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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 …
... be a bad component or IC that's fried (although generally ... excessive current - I think 4116 RAM could fail in that way ... -
Spectrum Issue two problemI managed to bring back to life a issue two spectrum (at least the power supply cirquit). The screen is now crystal clear (after replacing all the el…
... has to be lower 16k ram, because the machine reaches the ... display (barely readable)
3. Faulty ribbon connectors onboard
4 ... -
Spectrum Issue two problemI managed to bring back to life a issue two spectrum (at least the power supply cirquit). The screen is now crystal clear (after replacing all the el…
... fixed it completely.
Add faulty LM1889N chip to the above ... was only one faulty memory chip in the upper RAM.
Thank ... -
Spritual successor to the Speccy1988-1995 - Atari ST/STe/Falcon 1995-2000 - ? hmmm ? 2000-2006 - Playstation 2 with a keyboard 2007- ?
... />
Either your memory is faulty, or I wasted a lot ... not dealing with 48K of RAM, 15 available colours and a ... -
Did I killed my Speccy ???Hi guys, 1 minute ago I was working on my 128 +2A... But I made a mistake : I cut the gound on the PSU plug of the computer, and I forgot to resolde…
... highly indicitave of them being faulty.
NOTE - they ... equipment.
NEw RAM chips can be got off ... t just solder in the RAM) and then fit the ... new RAM chips. Power up and ... to initialise a 32K upper RAM block :( Day three at ... -
Did I killed my Speccy ???Hi guys, 1 minute ago I was working on my 128 +2A... But I made a mistake : I cut the gound on the PSU plug of the computer, and I forgot to resolde…
...
[QUOTE=DEATH;172500]4464 RAM chips mnore than likely. Hot ... highly indicitave of them being faulty.
NOTE - ... .
NEw RAM chips can be got off ... just solder in the RAM) and then fit the ... new RAM chips. Power up and ... -
Dead Spectrum +Hi all, I've recently dug out my old Spectrum + with the idea of repairing it. When I last looked at it, when I was much younger, I was soldering a …
... pins of the 4116 RAM (awful devices that require ... If you're unsure of IC pin numbering, the datasheet ... also worth checking that RAM chips aren't getting ... these values (a hot RAM indicates it's fried, ... which would indicate failed RAM rather than failed power ... -
Dead Spectrum +Hi all, I've recently dug out my old Spectrum + with the idea of repairing it. When I last looked at it, when I was much younger, I was soldering a …
... the hole. Then I fit IC sockets.
I ... enable logic for the upper RAM (I think it's ... wrong) first for testing upper RAM, since this will disable ... the cases where upper RAM is merely returning bad ... common failure mode of RAM is to just return ... -
toasted soeccysHello, ive jsut bought a pair of speccys on ebay (one 16k issue 2 & a prob 48k issue 3) unfortunaly the genius who sold them tried to see if the wor…
... pins of the 4116 RAM (awful devices that require ... If you're unsure of IC pin numbering, the datasheet ... also worth checking that RAM chips aren't getting ... these values (a hot RAM indicates it's fried, ... which would indicate failed RAM rather than failed power ... -
Features that emulators don't haveI believe most of us use more than one emulator, mainly because there isn't one emulator that has all the features we need or want to use. We also kn…
[QUOTE=chop983;177347]I'd like to see 32k Ram Pack emulation while in 16k mode[/QUOTE]
Oh, and I want to see faulty upper RAM emulation for the 48K model...
Si -
Features that emulators don't haveI believe most of us use more than one emulator, mainly because there isn't one emulator that has all the features we need or want to use. We also kn…
[QUOTE=obo;177352]Oh, and I want to see faulty upper RAM emulation for the 48K model...
Si[/QUOTE]
How about dodgy power supply emulation whilst we're at it? -
TV Modulator. Can it be repaired?Is it possible, to repair tha TV modulator (after removing it) if it gives wavy picture? I replaced both transistors (tr1/2) and both electrolytic ca…
... you overclock your processor and RAM you can do the same ... it's bad upper RAM, but the RAM has not only been ... even done it in order (Ic 22 on the test machine ... , going to IC slot 22 on this one ... -
Anybody fancy coding this?blah de blah de blah Please ignore, poting error.
