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PC power source and Spectrums.I'm planning to use a basic PC ATX power source (300W) for all my sinclair equipment, but I have two questions: - I've read about some nasty things …
... nice after I connected a high-power resistor to the +5V ... on the Amiga. Obviously, the voltage-sensor in the psu was ... -
Fastest Baud Rate On A Loader ?Following on (sort of!) from the thread about the best loading.... Which game(s) had the fastest (highest baud rate) ? I seem to remember a couple …
... /> So, applying a fixed DC voltage to the EAR input on ... go high again until you first remove (or reverse) the applied voltage ... -
ULA RAS, CAS cycles, refresh and "snow effect"Hello everyone. I have a question, does anyone observed timings of RAS and CAS generated from ULA? I think there may be answer to where the "snow ef…
... put it's drivers into high-impedance mode for RAS line ... while retrace. Only while high-impedance RFSH via R57 is ... remember there was no such voltage in ZX Spectrum. -
Speccy plus composite modHi folks, I have 2 48K speccy plus machines both with really poor RF output, one is very weak and the other wanders and white tears across the scree…
... collector amplifier has no voltage gain (when we talk ... we're normally talking of voltage gain) - in actual fact ... you have, say, a high impedance output, but you ... circuit to turn the high impedance signal into a ... the same, turn a high impedance signal into a ... -
Eprom blowerdoes anyone know a site with plans for an eprom programmer project that'll blow 27C256s. I attempted to build one called Kisseprom, but the software …
... the margin will not be high enough thus it will fail ... USB also may have unstable voltage that could cause bad data ... USB). This way you get high margin thus better reliability of ... -
I killed my SpectrumMy room was a mass of leads.... and I plugged my NES transformer into my ZX Spectrum +2 accidently, frying it :cry: , am I screwed? or is there somet…
... the current draw was too high, and its unlikely it ever ... it doesnt.
The voltage regulator chip is almost certainly ... one is certainly replace the Voltage regulator chip, a very easy ... -
Loading into the Spectrum's mic socketI was wondering if someone could explain something to me that I've never understood. When loading programs the standard way by connecting a tape play…
... around a 'middle' voltage. This middle voltage will be tamed by ... will oscillate in a different voltage range.
... the recording, and the voltage range the signal oscillates ... voltage range - perhaps allowing the ULA to detect a shift between high ... -
True Spectrum laptop (no emulation)[url]http://user.tninet.se/~vjz762w/[/url] Hi All, I have build a speccy laptop, battery part is not ready yet.... I did it on 2 days, I will put s…
... may actually be the right voltage range and polarity to take ... measuring
voltage during charging was way off too high and there ... -
How to contend memoryHow has this been achieved, electronically? Is there a "memory ready"-line for each bank, or something?
... 0, it is active. 'Active high' means that the pin must ... logic 1, logic 0, or high impedance. A pin in the ... high impedance state is literally off ... the pin is at Vcc voltage (for example +5 volts), ... have all its pins in high impedance state (i.e. " ... -
Z80 ApplicationsI never realised how widely in use the humble Z80 processor was in early Arcade games (Galaga had 3 running in Parallel), Fax Machines, Photocopiers,…
... - plus a high level of integration, single supply voltage (many of its ... -
+2 grey PSU capacitor changeHi I opened up a +2 grey power supply (2.1A max output) unit in order to replace the aged electrolytic capacitor inside, just like I always do with …
... capacitor states the maximum voltage the capacitor can tolerate. ... OK to use higher voltage capacitors (more expensive) ... should not use lower voltage caps than the ones ... spikes (at the 9V voltage output) so unless I ... capacity has to be high enough in order for ... -
+2 grey PSU capacitor changeHi I opened up a +2 grey power supply (2.1A max output) unit in order to replace the aged electrolytic capacitor inside, just like I always do with …
... PSUs that have the same voltage).
The thing is ... it with a fresh and high quality 4700uF instead?
voltage demanding machines, prove that 4700uF ... -
Analogue BeeperThere's been a discussion on foro.speccy.org about multichannel beeper stuff, and since I had the camera out and the scope set up, I set about demons…
... form, and producing that voltage. The beeper circuit is ... is turned into a voltage level), but a PDM ... density is turned into a voltage level. PDM = Pulse Density ... the end is the low/high period in pairs - the ... that the output should be high. It is terminated by ... -
Pera Putnik's RGB interfaceI am sure some (if not many) of you will have seen Pera Putnik's RGB interface [URL="http://members.tripod.com/%7Epiters/uvyrgb.htm"]circuit diagram…
... ) signals are overlayed by DC voltage of about 2.5V. So ... improoved using modern OPVs with high transite frequency. I tested a ... -
Pera Putnik's RGB interfaceI am sure some (if not many) of you will have seen Pera Putnik's RGB interface [URL="http://members.tripod.com/%7Epiters/uvyrgb.htm"]circuit diagram…
... ) signals are overlayed by DC voltage of about 2.5V....
