Thanks for this video. I was upset recently when I put batteries in my NC100 and tried to turn it on, only to find it didn't. I watched your video to get some ideas, and would you believe that my problem was also the fuse. It must decay over time, as it was working when I put it away a couple of years ago. Thanks again.
I like how you are so enthusiastic about trying to find a difficult fault and find it disappointing it's such a simple one. Granted most faults usually are simple but still love it. Tempted to send one of my broken pieces of electronics for you to mess about with but I hope it wouldn't take months for it to arrive!
Hi Dave, thanks for this video. I know you have to cater for everybody but I would definitely appreciate more videos on fault-finding retro computers (using a scope to find problems with old CPUs and logic chips, etc.). Thanks.
Love the old school computing, sub 20mhz mostly, vids you do. Commenting at 40 seconds into the video, I know I'll enjoy it. If you ever want something 'Tandy - Radio Shack' to play with, let me know and we'll work something out. Thanks for the fun and all around awesome videos. Now I can rewind the vid and watch what I missed lol.
Very cool. I have CoCo 2's and 3's, hacked and factory stock...I collect and enjoy them...if you ever have a particular want when it comes to Old School computing, I scoop up everything I find here in the US without discrimination and I'm not looking for profit, just keeping the legacy stuff running well. Thanks again for the excellent videos.
I think it’s common for these to have blown fuses because the DC power supply socket has the positive on the outside. People find a wall DC plug that fits, but as most of them are negative on the outside, they blow the fuse.
Hi Dave, Your videos are fascinating, but in my opinion, most of viewers, including me :) are hoping to give us some additional lectures about making and design embedded and electronic circuits, you may have, like for example how to make complex FPGA systems or how to make a double sided circuit at home, ... etc Anything you may have in your huge knowledge will be very useful to us, even it was some ridiculous for you. And I assure the number of viewers will be extremely high.
I used one of those at school because my handwriting was so slow I couldn't keep up with everyone else. I still remember programming it to play pong so while they thought I was working I was just goofing off!
useful thing to note, if you have one of these that doesnt power up, check and if necessary replace the fuse (wickmann type, 0.5amp, if i remember correctly..? ) that some versions of these use(different from the one in the video) as these seem to fail due to age, seem to form some sort of 'fungus' in/on them which rots the internal wire...maybe the version using smd fuse has similar problem!
Fuses just fail the same way as a lightbulb, except much slower - almost every fuse will die in normal use eventually, taking maybe 50 years on average in such use, but there will be some outliers which die early. They consist of thin wire, where molecule scale defects can change with time and cause a small spot which heats up disproportionately, which will eventually be where it burns through.
Waaait a second, the only warm thing on this whole board is the power regulator, and it sits where? 1cm away from the fuse! Well there's your problem. It helps the fuse melt on its own.
Fuses shouldnt just fail with age if the operating current is way below its fusing value...surge currents certainly can cause hotspots and intermittent failure
Crikey. This blows me way, way back to the NTS DreamWriter, a device often used in special education. A friend of mine worked for them up to the point where they began producing Windows CE devices. Crikey, mate! I had almost entirely forgotten about "slabtops"!
Although many devices today can consume much more energy than before, devices have become much more efficient. Back in the 90's there were computers that used 65W, just as your notebook, but they could only calculate far less in a certain amount of time. And besides that, this is an energy efficient portable device from the 90s, that as you stated uses about two watts... which is what an iPhone consumes today.
6v @ .3A = 1.8W Those things really didn't take much to run at all. Its amazing how laptops have gone from that to things like the 65W notebook i'm watching this video on. I know today's computers do a whole lot more, but its just mind-boggling to look at raw differences like that.
Hi, I have a similiar Notepad from Horten it has the same Layout and such but it is not black its just the old PC Gray. The Model is SysLine Pad 1000. The whole Notepad looks just like that Amstrad Notepad.
Someone probably tried to plug the wrong adapter into it, that's the only reason I can think that the fuse would blow without anything else being wrong with it.
it doesnt, it connects to the normally closed switch contact of the dc socket, so disconnects when an external supply is fitted, bridge it with a resistor and you can use rechargeables which charge when externally powered...