These days, use flash - don't bother with eprom. You can replace the ROM by making an external board that connects to the edge connector, and nails ROMCS high just like ZX Interface 2, so that the on-board ROM never gets selected. Simple decoding logic ... -
Whats up wi mi speccy ? M RAMTOP no good 0:3I bought a speccy on ebay tried to load Mission Impossible but about 30 secs into loading it stopped and i got the error message ... M RAMTOP no good…
... a 48K with missing upper ram, not a real 16K machine ... find someone has harvested the ram chips from it. I have ... and its upper ram is socketed, if all the IC sockets are ... -
Whats up wi mi speccy ? M RAMTOP no good 0:3I bought a speccy on ebay tried to load Mission Impossible but about 30 secs into loading it stopped and i got the error message ... M RAMTOP no good…
... a 48K with missing upper ram, not a real 16K machine ... find someone has harvested the ram chips from it. I have ... and its upper ram is socketed, if all the IC sockets are ... -
Dead +2B, help required...It was bought defective on ebay. It came with two faults: a "dead" power supply (it was the fuse) and a faulty main unit. The power supply is now re…
... voltages on every component. Every IC seems to have good power ... while, it seems IC5 (left RAM circuit, a 4067-10) gets ... -
Issue 1 32K Memory Upgrade neededHi folks, as the title suggest im looking for the original sinclair memory board to make it 48k from 16k. Any other form will do or even instructions…
... should be noted that the RAM select signal is 0V for ... the -3 IC and +5V for the -4 ... -
"Lost" 48K expansionToday I dug up my Speccy after more than 10yrs of inactivity. I bought it as a 16K in 1983, than I had expanded to 48K and never had problem. Until t…
... which consists of eight 4116 RAM chips, and upper memory, ... computer has by testing the RAM, and evidently, on ... of upper RAM) which indicates either upper RAM is not ... present at all, or it's faulty.< ... for upper memory - each RAM chip is attached to ... -
Testing RAM Chips After RemovalHi I am going to use Winstons Hot Air Gun method of removing the RAM chips from a 4S circuit board. I wish to check the RAM chips, I have a Logic Pr…
... I've found out about faulty M1 lines, I'm making ... to not need any working RAM at all (the board should ... the ROM and all the RAM - but not the ULA since ... -
Anybody fancy coding this?blah de blah de blah Please ignore, poting error.
... -world memory failures with 4116 RAM.
One thing to ... .).
In this final faulty 4116, the influence error is ... (this could be caused by faulty row/column address selection in ... -
Personal Gaming History in (very) Brief'79:PrinztronicMicro5500 --> '80:PlayedCoinOp(Space Invaders) --> '83:Spectrum(48K) --> '84:Spectrum+(kit) --> '86:Spectrum128 --> '88:AtariST --> '9…
... ones retrun as it was faulty.
December 1984 - Third Rubber ... Paid £75 for 4mb of RAM.
1994-2007 continually ... -
problem with sinclair zx 48 issue 6aHi all, I have the following problem when I turn on my sinclair without rom inserted. [url]http://217.79.64.145/sinclair/5.jpg[/url] when I turn o…
... open circuits from the new IC sockets - I missed a piece ... I'd replaced the 4116 RAM and it caused me no ... -
TIPP31 transistor questionYesterday I had the time to try and repair a 4S issue 48k spectrum I had. First of all I replaced all the electrolytic capacitors. The tr4 transistor…
... the power cirquit could be faulty ?(the Zener for example). I ... ?
Could it be a RAM chip that is ready to ... -
48K Speccy not workingHey, A few months ago (hope it´s not to late) I was loading a game into my speccy and from one moment to another it stopped working! I unplugge…
... /+5v supply at the 4116 RAM is a convenient place to ... .
Incidentally, on bad RAM, don't bet on flashing ... 't forget that the 4116 RAM is arranged such that there ... copyright message. All of the faulty 4116 chips in my collection ... -
Problems with TS2068sI bought 2 TS2068s, and this is what's happening: 1st computer: -The tv output doesn't work. The composite video output does* -The '7' key is dead.…
... ]If the Timex uses 4116 RAM, it probably has a little ... TC 2048 uses six 4416 ic's that only need 5 ... -
UlaI remplaced an ULA 6c001-6 by an ULA 6c001-7 chip on issue 3B board. It is "crucial" to remove R32 and adding the 2x NAND gates ??? or not ? Thanks.
... heat dissipation ;) .It's one IC RAM version and also has one ... -
UlaI remplaced an ULA 6c001-6 by an ULA 6c001-7 chip on issue 3B board. It is "crucial" to remove R32 and adding the 2x NAND gates ??? or not ? Thanks.
... heat dissipation ;) .It's one IC RAM version and also has one ... -
UlaI remplaced an ULA 6c001-6 by an ULA 6c001-7 chip on issue 3B board. It is "crucial" to remove R32 and adding the 2x NAND gates ??? or not ? Thanks.
... 's because of a faulty 16K expension RAM pack. The ZX81 randonly ... an decoupling capacitor inside the RAM expension pack and "miracle" no ... -
UlaI remplaced an ULA 6c001-6 by an ULA 6c001-7 chip on issue 3B board. It is "crucial" to remove R32 and adding the 2x NAND gates ??? or not ? Thanks.
... am after a 48K spectrum RAM chip: [B]TMS4532-4[/B ... are 64kx4, 4532s are half-faulty 64kx1s).
The only ... -
+2B ram chips?Hi all, I have got 2 Plus2B`s and 1 Plus2 gray case. Ok the one Plus2B don`t work, so I tried to see if I could pin down the problem. I changed the …
... of changing it. Test the RAM first, then the ROMs, ... if neither of these are faulty, it's a scrapper ... />
If it's RAM, and to be honest, I ... yourself, you could test the ram.....
The grey ... +2 uses 4164 RAM should you ever need to ...