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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…
... value. I have also replaced TR4, TR5 and removed all the ... -
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…
... /> You could also double check TR4 and TR5 in circuit with ... -
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…
... be an issue with TR5. TR4 still looks good. I tested ... -
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…
... be an issue with TR5. TR4 still looks good. I tested ... -
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…
You must try to filter out 'shortcircuited' chips that ruin TR4, by monitoring the +12V. Note that chips that cause no short can still be defect, but the ones causing overload must be eliminated first.
Use your current limiter. -
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…
... out 'shortcircuited' chips that ruin TR4, by monitoring the +12V. Note ... -
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…
... of the 4116's. Replaced TR4 and TR5. And when testing ... -
Issue 4S AnnoyanceRecently ive been going through a few interfaces testing them and I stupidly inserted a "key-less" interface (didnt know at the time but should have …
...and I'd suggest replacing TR4 and TR5 and re-checking the voltages -
Issue 4S AnnoyanceRecently ive been going through a few interfaces testing them and I stupidly inserted a "key-less" interface (didnt know at the time but should have …
Thanks everyone, its already composite modded and ive tried the ULA in a working machine, it works so its something else, ill take a closer look at TR4 and 5, sure ive got some spares of those somewhere -
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…
... well as assorted replacements for TR4 etc... I can see this ... -
Strange and faulty toastrackI just got hold of a toastrack, which is kind of strange. First of all, when I opened it, I spotted a socketed ULA and ROM, which is good, however, t…
... diode test? If so, remove TR4 and check it, it's ... -
ZX Spectrum Microvision - REAL retro setup!Some fun pictures. In reality the picture looks some better and more readible, but the camera doesn't pick it up well. [IMG]http://benophetinternet.…
... even socketed the toroid and TR4 and 5.
I also ... -
ZX Spectrum Microvision - REAL retro setup!Some fun pictures. In reality the picture looks some better and more readible, but the camera doesn't pick it up well. [IMG]http://benophetinternet.…
... even socketed the toroid and TR4 and 5.
I also ... -
another faulty zx spectrum +2 to fix!!!Hello to all, I'm new here... I have got a faulty +2 (gray) and start to try fix it... I have read the treads of xaris_sm and Pluto63 as background…
... psu
2) turned TR4 by 180 degree and relink ... -
ZX Spectrum Microvision - REAL retro setup!Some fun pictures. In reality the picture looks some better and more readible, but the camera doesn't pick it up well. [IMG]http://benophetinternet.…
... test board.
Closeup shows TR4 and 5 and the toroid ... -
ZX Spectrum manufactured by SAMSUNGI just got hold of a 48K ZX Spectrum Issue 4S of which was manufactured by SAMSUNG. I was not aware that Samsung manufactured Spectrums under licence…
... position's to fit the TR4 transistor. One of the position ... -
Strange and faulty toastrackI just got hold of a toastrack, which is kind of strange. First of all, when I opened it, I spotted a socketed ULA and ROM, which is good, however, t…
... " ZTX213 and ZTX651, de-soldered TR4 and TR5 and replaced both ... -
Spectrum+ Noisey Picture ProblemHi fellow Spec-chums I need your help! I've recently brought a 48K+ Spectrum(issue 6A) that I'm trying to repair. I did all initial tests on it prio…
Good to get some feedback after a successful repair. I learned something new today, after my recent video signal experience with TR4/TR5. Thanks! -
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 …
... sorting out the voltage regulator, TR4 and Coil on the issue ... -
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 …
... doing the work on the TR4, coil and voltage regulator for ... -
Correction of +2 hardware errorsThis is a collection of various pieces of information picked up from various places, including a lot from this forum. I have edited it and reworded i…
... have done the switching of TR4, and removed C31, and the ... -
Spectrum +2(grey) rf problem not tuning inHi lads, first of all a quick intro. Im a speccy enthusiast in Ireland, had my first speccy when i was seven in 1987(grey +2). Eventually it got repl…
... probably due to a shorted TR4 transistor. It is located just ... on the board for the TR4 was printed backwards, so the ... TR4 transistor is fitted in reverse. ... of transistor used for the TR4 on the +2 greys, but ... -
Spectrum +2(grey) rf problem not tuning inHi lads, first of all a quick intro. Im a speccy enthusiast in Ireland, had my first speccy when i was seven in 1987(grey +2). Eventually it got repl…
... corrections thread, it seems the TR4 transistor I mentioned is only ... -
+2 issue oneI can't remember seeing this model board before, so here we go: [IMG]http://benophetinternet.nl/hobby/vanmezelf/20130605_153957.jpg[/IMG] [IMG]http…
Mine looks like this. The tr4 is off to the right and down from the rf mod. Tr1 and 2 are so close theyre touching. Mod datecode is 8422. -
The Spectrum Resuscitation ThreadKicking off this thread as a place where people who are fixing/restoring Spectrums (or indeed any other piece of related hardware) can show off their…
... are signs of rework around TR4 and the LM1889 has been ... , so it looks like the TR4 failure took out the LM1889 ... -
TR1 and TR2 replacementCan anyone tell me the correct replacement part for these? This is for an Issue 4S btw
The orientation is printed on the silkscreen of the board but I just wanted to be sure due to another transistor (TR4 I think) having to be fitted the other way round on a 4S if you replaced it -
TR1 and TR2 replacementCan anyone tell me the correct replacement part for these? This is for an Issue 4S btw
I'm more-or-less certain the transistors I suggested will work for all NPN transistors in the 16/48K Spectrums, apart from use as TR4 or TR7. The pin-out may not be the same as the originals - I can't remember, you'll have to check datasheets. -
Issue 4A repair attemptI think I need some help. I have a nice Issue 4A main board here, which does not give out any video signal. I checked some voltages (the ones that se…
... , the entire lower RAM and TR4/TR5 all show expected readings ... -
Issue 4A issuesHi all, I've been trying to get the Issue 4A board that came DOA with the case I purchased for my Frankenspectrum to work. I've recapped and socket…
... swapped out, and TR1/TR2/TR4/TR5 swapped for spares (which ... -
Repairing a torn trace on an Issue 2 PCBI've found what I think could be the reason for my Issue 2 board not working properly... There is a torn PCB trace beneath one end of where a new ULA…
... and b) PSU centred on TR4 ZTX650.
Faulty RAM ...