Great video. I need information on the flexi cable between the main board and the display. I took mine out a while ago because it was faulty, and can't find it now. Is it a 14 way or double sided 28 way (14 on each side). Looking for a suitable replacement. Cheers. I have an as new Z88 as well, so interesting stuff.
Quote: "And I assure the number of viewers will be extremely high." -> :O Have you looked at the number of his subscribers? I personally am glad that he does NOT show how to make double sided PCBs at home and such. There are plenty of videos of that around already, no need to re-invent the wheel. However, I agree that we didn't get many lectures / tutorials recently and I'd like to see that change as well.
Perhaps they put the Z80 just to be able to run the BBC Basic ... could be ? ... like the C128 running a Z80 appart from the MOS6502, just for the CP/M compatibility .....
Z80 is probably the application processor. There is likely no other processor on the system, as Z80 is power efficient, so the only thing you would gain by including a second processor is more leakage current, a bad idea in a battery powered handheld system. The upgraded model by Nakajima, the ES210, contains a NEC V20 CPU - a much more complex and inherently more expensive device. Makes no sense to upgrade it if it was just there for compatibility's sake. And by the way, porting from z80 to Intel 8086 or NEC V20 is easy enough, little total change should be necessary, and you can do it in a machine language monitor easily enough, or even by directly manipulating the bytes in a binary/hex editor, which is a bit crazy, but can be done if you have to. The huge custom device in the middle probably just routes the signals, does address translation and performs the display refresh, as well as does simple clock switching. There's likely little more logic in there than in the spectrum ULA, with big footprint being merely due to huge number of connections. Maintaining only minimal logic in there is a good idea, because it runs a pretty high clock speed. The z80 actually constantly runs the memory bus, and it has no ready signal from memory, the only way you can prevent it from crashing if you can't deliver it the RAM contents immediately is to halt its clock. So that's what ULA does, it halts the clock while it's doing for example video refresh or other activities that keep RAM busy. A minor modification to that would be to include a register which would allow to stop the clock programmatically, and the clock would automatically be restarted if there's an interrupt, since the custom logic IC is also the interrupt source and RTC host. By the way, that clock burst when running word processor, obviously that software is running on Z80 too.
Considering how little there is in one of those compared to what is in my laptop, I'd argue they're much less energy efficient. My laptop only draws 14 watts while browsing and 40W at load.
Oh...and BTW..I'll trade you a Tandy TRS-80 Color Computer 2 for that Amstrad NC100 put back together and functioning... :) Might make for a cool Tear Down Tuesday. Thx again for the fun videos.
Loved this vid was cheekily wondering if you thought it possible to upgrade the memory on one of these without buying a pcmcia memory card, nice challenge maybe?
This is more comparable to a graphing calculator than it is to a modern laptop. I suspect the graphing calculators win for total battery life, my TI-89 seems to draw between 5 and 80 mA.
Why is it that a computer that only uses up to 60mA needs a power adapter that can go up to 300 mA? Or is that just a standard adapter that the company would just happen to have an excess supply of?
I bet F301 blew because someone stuck the wrong DC power supply on it, or maybe they used one of those universal ones with the 1.5, 3, 4.5, 6, 9, 12V selector switch, polarity changer and the four-way power jack. Ah, memories.
Likely to handle power load and passive components are components that cannot control electrical flow without the help of an active compoment like a transistor.
