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Not bored with the Boards.Going through some old tapes stored rather badly I came across an unlikely item that that I must have stored away quickly with other low grade items …
... could have been a short circuit I introduced somewhere. Here is ... fail also caused a short circuit in the ROM itself which ... ROM but not power up . If the short circuit is still there ... . If there is no short circuit in the tracking then it ... -
In-game Screen FlickeringHi folks, today while playing 'Beyond the Ice Palace' I noticed strange behavior of my Issue 6a Spectrum+. When I pressed '2' (for UP) + 'O' (for …
... test should be with the power disconnected and done twice. Once ... the meter will indicate "open circuit" (different meters show this differently ... -
What mods do you recommend for a +2aHello all, I have recently got a +2a, that is running nicely. I'm thinking of modding it. I have read that the +3e rom is a good option. what else…
... looks like a normal amplifier circuit is being fed to UM1233 ... modulator! Couldn't you simply bypass UM1233 and feed the output ... -
What mods do you recommend for a +2aHello all, I have recently got a +2a, that is running nicely. I'm thinking of modding it. I have read that the +3e rom is a good option. what else…
... a bit confused but this circuit you are modulating the brightness ... 48k where you can just bypass the RF modulator to get ... -
48k Issue 6a Very sick indeed.Hi Guys. I have a 48k Issue 6a board that shows a white screen with grey border. The white screen has three black squares spaced equally on the le…
... pulsed with current. Hence the circuit is unable to generate the ... in this part of the power supply circuit as a failed electrolytic ... of the resistors in the circuit. Beware however that some will ... being tested while in a circuit.
At this stage ... -
The Crystal MazeDear WOS, I thought about conceptualising a Speccy game based on the classic 1990s game show "The Crystal Maze", which has recently returned to TV…
... button to build up jumping power and release it when it ... the box. After pressing the power button, the box will unlock ... wires to form an electrical circuit and then screws in a ... big battery to complete the circuit.
Mouse? Yes.
48k Issue 6a Very sick indeed.Hi Guys. I have a 48k Issue 6a board that shows a white screen with grey border. The white screen has three black squares spaced equally on the le…
... ' power supply that would not work correctly with the Tr4/Tr5 circuit ...Interference when using modern PSUMy 48k revision 3 spectrum with a basic 1 wire composite video mod works perfectly with the original power supply. However When I use a modern regula…
... UK700, UK1200 and UK1400 Sinclair power supply units (PSU) that I ... , this fuse often goes open circuit.
Silicon diodes are ... a current or a short circuit). If one does fail, it ...Troubleshooting my +2To put this in context: a while back (i.e. late last year and earlier this year) I was looking to put together a compilation of modern Spectrum games…
... 925686"]The problem with the power plug / socket is likely ... the solder spots where the power socket is. It all ... a constant interruption of the power, so it's definitely ... current socket is a circuit board with a gigantic ... the plug around (no power on, but I can ...ZX Spectrum +3 repairI have my first +3 here, and it needs repairs. Hoping someone here can help me out. When I power it on I get this screen with black and white line…
... a power on, then the capacitor and resistor for the reset circuit ...ZX Spectrum +3 repairI have my first +3 here, and it needs repairs. Hoping someone here can help me out. When I power it on I get this screen with black and white line…
... a power on, then the capacitor and resistor for the reset circuit ... work straight away after the power on. I suppose a squirt ...Troubleshooting my +2To put this in context: a while back (i.e. late last year and earlier this year) I was looking to put together a compilation of modern Spectrum games…
... OF THIS! HOT NAKED... ER... CIRCUIT BOARDS! (If your name is ... Z80 has a slightly higher power consumption. I am also rather ... , until I looked underneath the circuit board and found evidence of ... else non-standard on this circuit board that might be causing ...Help with transistor replacement in audio ampHi folks, I'd like to replace two of the transistors in my audio amplifier which I suspect are causing crackling noise in one of the channels. Ori…
... .
