-
broken 48K, strange screenwell I finally socketed all lower 16K ram chips, (8 of them in a row near corner, not those 4 in two rows) and replaced them with new ones but it did…
... knowing that ULA works, supply voltages restored & lower RAM replaced ... -
Testing memory/transistors etc with multimeterAnyone have a rough guide to show how to do this properly? Im using the diode setting on the multimeter to test various components, im touching the b…
... - you do this by measuring voltages!
For example, you ... help you identify the correct voltages etc.
Of course ... -
Testing memory/transistors etc with multimeterAnyone have a rough guide to show how to do this properly? Im using the diode setting on the multimeter to test various components, im touching the b…
you should test top left pin on RAM chips, too. it should be -5V.
btw, no need to test voltages on each chip (sorry to state the obvious, just to be sure). -
Testing memory/transistors etc with multimeterAnyone have a rough guide to show how to do this properly? Im using the diode setting on the multimeter to test various components, im touching the b…
... v2 board. I get different voltages on my 3b -not a ... -
Testing memory/transistors etc with multimeterAnyone have a rough guide to show how to do this properly? Im using the diode setting on the multimeter to test various components, im touching the b…
... when measuring the (steady) supply voltages, that's a good start! -
ZX Spectrum 48K,issue two - can't get it repairedI have an issue 2, which has some weird very small PCB hanging over the Z80. Some wire go to various places on the big PCB, two go to connections 36 …
My Issue 2 have -4.61V too and it's working. I think voltages are okay. -
ZX Spectrum 48K,issue two - can't get it repairedI have an issue 2, which has some weird very small PCB hanging over the Z80. Some wire go to various places on the big PCB, two go to connections 36 …
... (D16) and then 'takes' this voltages via an 1N4148 diode (D12 ... -
ZX Spectrum 48K,issue two - can't get it repairedI have an issue 2, which has some weird very small PCB hanging over the Z80. Some wire go to various places on the big PCB, two go to connections 36 …
... this part "[quote]'takes' this voltages via an 1N4148 diode (D12 ... -
Testing 4116 and 4164 chipsI have a stash of old 4116 and 4164 chips and wondered how best to test them to see if they work. I don't have a working spectrum to plug them into …
... any fault.
If the voltages are OK, then you should ... -
Testing 4116 and 4164 chipsI have a stash of old 4116 and 4164 chips and wondered how best to test them to see if they work. I don't have a working spectrum to plug them into …
... because they need three different voltages. -
Fuzzy Screen On 48k Spectrum.Hi there. I bought a Spectrum off eBay last week (another for my collection lol), and it suffers with a fuzzy screen e.g. it looks like interference …
... spent quite a while checking voltages and resistance readings etc. with ... reg was reading the correct voltages (in & out) which is ... -
+2A / +2B / +3 Power Supply QuestionIf I'm going to put a switch in the power lines of a +2B, do I need to switch the +5V, +12V and -12V all off to make it safe to remove peripherals, o…
2 48K speccys dead..Hey guys! I've got two of our rubbery friends with me that need some help. They've been like this for some time, but I would like to try and fix th…
... at first but all the voltages seem correct; Aprox. 12V Input ...2 48K speccys dead..Hey guys! I've got two of our rubbery friends with me that need some help. They've been like this for some time, but I would like to try and fix th…
... /> Ok mcleod, I checked the voltages again. From the psu I ... when I plug it. Those voltages you said to check, I ...Some 48k+ packages for saleSoon! Rwap is sending over a few membranes for 48k+ machines, so far, got two fully functional (and looking good!), soon as the membranes are in the…
... but all the power rail voltages are within spec so I ...2 48K speccys dead..Hey guys! I've got two of our rubbery friends with me that need some help. They've been like this for some time, but I would like to try and fix th…
[QUOTE=Diogo;512898]Those voltages you said to check, I ... , right?[/QUOTE]
Indeed check voltages on the lower RAM chips ...2 48K speccys dead..Hey guys! I've got two of our rubbery friends with me that need some help. They've been like this for some time, but I would like to try and fix th…
[QUOTE=RetroTechie;513095]Indeed check voltages on the lower RAM chips - ...Zx Spectrum 48k+ black screenHi A friend of mine gave me his 48k+ and when i tried to turn it on I just get a black screen of the TV. I don't have sound of the console. Where c…
... know what to probe for voltages you should have a look ...Hi everybody! Need help trying to rescue a ZX 48K...Hi, since this is my first post, a bit of info about me: I'm an Italian guy, now living in Poland (Warsaw), informatics and electronic geek since…
As long as all supply voltages (+5V, +12V, -5V) are OK, ...A major revamp of a computerI'm thinking about buying this motherboard here: [url]http://www.asrock.com/MB/overview.asp?Model=A330GC[/url] AFAICT the DIMM slots for RAM are the…
... 4 pins only supply some voltages that are already there, that ...Zx Spectrum 48k+ black screenHi A friend of mine gave me his 48k+ and when i tried to turn it on I just get a black screen of the TV. I don't have sound of the console. Where c…
... know what to probe for voltages you should have a look ...Electronic KitsI'm thinking of building some Electronic Kits as I used to do years ago. Currently scanning [URL="http://www.quasarelectronics.com/"]Quasar Electron…
... a Soldering Gun, the stray voltages that they generate can fry ...Electronic KitsI'm thinking of building some Electronic Kits as I used to do years ago. Currently scanning [URL="http://www.quasarelectronics.com/"]Quasar Electron…
... a Soldering Gun, the stray voltages that they generate can fry ...heatsink on the grey+2anyone ever modded one to run without the heatsink? I know some have on the 48k's but I wouldn't mind removing it from one of mine. If so, any tips …
... , importantly all the stepping of voltages is done externally in the ... , thus no need to regulate voltages internally - thus no need for ...ZX Spectrum +3 Query...Hi all, As common, I brought down my Spectrum from the attic the other day to have another stab at getting it running. I knew from the past it was a…
... /> Have you checked that the voltages are correct when the PSU ... +3 is drawing. If the voltages are down this may indicate ... the 5v supply, the other voltages are only needed by non ...ZX Spectrum +3 Query...Hi all, As common, I brought down my Spectrum from the attic the other day to have another stab at getting it running. I knew from the past it was a…
... be a problem there. What voltages do you measure when the ...ZX Spectrum +3 Query...Hi all, As common, I brought down my Spectrum from the attic the other day to have another stab at getting it running. I knew from the past it was a…
... be a problem there. What voltages do you measure when the ...ZX Spectrum +3 Query...Hi all, As common, I brought down my Spectrum from the attic the other day to have another stab at getting it running. I knew from the past it was a…
... />
[QUOTE=guesser;520762]What voltages do you measure when the ...ZX Spectrum +3 Query...Hi all, As common, I brought down my Spectrum from the attic the other day to have another stab at getting it running. I knew from the past it was a…
ZX Spectrum +3 Query...Hi all, As common, I brought down my Spectrum from the attic the other day to have another stab at getting it running. I knew from the past it was a…
... the +3 only have three voltages +5, +12 and -12.... [/QUOTE ...