Hey, i know this is old video, but i just found an old nc100 and the display is so faint =( Anyone knows a solution i can try? already checked the capacitors and they are all seems fine
Hi I have an Acer Aspire 4752. As i press the power button it makes 4 successive clunking sounds followed by one long clunking sound.. The problem started, my frientd took the laptop, as per him, he watche the movies and inserted old DVD. after insertion of few DVDs the pc freezed. so he directly pressed the power button directly. Here's what happened. When I power on the laptop, the boot screen shows up with logo(stuks there) and shows the line press to enter the setup, with the progress bar below, moves up to 75%. When I press F2 or F12, is says waiting.... But the progress bar doesn't go 100%. I tried waiting up to about 30 minutes but there's no luck, the system won't let mo go to setup bios or boot menu. I tried removing the hard disk ang booting it but the same problem occurs. i tried to flash the drive as per some tutorial in youtube but i didn't know which file to rename as the file i downloaded was different from what they showed in videos. Can you suggest me anything I can do? By the way here is my system specs: Intel Corei3-235M Intel HD graphics3000 2 GB DDR3 memory 500GB HDD. DVD drive. Thank you for helping me ou
this isn't really the place to ask this stuff, but try removing the optical drive (it's usually held in place by a recessed screw and then it slides right out, look it up for your particular model) and try rebooting. If you hear the same clunking sound without the optical drive your hard disk might be broken and you need a replacement one with a new operating system.
I almost had one of these. I found it in my teacher's room at the end of school and was told I could keep it. But it was put in with the trash by another student because the case was dirty and he thought it was trash(this kid was stupid) and it was thrown out. I went back at the end of the day to get it and it was gone. Sucks for me.
Subastas Compras Es un fusible, pero no dijo el valor. En los comentarios alguien dice que "cree" que es de 0.5A (500mA). ¡Saludos! (Editado) Perdón, volví a ver el video y sí dice de qué valor cuando muestra el original, está impreso en la placa: 0.8A (800mA). ¡Saludos!
Like I said I love the videos and watch every video posted but at certain points in his videos where his voice pitch goes up and up. Its a little irritating. No disrespect meant besides the 'holyfuck' but then I'm Scottish.. swearing comes naturally unfortunately..
long time viewer, first time poster. F301 is notorious at blewing. I worked in a school and repaired 12 of these (all with same issue)
Thanks for this video. I was upset recently when I put batteries in my NC100 and tried to turn it on, only to find it didn't. I watched your video to get some ideas, and would you believe that my problem was also the fuse. It must decay over time, as it was working when I put it away a couple of years ago. Thanks again.
I like how you are so enthusiastic about trying to find a difficult fault and find it disappointing it's such a simple one. Granted most faults usually are simple but still love it. Tempted to send one of my broken pieces of electronics for you to mess about with but I hope it wouldn't take months for it to arrive!
Hi Dave, thanks for this video. I know you have to cater for everybody but I would definitely appreciate more videos on fault-finding retro computers (using a scope to find problems with old CPUs and logic chips, etc.). Thanks.
Love the old school computing, sub 20mhz mostly, vids you do. Commenting at 40 seconds into the video, I know I'll enjoy it. If you ever want something 'Tandy - Radio Shack' to play with, let me know and we'll work something out. Thanks for the fun and all around awesome videos. Now I can rewind the vid and watch what I missed lol.
Very cool. I have CoCo 2's and 3's, hacked and factory stock...I collect and enjoy them...if you ever have a particular want when it comes to Old School computing, I scoop up everything I find here in the US without discrimination and I'm not looking for profit, just keeping the legacy stuff running well. Thanks again for the excellent videos.
I find it more amazing that they became 3 orders of magnitude faster while only using about one magnitude more power
I think it’s common for these to have blown fuses because the DC power supply socket has the positive on the outside. People find a wall DC plug that fits, but as most of them are negative on the outside, they blow the fuse.
Hi Dave,
Your videos are fascinating, but in my opinion, most of viewers, including me :) are hoping to give us some additional lectures about making and design embedded and electronic circuits, you may have, like for example how to make complex FPGA systems or how to make a double sided circuit at home, ... etc
Anything you may have in your huge knowledge will be very useful to us, even it was some ridiculous for you.
And I assure the number of viewers will be extremely high.
That used to be the case, but now this blog is my day job.
I used one of those at school because my handwriting was so slow I couldn't keep up with everyone else. I still remember programming it to play pong so while they thought I was working I was just goofing off!
