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Getting an 14Mhz crystal to oscillate?I am building a circuit with an 74LS32 and a 74LS193 to work as frequency divider. Though I have hit a snag, how to I wire up a crystal to make it os…
... of the heatsink on any Issue by replace the 7805 with a ... just do it on an issue 2 now since I dont have ... -
Replaced Z80 now a very dark screen!Today I dag out an old issue 3 that ive known for a long time has a faulty Z80 (M1 line) so I heat gunned it out, socketed it and replaced it with a …
... desoldered the LM1889 on my issue 2 128k upgrade machine, and put ... I suspected, I had to replace surrounding caps, including the trim ... -
my first 48kHi I have just got my first 48k and I can't keep it tuned in. And when it is its not very clear. Moving text and switching to black and white. some …
... that bad. Is it an issue 2? If so, VR1 and VR2 ... original electrolytic capacitors, I'd replace all of those. That may ... -
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…
... you just swapped. If you replace multiple chips at once and ... that's more trouble than replace chip-by-chip.
2
[*]schematic of the 48K issue 2
[*]datasheet ... -
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…
... you just swapped. If you replace multiple chips at once and ... that's more trouble than replace chip-by-chip.
2
[*]schematic of the 48K issue 2
[*]datasheet ... -
48k + Spectrum Issue 4S Display IssueHi all! Brand new user here. Growing up I had a zx spectrum for a little bit, and recently I have bought a working 48k + Spectrum (Issue 4). I was…
... guessing I dont need to replace the exact model but make ... same voltage?? So i can replace with much newer ones? Or ... it. Look closely at the issue 4S in the video; it ... ]apart[/B] from C46 in issue 2 Spectrums; the + symbol is on ... -
CapacitorsSorry, another question... I've done a bit of looking around, although after a couple of beers this may not have been as systematic as usual, but I …
... right hand side of the issue 2, where it is always wrong ... />
With reference to the issue 3 Spectrum you are trying ... repair: I do recommend you replace the electrolytic capacitors, but possibly ... that said, I usually just replace all of them before doing ... -
Issue 3 board... How to resurrect?Dear Everyone, Now I have a working 48k Issue 3, a sort of working Speccy+ (still having problems with the keyboard, more of that in another post) a…
... is always good practise to replace all the electrolytic caps on ... as defined per you motherboard issue (1,2,3, etc). The mods ... and sometimes as with the issue 2 there is also an additional ... -
ZTX313 vs 2N2369 pinoutJust for info: [IMG]http://benophetinternet.nl/hobby/vanmezelf/2N2369 vs ZTX313 pinout.jpg[/IMG]
... /> Replacing TR1/TR2 on an Issue 2 sounds interesting. I just wonder ... ), you should be able to replace a low gain group transistor ... -
Which ULA?Just a quick question, more of interest rather than immediate need... I am thinking ahead about the repair of an Issue 2 board, and also an Issue 6A …
... to desolder, clean and replace the Molex clamps for the ... it to replace a suspect ULA in my Issue 6a board ... 'right' ULA for the issue board, so this is ... really want to get the Issue 2 up and running, but ... time to test and replace everything necessary for it ... -
Poorly Issue One 16k spectrum diagnosis?Hello, everyone. :smile: I was lucky enough to buy an Issue One 16k rubber key the other week; I didn't know it was an Issue One till I opened it up…
... #volchk[/URL]
My Issue 2 had display colour issues similar ... you right. (I had to replace VR1 and VR2 also, but ... -
ULAs interchangeable across issuesHi all, Now that I'm retired, I'm looking again at 8 bit computing :) I'm attempting to revive a spectrum 48K. I'm going to swap chips in/out from…
... a 5C112E is used to replace a 5C102E the cockroach mod ... board onwards, so an issue 2 board requires the mod even ... -
Timex 2068 hi-color / hi-res modes.Hello. I know this is not a Timex forum but since it is a very close relative of the Speccy I thought I'd ask my question here. Does anyone know …
... and works fine in an issue 2 Speccy. Sinclair were using the ... to be? Did the QL replace it?
Kind regards ... -
Born again Speccy user with problemsHello all, Firstly I'd like to say a big hello - this is my first post! When I was 8 or 9 or so my dad bought a ZX Spectrum 48K and a whole bunch o…
... ]I found it needs about 2.8 V peak-to-peak ... headphones...
