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Issue 1 schematics?I'm fault-finding an issue 1 board. So far I've found a hot memory chip and snipped it's supply legs, then swapped the burnt-out 7805 for a switched…
I'm fault-finding an issue 1 board. So far I' ... if anyone knows of a schematic, that would greatly help. -
Faulty Issue 1Hi all, thought I'd document my efforts in getting another speccy working. I've never done this before so please bear with me... I recently took a p…
... one off of ebay ("missing power supply - unable to test" ... installed. Lo and behold - initial power on reveals duff 7805 and ... with a Traco Power DC-DC convertor. Power on and I ... worldofspectrum.org/forums/discussion/51557/issue-1-schematics#latest"]here[/url ... -
No colors on screen, issue 2.I have a 48k issue 2 with composite mod. When i first pluged it in after i bought it, the screen went yellow and after restart there were no colors a…
I have a 48k issue 2 with composite mod. When ... no success. Any ideas? The power suply is also replaced. -
Laptop issueMy laptop seems ti have died, i noticed yesterday when i switched it on there was no hard drive activity and the screen was blank, even though the po…
... was blank, even though the power light was on.
I ... if anyone knows what the issue could be, is it worth ... -
Spectrum issue 4SI have an almost completely depopulated issue 4s board. Wondering what to do, repairs or spares? I hooked it up and the voltages are off, 5v is fi…
... have an almost completely depopulated issue 4s board. Wondering what to ... to find a schematic and layout. The 4ab schematic is similar but ... -
ZX Spectrum issue 4B acquiredI recently acquired a ZX Spectrum with serial number 138-363292 on the case, and a 1983 issue 4B board I got it for the purpose of repair. and have…
... the case, and a 1983 issue 4B board
I got ... />
I have yet to power is on but i was ... -
Issue 2 problem.Hi all, I'm trying to repair / upgrade an Issue 2 Spectrum for a friend, but have come accros the following problem. When I power the machine …
... trying to repair / upgrade an Issue 2 Spectrum for a friend ... problem.
When I power the machine on I get ... the odd thing, if I power up with the Sinclair test ... -
No CLK on issue 2 ULA pin 32I'm trying to fix an issue 2. The symptoms are as follows:- Black and white bars on screen, colours near impossible to tune in, although these po…
... 'm trying to fix an issue 2.
The symptoms ... /> I'm looking at the schematic and starting to suspect the ... -
Power Play Joystick InterfacePower Play Joystick Interface for the ZX Spectrum. This is a Kempston compatible interface. Address decoding Any IO address where A5 is low... …
Power Play Joystick Interface for the ... - always 0[/code]
Schematic circuit diagram:
[img]https ... -
Issue with TV signal + Inductor Coil (16K Issue 2 Speccy)Hello guys, I just got a 16K Issue 2 Speccy from eBay. It was sold as not working so I knew there would be some work needed before it's working ag…
... /> I just got a 16K Issue 2 Speccy from eBay. It ... . Then however I noticed an issue with TV signal which normally ... basic measurements (this time with power on) and the only result ... two videos - one showing the issue with TV signal and another ... -
Fixing a poorly Issue 3 - Odd faults.Here's one for you Spectrum fixers, I warn you it's a long one. I've spent a couple hours this evening doing several repairs on a rubber keyed Speccy…
... on a rubber keyed Speccy(issue 3) that I can't ... . First thing I did was power the Speccy up and connect ... -
Fuller FDS Keyboard schematicAnyone have a schematic for that? Mine is randomly triggering BREAK on powerup or Symbol Shift in BASIC. I guess it comes down to one of the CD4016 …
Anyone have a schematic for that?
Mine is randomly triggering BREAK on powerup or Symbol Shift in BASIC. I guess it comes down to one of the CD4016 having gone bad, but a schematic would certainly help pinpointing the issue. -
48K Issue 2 RAM issuesI have 48K issue 2 board (I've checked, the upper memory is present!). It's not very well. I've not attempted to diagnose one before, so please bear …
I have 48K issue 2 board (I've checked, ... me.
If I power it up, I get colourful ... block pattern corruption. If I power it up with a DivMMC ... -
Help request for an injured Issue 4A spectrumHi folks, I'm hoping to resurrect an issue 4A spectrum that has been in my hoard for a couple of decades since buying it for spares. Someone ha…
... 'm hoping to resurrect an issue 4A spectrum that has been ... still hot happy with the power - it makes a slightly odd ... -
48k issue 4B display problem etchi,, i have a zx spectrum 48k issue 4B with a display issue it has wavy lines in both the border and paper,some colours seem worse than others ie red…
... zx spectrum 48k issue 4B with a display issue it has wavy ... few red lines. re applying power results in successful boot every ... composite mod with the same issue.. i have tried everything short ... -
Quirky nerdy hardware quiz time[b]Quirky nerdy hardware quiz time[/b] [list=1][*]How many transistors are on the issue one ZX Spectrum PCB? [color=#FFFFFF].[/color] [*]Which d…
... transistors are on the issue one ZX Spectrum PCB ... s special about the ZX81 issue two board?
[ ... [*]What’s the rated power output of a Sinclair UK1400 ... [*]What’s the normal power factor of an old style ... Spectrum +2A/+2B/+3/+3B computers can be configured ... -
Noisy display faultI've been given an Issue 3 48K Speccy PCB which is in good working order except the main display area has slight changes of shade loosely following a…
... electrolytic cap in the video power supply might be kaputt or ... way to cap heaven. ***quick schematic check*** Check C44 and C45 ... and you do have a power supply issue. Both my Speccies are ... Issue 6, so no coils...