I love the strategically placed tantalizing µSupply schematics cameos at around 10:00 and 10:54 ;-)
good video..I especially liked the part where you viewed some of the signals with the ocilloscope.
useful thing to note, if you have one of these that doesnt power up, check and if necessary replace the fuse (wickmann type, 0.5amp, if i remember correctly..?
) that some versions of these use(different from the one in the video) as these seem to fail due to age, seem to form some sort of 'fungus' in/on them which rots the internal wire...maybe the version using smd fuse has similar problem!
Fuses just fail the same way as a lightbulb, except much slower - almost every fuse will die in normal use eventually, taking maybe 50 years on average in such use, but there will be some outliers which die early. They consist of thin wire, where molecule scale defects can change with time and cause a small spot which heats up disproportionately, which will eventually be where it burns through.
Waaait a second, the only warm thing on this whole board is the power regulator, and it sits where? 1cm away from the fuse! Well there's your problem. It helps the fuse melt on its own.
The regulator section barely gets warm..
Fuses shouldnt just fail with age if the operating current is way below its fusing value...surge currents certainly can cause hotspots and intermittent failure
i realize Im pretty off topic but do anybody know a good place to stream newly released movies online?
Crikey. This blows me way, way back to the NTS DreamWriter, a device often used in special education. A friend of mine worked for them up to the point where they began producing Windows CE devices. Crikey, mate! I had almost entirely forgotten about "slabtops"!
"Sagan was here."
Okay Dave, thanks for replay :)
I hope to see more videos from you soon
You have a MakerBot. A missing battery cover seems like a perfect application...
6:35 - 6:40 C340 soldered only by one end? (reference is in the block on the left of the ROM chip)
Although many devices today can consume much more energy than before, devices have become much more efficient. Back in the 90's there were computers that used 65W, just as your notebook, but they could only calculate far less in a certain amount of time. And besides that, this is an energy efficient portable device from the 90s, that as you stated uses about two watts... which is what an iPhone consumes today.
wish u made a teardown of an amiga computer, they were way ahead since 1985 with the amiga 500
6v @ .3A = 1.8W
Those things really didn't take much to run at all. Its amazing how laptops have gone from that to things like the 65W notebook i'm watching this video on. I know today's computers do a whole lot more, but its just mind-boggling to look at raw differences like that.
Hi, I have a similiar Notepad from Horten it has the same Layout and such but it is not black its just the old PC Gray. The Model is SysLine Pad 1000.
The whole Notepad looks just like that Amstrad Notepad.
Someone probably tried to plug the wrong adapter into it, that's the only reason I can think that the fuse would blow without anything else being wrong with it.
interesting to see these old machine come back from the dead , is there a market for these as collectables ?
Thanks from Switzerland :)
Thanks for the offer, but I have a hack in store for the NC100...
One of Lord Sugar's progeny lives on!
Haha, I recently bought this baby. Now it's cool to see how it looks from inside :)
Certainly a good idea to connect the power supply parallel to the non-rechargeable batteries!
it doesnt, it connects to the normally closed switch contact of the dc socket, so disconnects when an external supply is fitted, bridge it with a resistor and you can use rechargeables which charge when externally powered...
Great video. I need information on the flexi cable between the main board and the display. I took mine out a while ago because it was faulty, and can't find it now. Is it a 14 way or double sided 28 way (14 on each side). Looking for a suitable replacement. Cheers. I have an as new Z88 as well, so interesting stuff.
Quote: "And I assure the number of viewers will be extremely high." -> :O Have you looked at the number of his subscribers? I personally am glad that he does NOT show how to make double sided PCBs at home and such. There are plenty of videos of that around already, no need to re-invent the wheel. However, I agree that we didn't get many lectures / tutorials recently and I'd like to see that change as well.
This was rather entertaining. Thanks for the fun...
Amstrad computers had the different colour keys too, I think the enter key was green
Perhaps they put the Z80 just to be able to run the BBC Basic ... could be ? ... like the C128 running a Z80 appart from the MOS6502, just for the CP/M compatibility .....
