
when you are going to load a game or program, first .... I repeat ... FIRST play on the tape then enter on the keyboard, because sometimes the mechanical sound of the player is transferred to the memory through the reading head and creates an error when start reading the tape.
REMEMBER ....
FIRST CLIK PLAY ON TAPE THEN "ENTER" THE KEYBOARD.