high transite frequency. I tested a ... be no DC load, but high freq. noise will be cut ... -
Which (new) car would you buy?I am thinking of changing cars. After 9 years in my [URL="http://space-car.piranho.de/e/mai01.htm"]Renault Kangoo[/URL] I am thinking of buying a n…
... house. Even at 25kV (the voltage used by electric trains with ... large amounts of power (high voltages and high currents) and creating the ... -
Tape loadersi understand how ROM tape loader works but i dont understand why it so 'complicated'. it measure time until two edges in signal appears. why it does…
... . This biases the average voltage of EAR on the spectrum ... block the incoming dc voltage (ie average voltage) completely. Only the ... resistor network acts as a high pass filter, totally blocking dc ... ears work. The 'dc voltage' or corresponds to constant air ... -
+3 dead(!)Hi, When I turn on my +3 I see only white and black strips (vertical) on screen any idea on how to fix it? Thank you in advance Chris [IMG]http:…
... able to measure a DC voltage of about 2...2.7 ... which is caused by a high frequency signal with a amplitude ... -
+3 dead(!)Hi, When I turn on my +3 I see only white and black strips (vertical) on screen any idea on how to fix it? Thank you in advance Chris [IMG]http:…
... able to measure a DC voltage of about 2...2.7 ... which is caused by a high frequency signal with a amplitude ... -
The Goldfinch updates thread([url=http://www.worldofspectrum.org/forums/showthread.php?t=25034]original announcement thread here[/url] - I figured it was worth starting a new to…
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When the voltage crosses the right threshold for ... with the guaranteed logic level high being around 3 volts (there ... not guaranteed to reach logic high until almost 2t.
< ... reached a level high enough for TTL logic high is sufficient time ... -
Solar power?According to: [URL]http://news.bbc.co.uk/1/hi/sci/tech/8386460.stm[/URL] solar panels are becoming ever cheaper. If these worked well, then of cour…
... />
If there is any high cirrus cloud, the best you ... cloudy days, the almost permanent high cirrus cloud, and the haze ... tomorrow morning (i.e. the voltage of my panel won't ... -
ZX81 more powerful than the Speccy?I have been reading ?The ZX Spectrum Book 1982 - 199x? by Andrew Rollings (thanks again, Andrew - it?s a great read!). There are some comments in the…
... the software driver, and "high level access" to mean writing ... " meaning hardware access, and "high level access" meaning accessing the ... Speccy and BASIC was a high level language, but those ... workbench, with some sort of voltage reader or similar attached).
Spectrum Video Circuitry.Wotcha, I've looking at the circuit diagram of the speccy video circuitry (Hey, I'm snowed in, and theres only so much Civ IV i can stand :p), and I…
... when the Y signal is high (Which i assume means its ... like some sort of reference voltage. I measured it on one ... guess it's just a voltage that needs some external filter ...It is the DR-202A suitable for my Spec +3?Hi, folks! Here is my question. I need a data recorder to load my tape games in my +3. I have located a nice model from Sanyo, the DR-202A but I don…
... datarecorder only runs on mains voltage. :cry:
For use ... max. volume & good / clear high tones. May have to be ...Someone can help me to fix my Zx Spectrum?I did a video about the startup: [url]http://dl.dropbox.com/u/1566495/ZXSPECTRUM03.mp4[/url] I have replaced the ULA with a working one (same proble…
... doing it, I checked the voltage on IC23 Pin 5 and ... 's normal... it's 'logical high' most of the time (> ... , normally close to +5V supply voltage), but with short pulses 'logical ...My Spectrum has gone a bit dud since doing some Mods, HELPMy father in law and I did some modifications to my 48K rubber key Spectrum last weekend, and now it seems to be very keen to crash, especially when …
... ]regulated[/I] DC voltage that's just high enough (around 6~7V ... current-limiting mode, read: output voltage will drop below the normal ...My Spectrum has gone a bit dud since doing some Mods, HELPMy father in law and I did some modifications to my 48K rubber key Spectrum last weekend, and now it seems to be very keen to crash, especially when …
... ]regulated[/I] DC voltage that's just high enough (around 6~7V ...ZX 48K loudspeaker with 8 Ohm possible?Is it possible to change the loudspeaker from the ZX 48K with a model which has only 8 Ohm? Micky
... ). The ULA outputs 4 different voltage levels at the MIC/EAR ... which EAR=0 is not high enough to excite the speaker ...Help, How to RGB to VGA Connector on +2A ?Hi, How would I go about converting the RGB output connector from ZX Spectrum +2/A to VGA type of connector. I found this device [url]http://www.am…
... A/D converter by too high input voltage - therefore there are the ...
