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Issue 3B turning offI'm trying to save a Spectrum Issue 3B. I restored the power supply section, changing the 7805, TR4, and TR5, besides all electrolytic capacitors. No…
... trying to save a Spectrum Issue 3B. I restored the power ... works for about one or two minutes, then it turns off ... -
Upper memory issueZX Spectrum 48K, issue 2, boots fine. Lower RAM OK. When tested with the new test ROM in the Diagboard, for all upper RAM tests "FAIL" is shown. I…
ZX Spectrum 48K, issue 2, boots fine.
Lower ... problem.
IC22 is socketed two, if I take out the ... 's (5C112E) with another, working, issue 2 PCB.
Replaced ... -
Retro Gamer's star letter (issue 164)The star letter in this month's Retro Gamer (issue 164) "[i]Dear RG, What on earth has happened to the Spectrum community? Sites such as World …
... this month's Retro Gamer (issue 164)
"[i ... surrounding the new Vega (with two camps forming) so it’s ... -
Replacing lower RAM 4116 ZX Spectrum 48k - desoldering advice please?A long post, but interesting pictures perhaps. :) I'd like some advice: (also apologies I think I picked the wrong 'Hardware' category for this, plea…
... to indicate a lower RAM issue. It hadn't been ... one. I suspect that two at most of the current ... 't think there's any issue with the tracks.
... socket and new 4116 and capacitor and bridge, I was still ... correct approach to solving this issue, or am I on the ... -
Issue 2 colour quality modsI think this question must have been asked before but my choices of search terms can't find an answer. In the service manual under Issue 2 modific…
... /> In the service manual under Issue 2 modifications it says:
Issue 2 boards or are there ... just curious as I have two Issue 2 mobos with the original ... -
Spectrum 48K / composite mod / LCD TV: voltages out of the ULAHello Spectrum World I have juste bought again my first computer on ebay... a Speccy 48k issue 2 with a 5C112E-2 ULA. Just had to replace TR4 and …
... on ebay... a Speccy 48k issue 2 with a 5C112E-2 ... the composite modification (with the capacitor and then with a NPN ... 250us long sync pulse between two frames).
I would ... -
Converting Issue 2 keyboard games to Issue 3Dipping back into the World of Spectrum (and no, not just this site) I was wondering if I could do a machine code job myself without having any under…
... others) - which required an Issue 2 keyboard to gain any ... I've only ever had Issue 3 (and beyond) ... are being checked but only two values are returned - possibly ... V and B on Issue 2 and 3 respectively) ... other programs that require an Issue 2 keyboard to work, ... -
Sinclair User issue 127: Great Eight 16 - what happened?I've been trying to make sure I have an as-near-to-complete-as-possible collection of Crash, Sinclair User and Your Sinclair covertapes (at least as …
... MIA on WOS is SU issue 127: Great Eight 16, which ... and two from YS that are provided this way, but SU issue ... -
48K Issue 3B slowly fading over 15-20 seconds, capacitor gets hot.Hi folks, Recently my much-modified* RAM testing 48K board failed with a hot/burny smell so I turned it off quickly for looking at later. Thinking…
... powering the board and the capacitor marked on the pic gets ... -
12V missing on an issue 3I’ve been working on an issue 3 Spectrum +. It shows thin distorted vertical stripes on bootup. +5 and -5V are all right but the 12V line measures ro…
... ’ve been working on an issue 3 Spectrum +. It shows thin ... the 12V line measures roughly two volts. I’ve already desoldered ... -
16pf Capcitors for C72/C73 issue 3b. Can I use 18pf?Looking at the service manual it states to use a 16pf ceramic disc capacitor in positions C72 and C73 on issue 3b boards. Is this very critical in bo…
... ceramic disc capacitor in positions C72 and C73 on issue 3b boards ... -
rubber troublejus got 48K rubber speccy into my possesion, which was my first computer back then but only for few months before daddy decided to upgrade it for 48+…
C27, the large capacitor to the right hand side ... upper RAM block. On an issue 4 PCB, its directly to ... IC 19.
Take two wires, solder one to the ... -
Best replacement for ZTX650?What is the best replacement transistor for the obsolete ZTX650? I've read that TIP31 will do the trick. Is there a decent equivalent from the BC or …
... I think.
Right, Issue 4 boards were a hotch ... the point where the two diodes and the capacitor connect together, one ... it and also replaced the capacitor that was damaged.
It ... -
Audio input on a +2would it be possible to connect an external tape recorder to the socket at the back,or would something bad happen?
@piters: Well, not just a capacitor, but usually a resistor, too :-) ... (a 100nF - presumably ceramic disc capacitor, and a 10k resistor). This ... - the difference between the two is really just the filter ... resistor.
On the issue of +2 fried ULAs, the ... -
Video output (48K)Hello! I've made video mod on my Zx Spectrum. Now the problem of scanning (and tuning) to right channel is history for me. But, now I have another …
... thing is that I've two Spectrums with this effect. There ... be one hardware issue. Try the fix with the capacitor on LM1889 ... -
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…
... months on my +3 and issue 2 Spectrums.