Z80 is probably the application processor. There is likely no other processor on the system, as Z80 is power efficient, so the only thing you would gain by including a second processor is more leakage current, a bad idea in a battery powered handheld system.
The upgraded model by Nakajima, the ES210, contains a NEC V20 CPU - a much more complex and inherently more expensive device. Makes no sense to upgrade it if it was just there for compatibility's sake. And by the way, porting from z80 to Intel 8086 or NEC V20 is easy enough, little total change should be necessary, and you can do it in a machine language monitor easily enough, or even by directly manipulating the bytes in a binary/hex editor, which is a bit crazy, but can be done if you have to.
The huge custom device in the middle probably just routes the signals, does address translation and performs the display refresh, as well as does simple clock switching. There's likely little more logic in there than in the spectrum ULA, with big footprint being merely due to huge number of connections. Maintaining only minimal logic in there is a good idea, because it runs a pretty high clock speed. The z80 actually constantly runs the memory bus, and it has no ready signal from memory, the only way you can prevent it from crashing if you can't deliver it the RAM contents immediately is to halt its clock. So that's what ULA does, it halts the clock while it's doing for example video refresh or other activities that keep RAM busy. A minor modification to that would be to include a register which would allow to stop the clock programmatically, and the clock would automatically be restarted if there's an interrupt, since the custom logic IC is also the interrupt source and RTC host. By the way, that clock burst when running word processor, obviously that software is running on Z80 too.
the SMT Cap next to R388 is also not soldered to the pad. looks to me as if the wave process sucked the cap to one side not touching the second pad.
I just picked up one last weekend on a flea market. And guess what ... F301 is dead as well. Seems to be the most common error for that thing.
It takes a true engineer to say that it's good when something doesn't work!
Considering how little there is in one of those compared to what is in my laptop, I'd argue they're much less energy efficient. My laptop only draws 14 watts while browsing and 40W at load.
Oh...and BTW..I'll trade you a Tandy TRS-80 Color Computer 2 for that Amstrad NC100 put back together and functioning... :) Might make for a cool Tear Down Tuesday. Thx again for the fun videos.
4:55 whats the difference between a crystal and a resonator? As far as I know with a resonator you don't neet filter caps.
They had surface mount in 1992? I'm actually surprised, for some reason I thought it was more recent than that.
Thanks
Except the BBC Micro actually used a 6502...so this version of BBC Basic must have been ported to the Z80 for these computers?
When are you finishing the power supply project??
Wow only from 87 to 92, and they already started using SMD, I didnt know SMD was being used already by then!
I have seen smd stuff earlier than these..
Loved this vid was cheekily wondering if you thought it possible to upgrade the memory on one of these without buying a pcmcia memory card, nice challenge maybe?
Amstrad had these made by Nakajima of Japan. all their other stuff was made in Scotland.
It doesn't mean it was not possible to make a laptop back then which would just gobble power. It's just what you get when you use stock batteries.
This is more comparable to a graphing calculator than it is to a modern laptop. I suspect the graphing calculators win for total battery life, my TI-89 seems to draw between 5 and 80 mA.
what's with this incredible resolution in the closeup vid? I need whatever is doing that. Oh, and thanks :)
Why is it that a computer that only uses up to 60mA needs a power adapter that can go up to 300 mA? Or is that just a standard adapter that the company would just happen to have an excess supply of?
interesting video this, does this notebook have a built in speaker?
A lot of laptops will use nearly two watts when off and plugged in.
I was 2 when this was made! :D
There is an unsoldered capacitor near R388
I bet F301 blew because someone stuck the wrong DC power supply on it, or maybe they used one of those universal ones with the 1.5, 3, 4.5, 6, 9, 12V selector switch, polarity changer and the four-way power jack. Ah, memories.
Might just be the camera angle, but seems like (R388) isn't soldered on correctly, pad isn't connected.
Miguel Garcia saw that as well, 6:36 C340
why would you need so many resistors and sots all bunched together like that? the 101 and 100s? what do they do, what do you mean by "Passive"
Likely to handle power load and passive components are components that cannot control electrical flow without the help of an active compoment like a transistor.