In a practical circuit, it is the design of ... the circuit that determines the gain of ... that part of the circuit, as long as the transistor ... solder joints. Both on inputs, power connections and outputs. So I ...My re-creacton of the Z80 8-bit Universal IDEI looked into my draw with various bits & bobs for PC and I found there a CF-IDE adapter, HDD ribbons and two CF cards. So, I was thinking to myself,…
... the case, i replaced the power LED with a dual-colour ... see it. Probably using a circuit off some form of "Electronics ...Send in the ClonesPlease name all the Spectrum clones out there ( I would say I need it back on my desk in 5 minutes , but I will be a bit more generous in this case!…
... ' was a term for a circuit. In which case, how on ... considered a bus—it carries power, which can be shared among ... either ground (“0”) or the power rail (“1”). Think of a ... the air. In an electrical circuit, a wire that is floating ...Nasty vertical pattern on a 128K Toast Rack via RGBI managed to fix the busted membrane on my [url="https://www.worldofspectrum.org/forums/discussion/55755/got-myself-a-128k-toast-rack-plus-a-simple-a…
... that gets onto the +5V power and 0V/GND lines from ... want to use an external circuit, feed the digital RGB outputs ... 128k, but Pokemon sells a circuit for the ZX81 that does ...Nasty vertical pattern on a 128K Toast Rack via RGBI managed to fix the busted membrane on my [url="https://www.worldofspectrum.org/forums/discussion/55755/got-myself-a-128k-toast-rack-plus-a-simple-a…
... want to use an external circuit, feed the digital RGB outputs ... a few caps to the power rail seemed to have toned ...Broken Issue 2 - likely culpritsI've just got hold of an issue 2 spectrum with an interesting layout (heatsink is vertical and goes down to the speaker, some variable resistors and …
... definitely loading one of the power rails way more than it ... . Measure apparent resistance on the power input jack (with the machine ... in diode test mode) in-circuit, but ideally, you’d want ...Broken Issue 2 - likely culpritsI've just got hold of an issue 2 spectrum with an interesting layout (heatsink is vertical and goes down to the speaker, some variable resistors and …
... and Zener diode in the circuit.
The 4116 (or ... renewed. But as the 12V power supply system uses the +5V ...Broken Issue 2 - likely culpritsI've just got hold of an issue 2 spectrum with an interesting layout (heatsink is vertical and goes down to the speaker, some variable resistors and …
... , generally speaking, most of the power related circuitry is okay.
circuit, giving strange results.
Broken Issue 2 - likely culpritsI've just got hold of an issue 2 spectrum with an interesting layout (heatsink is vertical and goes down to the speaker, some variable resistors and …
... [i]before[/i] the first power-on, and compared to the ... get dead shorts or open circuit readings. Admittedly, not as helpful ...ZXBaremulator v3.H(ikoki) BetaHi, Thanks to a Recreated ZX kindly donated by Hikoki, I've added support for it to ZXBaremulator. Now two keyboards can be connected to the PI…
... could be software rather than power related . Why is the software ... site mentions the "re charge circuit" : this has to work with ... assume a certain level of power or not?Opus Discovery not WorkingHello hope you can help, or if this thread goes well that you also find the answers you are looking for... I have an Opus discovery that does not …
... Ribbon cable and the main power cable.
[url ... an understanding of the Video circuit?
Speccy:
[ ... together where missing, the power lead was covered in some ... FDD was disconnected - both power and ribbon cable. However it ...Whats the name of the chip that replaces the ULA?I can't find it through searching using the above title. I distinctly remember reading about a new type of programmable chip that can be set to behav…
... gates. In theory, any logic circuit design can be built with ... want made after you apply power to it, you are close ... blocks are selected just after power up according to data that ...Trying to repair my old 48kAbout 30 years ago I had a spectrum 48k, it had some troubles in the end, it was very unstable when it was cold, so I had to warm it up an hour befor…
... of the DC/DC converter circuit only produces a voltage of ... />
As well as the power connector on the PCB, the ... lead that goes into the power plug also can be a ...Spectrum stuff online "buying skills". Are real skills needed for low cost Speccy items? Firstly , there are some pretty fundamental requirements that are probably too basic to mention , like buying the right software at the right pri…
... say, you need add extra bypass/filter capacitors to a few ... the picture and condition the power rails.Re-created Multiface 128Just bought the bare board from the Bay and am wondering if anybody else on here has built one? Well made PCB, doc files online including a BOM an…
... polarity being dependent on the circuit design. But, I can help ... , they tend to go short circuit. A high current then flows ... to fail. Sometimes, if the power supply limits the current, and ...help with issue 3 48k speccy after recap and new tr4 and tr5I have a 48K speccy that was not working. After recapping and replacing TR4 and TR5 it came back to life However after a short while running weird …
... /TR5 are part of the power supply circuit that supply the 3 ... failures. Wrong polarity from a power supply, or connecting/disconnecting interfaces ...help with issue 3 48k speccy after recap and new tr4 and tr5I have a 48K speccy that was not working. After recapping and replacing TR4 and TR5 it came back to life However after a short while running weird …
... /TR5 are part of the power supply circuit that supply the 3 ... failures. Wrong polarity from a power supply, or connecting/disconnecting interfaces ...what components normally get taken out if you plug+unplug a joystick interface in with the power onwhat components normally get taken out if you plug+unplug a joystick interface in with the power on? i remember doing this a few times when i had …
... the presence of the various power supply pins on the edge ... +5V, you get a short circuit).
[b][i]Mark ...