The schematic I ... -
toasted soeccysHello, ive jsut bought a pair of speccys on ebay (one 16k issue 2 & a prob 48k issue 3) unfortunaly the genius who sold them tried to see if the wor…
... schematics for an Issue 2 suggests that the power supply that generates ... (+12v) is a switch mode power supply, which gets regulated by ... -
Original Kempston interface on a +3Hello everyone, if i insert an original kempston interface in the extension port of a +3 should it work or not? I tried it and the machine didn't bo…
... that deamn amstrad placed the power supply connector too close the ... and some pin (in the power supply jack) doesn't ... is enough space for the power supply connector and the ... /> My +3's board has "issue two" written on it, does ... or not? Is this the +3B version? -
Original Kempston interface on a +3Hello everyone, if i insert an original kempston interface in the extension port of a +3 should it work or not? I tried it and the machine didn't bo…
... ;deamn amstrad placed the power supply connector too close the ... pin (in >the power supply jack) doesn't ... ;enough space for the power supply connector and the ... +3's board has "issue two" written on it, ... not? >Is this the +3B version?[/QUOTE]
... -
I/O on the Speccy - ideas/help wanted!I'd like an interface for the Spectrum that can control and monitor other items. I have a task in mind that would require: A: 4xbinary inputs (as in…
... />
3. Look up the schematic for the Kempston, you can ... software. There's also the issue of noise on the inputs ... how you drive your outputs. Schematic here:
[url]http://www ... gets capacitatively coupled via the power MOSFET doesn't do something ... -
Flicker fixer for ZX 48KHas anyone the schematics for the flicker fixer: [URL]http://8bit.yarek.pl/computer/zx.48/[/URL] Micky
... /> Pictures belong to a 4B issue board, but this will do ... /3B. Not sure if the traces are the same place in issue ... work OK with a 4A issue board and a SGS brand ... a piece of wire and power on. If it boots, ... actual mod tested on a issue 4A board.
[ ... -
Timex 2048 documentsHi, I got Timex 2048, seems to work, but no colors on screen :cry:. Neither TV out, nor Composite works. ULA fault ? It seems TC 2048 uses MC 1377 a…
... board, however matches logic for issue 2, crazy...
I ... images/tc2048_5c.JPG[/url]
Issue 5d:
[url]http:// ... investigate loading issue, however I think my Timex has some power problem ... /> Since I have issue 3 that matches schematic I am going to ... -
+2A/+2B/+3/+3B researchdoing my redrawing/correcting of the +3 schematic I'm uncovering lots of oddities in the service manuals. I am trying to work out what really exists…
... +2A/B circuit boards (ISSUE 1 and ISSUE 2 both number Z70833 ... , as found in the "+2B/+3B" diagram of the +3 amendment ... are many differences between the schematic from the "+2A +3" diagram ... them are errors as the schematic has several other obvious errors ... -
+2A/+2B/+3/+3B researchdoing my redrawing/correcting of the +3 schematic I'm uncovering lots of oddities in the service manuals. I am trying to work out what really exists…
... ;480849]you've found a schematic showing the transistor circuit instead ... FM modulator on the +2B ISSUE 4?
can you ... called plus3 for spectrum +2B/+3B
if you want ... photo of bruno's spectrum ISSUE 4 1990
[url ... -
Spectrum +3, Issue 2...I have just had plonked on my desk a nice issue 2 Spectrum +3. I'm not sure if its 100% working yet, as I have not plumbed it into a telly. So, assu…
... on my desk a nice issue 2 Spectrum +3. I ... board says it's an issue 2. Does this need ... that the "3b" is fine, is this the issue 2 +3 ... ?[/QUOTE]
Both Issue 1 an Issue 2 motherboards have the ... leaks interference onto all the power and ground lines.
... -
ZX Spectrum not working... issue 4S?Hi, I've bought a "new" broken ZX Spectrum +. The idea was to put an harlequin board inside, but for the moment I'm trying to put it in working order…
... currently configured. IIRC issue 4S is mostly like issue 4B, but ... a datasheet that includes the schematic symbol, so that it' ... easy to compare against Spectrum schematic. Base-collector-emitter is what ... it's killed instantly @ power-on. Also easy to overheat ... -
The Disciple clone... doable?Hi. As a spectrum user in the 80's this was the dream interface all-in-one for me. I have a 48k+ and planning on get a 128K toast-rack later. Anyway…
... the ROM. It is an Issue 3 rom IIRC.
... articles in Format Magazine (Issue 3.01 onwards) for ... see in Format volume 3, issue 4, page 11:
... there when next we power up the Speccy.[/QUOTE]< ... would seem to contradict the schematic on WoS, although perhaps ... -
Spectrum 128k +2 grey RAMhi all, the manual say that ram ic's should be KM4164B-15P but when i open my spectrum (not repaired by anyone) the ram chips was KM4164B-12 is thi…
... chip and one or more power rails... (and perhaps a few ... Spectrum +2
[*]schematic of the 48K issue 2
[*]datasheet for ... -
Spectrum 128k +2 grey RAMhi all, the manual say that ram ic's should be KM4164B-15P but when i open my spectrum (not repaired by anyone) the ram chips was KM4164B-12 is thi…
... chip and one or more power rails... (and perhaps a few ... Spectrum +2
[*]schematic of the 48K issue 2
[*]datasheet for ...