The ... momentary switch connected across the capacitor to discharge it. The reset ... you might find. As the capacitor charges, the voltage at reset ... of the circuit and spent two days confusedly banging my head ... -
I bought my first ZX Spectrum 48k, now what ?Hi guys ! I recently go to Brussel in Belgium and found a ZX Spectrum at a "flea market" (sorry, I don't the correct word for that, let's call it a …
... the modulator case). Sometimes a capacitor is added (to remove DC ... 48K Speccy.
The two red wires soldered to the ... seem illogical, since all Spectrums issue 2 and above already support ... -
Repairing a faulty 48K issue 2.I am investigating one of a pair of non-working issue 2 48K Spectrums that have been sitting in a cupboard untouched for quite a few years. I haven…
... in blue in the second two.)
I can ... on a problem free Issue 2 that has NEC ... the Spectrum+ nor the good Issue 2.
I ... Issue 2 has had the resistor value change and additional capacitor ... just noticed that the good Issue 2 lacks R57, but ... -
Repairing a faulty 48K issue 2.I am investigating one of a pair of non-working issue 2 48K Spectrums that have been sitting in a cupboard untouched for quite a few years. I haven…
...
No, on an Issue 2 at least, C54, if ... the terrible crime of changing two things at once. At ... change and addition of a capacitor) as recommended in the ...
It does appear the Issue 2 Spectrum went through a ... done away with after Issue 1, but it clearly ... -
Repairing a faulty 48K issue 2.I am investigating one of a pair of non-working issue 2 48K Spectrums that have been sitting in a cupboard untouched for quite a few years. I haven…
With regards the issue 6 circuit board, have a ... motherboards delay the /RAS through two NANDs configured as inverters. You ... too small. Also with that capacitor, a low pass filter is ... -
Issue 3B only sees 16k (and RAMTOP NO GOOD on loading)A ZX+ with issue 3B board that i got recently, does not see anything more than 32768 (sometimes 37267..) on "PRINT PEEK 23732 + PEEK 23733 * 256 (Ent…
... =Asure;610297]A ZX+ with issue 3B board that i got ... the top RAM. Specifically, these two chips store bits D6 and ... PCB. Some issues put that capacitor in the solder side rather ... -
Computer repair questionAn ewgf-style post: I'm usually able to find my way around things, search online for solutions and a few other things, but this time I'm unsure of w…
... . The fact that just two years ago another hard drive ... ) and I do see two capacitors leaning slightly and one ... say for sure that a capacitor is bad just by looking ... SATA ports could be the issue, is it worth using ... almost a week without any issue, and as soon as ... -
Spectrum 128K & Philips CM8833Hello to everybody, My Philips CM8833 is one of my favourite monitors of all time, as it accepts connections from anything I can think of with the e…
... issues, but there is another issue you may not have noticed ... 't help with the vsync issue.[/QUOTE]
Luckily all ... that signals are brought, with two 470R resistors, to a summing ... to ground. Then, a 10uF capacitor picks the signal from the ... -
+2 grey rf out problemI got a kind of broken +2. it basically works, but with a annoying rf out problem. When screen goes black (eg. after border 0: paper 0 command) it l…
... transistors??????? Which are the other two and what do they cause ... Ingo...
As for the capacitor.... can you tell me which ... I get stable RGB on two grays (out of three) on ... all 3 grays are identical (Issue 3) -
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 …
... this is becoming a major issue over the last few years ... the electrolyte came out. The two caps on the bottom right ... sre bulging out and the two on the left seems ok ... be so high that the capacitor will cease to work, although ... -
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…
... issue 1 and 2 you have variable resistors and a variable capacitor ... circuits.
the variable capacitor is to trim the frequency ... leave that well alone. The two variable resistors adjust the levels ... -
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…
... t understand, why does my Issue 4A have 22uF/16V capacitors ... the voltage rating of the capacitor is greater than the ... for two reasons, first, if the voltage on a electrolyic capacitor goes ... Components/22uf-25v-Axial-Electrolytic-Capacitor-11-0125"]here[/URL] ... -
Buzzing Grey +2This is mentioned in another thread but I thought I had best start a new one regarding this. Basically Ive done TR4, put a 5.5k resistor to R38 and …
... , it must be a grounding issue though as it only happens ... amplifier needs a big electrolytic capacitor to get a smooth power ... line. Switching this big capacitor to the 5V line would ... a capacitor of 100pF from this line to ground. In two cases ... -
Spectrum+ Issue 3b customization and repairHi everybody, I've got a Spectrum+ that shows exausted electrolytics capacitors issues such as poor colors on the screen and speaker noises. I was go…
... be safe to proceed with capacitor replacement.
Your screenshot ... conversion circuit on Issue 3 machines (you'll see two implementations of ... involved in this fix during capacitor replacement, that they are replaced ... -
Opus Discovery "the big switch on" (after 20 years)I have a few of these Opus Discovery's with different Eproms in that have not been swiched for 15-20 years or so . I am in no rush to switch any on …
... can easily tell the two transformers because the smaller ... them anyway. The two big capacitors close to ... should also renew the two small 10Uf capacitors next ... single most disturbing reliability issue in the Discovery is ... goes from the big capacitor to the 9V ...