[QUOTE=DEATH]Issue 4B board in an '83 ... - I'd expect an issue 2 or an early issue 3 board [/QUOTE ... make the membrane easy to replace (I wasted no time in ... -
Another "untested" dead spectrum...Hi, I'm looking for some suggestions on a faulty Spectrum I have picked up. I'll need to wait until tomorrow before posting pics, but the screen is …
... supply circuits. Replace the electrolytic capacitors regardless (as the issue 2 board means ... -
Issues with 48k spectrum and divIDEI heard you can have all kinds of issues with 48k spectrum and certain DivIDE models. Is this true and if so what should I look out for ? Only aski…
... 48K models :)
The issue is a bad /M1 line ... to replace the Z80. The overwhelming majority of machines affected are issue ... to use this on an Issue 2, you should be alright. I ... -
48k issue 2I have an issue 2 spectrum 48k and wanted to know if i wanted to change the z80 is ther any fix so i dont have that 1 component hugging the z80 [img…
... also had problems with the ISSUE 2 Spectrum and DivIDE. You have ... probably don't have to replace the processor. It's relatively ... -
I have returned! This time with no tape problems!Hello all. Some of you may remember me from about a month or so ago with this little spawn of satan... :lol: [IMG]http://www.ridgedpixel.co.uk/proj…
... newer cap would be to replace them with?
I ... also plan to replace the regulator as Zorn told ... get pretty warm... My previous issue 2 died from heat/regulator problems ... -
I have returned! This time with no tape problems!Hello all. Some of you may remember me from about a month or so ago with this little spawn of satan... :lol: [IMG]http://www.ridgedpixel.co.uk/proj…
... be blue as standard), and replace with radial or axial components ... />
If it's an issue 2 board then watch out - the ... -
Spectrum 48k ProblemsHi all Got my 48k today but it's playing up abit... First time i turn it on it was like this: [IMG]http://s26.postimg.org/hlg9d3f3d/IMG_20140830_…
... 16K.
And yes, replace all electrolytic caps when possible ... the silkscreen is wrong on issue 2 boards!
Oh, forgot ... -
C46 Capacitor MarkingHi all I've just watched this part of this video: [url]http://www.youtube.com/watch?v=TeCVt2T-YSo&t=17m0s[/url] And he says the marking is incorrec…
... has been incorrect in every issue 2 Spectrum I've seen. If ... way around, you ought to replace it; it will quite likely ... -
C46 Capacitor MarkingHi all I've just watched this part of this video: [url]http://www.youtube.com/watch?v=TeCVt2T-YSo&t=17m0s[/url] And he says the marking is incorrec…
... (although i still need to replace D13 so it won't ... be wrong it's an issue 2. Luckily i have a number ... -
Issue 2 Fuzzy LinesHow can I improve this picture? the colors etc are good but the lines are rather annoying... I'd played with VR1/VR2 but apart from making it nice an…
I've had issue 2 boards where it was impossible ... in this case was to replace both with single turn preset ... -
Noob repairs of an S2 and S6AI received two Spectrums a Series 2 and a Series 6A both of which are not working. I don't know anything about electronics so thought my lad and I wo…
... tinkering :)
For the issue 2, that transistor is referred to ... the transistor was incorporated onto issue 3 and above boards ... to have leaked I would replace it before doing anything ... Speccy 48K board I'd replace all electrolytic capacitors before ... -
Dodgey R62 / D16 on Issue 2?Hello all, I am still beavering away trying to work out why my Issue 2 fails and after a much closer visual inspection I noticed what looks like som…
... />
D16 on the Issue 2 board is a 5v1 Zener ... .
On an issue 2 board I repaired once that ... To fix this, I would replace R62/D15 first, then check ... and replace TR4/TR5 if required. ... present, I'd then replace C46 and D16 in that ... -
Dodgey R62 / D16 on Issue 2?Hello all, I am still beavering away trying to work out why my Issue 2 fails and after a much closer visual inspection I noticed what looks like som…
... doesn't exist on an Issue 2 board - it drives the ... above. If you only have Issue 2 boards, you won't ... /> Assuming you have a few Issue 3 (and above) boards, ... with a ZTX 750/1/2/3 for sure, although ... br />
ZTX 653 will replace a '650. Again, same bit ... -
Ways to identify spectrum issues with out opening them?A good while ago, I'm sure I saw some posts on here about how to identify what issue speccy you have by looking in the expansion port to see what hea…
... bottom. Issue 1 has trimmer adjustment holes for the colour encoder, issue 2 does ... down side, trimmer holes present.
Issue 2: Heatsink down side, trimmer holes absent ... , transistor on CPU.
Issue 3 ... -
Dodgey R62 / D16 on Issue 2?Hello all, I am still beavering away trying to work out why my Issue 2 fails and after a much closer visual inspection I noticed what looks like som…
... suitable for use in an issue 4A board, but I've ... twiddled VR1/VR2 on an issue 2).
If you can ... , this will work in the issue 2, but I would imagine that ... lower RAM IC's to replace, along with possibly a CPU ... -
Finally got round to itFinally got round to giving my old speccy a close look. Details 1982 Issue 2 Seriel No 001 196193 Hmm... Followed the initial tests on You tube w…
... the late eighty's to replace my defunct one ( junked at ... :eek:) and I used the issue 2 before I moved onto PC ... -
ZX Interface 1 Compatability<p>I wondered if anyone knows of any compatibility problems between the ZX interface 1 and certain Issues of the Spectrum motherboard?</p><p>I just p…
... working then I'd just replace the CPU for now. Rare ... an NEC Z80 from an Issue 2 and the IF1 has suddenly ...