I guess top faults are Fuse, Cap and then what? Transistor?
Hey, i know this is old video, but i just found an old nc100 and the display is so faint =(
Anyone knows a solution i can try? already checked the capacitors and they are all seems fine
A resonator is made from a piezoelectric ceramic and less accurate than a quartz crystal.
I wish all faults were that easy!
I wonder if you can OC that cpu? or would it die?
Grr, I used one of these while i was in school, and got blamed when the backup battery decided to die and lose everyones stuff.
BURN IT!
Run the keyboard through a dishwasher, set to cold water, no heat dry, and no detergent. Let the keyboard air dry for a few days.
I never understood why a board needs so many little resisters, it makes the board kinda big.
LOL, i'm on the cpc wiki forum
they're still around
12:20 - 45mA D:
2.7 W
Do these have the y2k-bug? :)
First thing I'd have done with it is swap out the resonator for an overclock ;)
Hi I have an Acer Aspire 4752. As i press the power button it makes 4 successive clunking sounds followed by one long clunking sound..
The problem started, my frientd took the laptop, as per him, he watche the movies and inserted old DVD. after insertion of few DVDs the pc freezed. so he directly pressed the power button directly.
Here's what happened. When I power on the laptop, the boot screen shows up with logo(stuks there) and shows the line press to enter the setup, with the progress bar below, moves up to 75%. When I press F2 or F12, is says waiting.... But the progress bar doesn't go 100%. I tried waiting up to about 30 minutes but there's no luck, the system won't let mo go to setup bios or boot menu. I tried removing the hard disk ang booting it but the same problem occurs.
i tried to flash the drive as per some tutorial in youtube but i didn't know which file to rename as the file i downloaded was different from what they showed in videos.
Can you suggest me anything I can do?
By the way here is my system specs:
Intel Corei3-235M
Intel HD graphics3000
2 GB DDR3 memory
500GB HDD.
DVD drive.
Thank you for helping me ou
this isn't really the place to ask this stuff, but try removing the optical drive (it's usually held in place by a recessed screw and then it slides right out, look it up for your particular model) and try rebooting.
If you hear the same clunking sound without the optical drive your hard disk might be broken and you need a replacement one with a new operating system.
Lets Assume.... Up in here, up in here. I'm gonna assume its up in here, up in here..
My uses 200W while gaming.
1mA=.001A so .045A * 6V = 0.27W
Ahhh ok, Thanks
Nakajima? Good God i nver expected a company which manufactured warplanes in ww2 to produce electronics!
1.8W is a lot in comparison though, considering today's laptops are a lot more than 36 times more powerful...
"Boring as bat poo..."? Guano is considered a commodity in some countries...
I almost had one of these. I found it in my teacher's room at the end of school and was told I could keep it. But it was put in with the trash by another student because the case was dirty and he thought it was trash(this kid was stupid) and it was thrown out. I went back at the end of the day to get it and it was gone. Sucks for me.
Hola me paso lo mismo de cuenta es la resistencia que le pones , no entendo mucho de ingles, gracias!!!
Subastas Compras Es un fusible, pero no dijo el valor. En los comentarios alguien dice que "cree" que es de 0.5A (500mA). ¡Saludos!
(Editado) Perdón, volví a ver el video y sí dice de qué valor cuando muestra el original, está impreso en la placa: 0.8A (800mA). ¡Saludos!
gracias por el dato
36 times as much power consumption
well over a million times as much data throughput.
Your videos made me subscribe to you, AT F#CKING SCHOOL
Synthematix It's got a little buzzer in it. Not much.
nobody loves you
Jenna Love c:
hollyfuck you are so wrong D:
I like his voice :P
AlanMichaelSugarTRADing
Like I said I love the videos and watch every video posted but at certain points in his videos where his voice pitch goes up and up. Its a little irritating. No disrespect meant besides the 'holyfuck' but then I'm Scottish.. swearing comes naturally unfortunately..
Please don't