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Some problems with 2 ZX Specturm board'sHi, last week i got some ZX Spectrum stuff. Also 2 ZX Spectrum 48K's, one in the orginal case the anoter one in a DK'tronixs case. Both have problem'…
... 9).
Usually replacing TR4 (ZTX650) with a ZTX651/2 ... ) that is usually measured when TR4 is blown.
3 ... spot-on, which means that TR4-TR5 circuitry is working somehow, otherwise ... -
Using a Euro Sinclair PSU in UKI've got a EURO1400 PSU with a Euro plug. Am I right in thinking I can just cut the pug off and change it to a UK plug, and it will work fine? The on…
... which caused
the internal TR4/TR5 circuit to stop working. The ... -
IF1bis StabilityI just thought I would start a different thread relating to the IF1bis, and leave the copyrighters to it elsewhere...:-P I've had mine for a few mon…
... caused by the Spectrum?s DC-DC converter, until users started complaining. I ... -
+2 Grey video issueSo far ive replaced TR4, TR5 (and correctly orientated them) and seperated the audio from the video, still I have this; [youtube]mZZWOXRs_Zk[/youtube…
Nope, remember that TR4/TR5 on the grey +2 are ... perform very different functionality to TR4/TR5 in the 48K models :) (TR8 ... be used to replace both TR4 and TR5, I think the collector ... -
+2 Grey video issueSo far ive replaced TR4, TR5 (and correctly orientated them) and seperated the audio from the video, still I have this; [youtube]mZZWOXRs_Zk[/youtube…
... AMSTRAD has the silkscreen for TR4, TR5 and TR7 (all type 2N3904 ... .1 has the silkscreen for TR4, TR5 and TR7 printed correctly. So ... -
+2 Grey video issueSo far ive replaced TR4, TR5 (and correctly orientated them) and seperated the audio from the video, still I have this; [youtube]mZZWOXRs_Zk[/youtube…
For a[B] Z70500 ISS3[/B] board, fit replacement BC547/BC548/BC549 transistors exactly as per the silkscreen for TR4, TR5 and TR7 positions.
[I][B]Mark[/B][/I] -
+2 Grey video issueSo far ive replaced TR4, TR5 (and correctly orientated them) and seperated the audio from the video, still I have this; [youtube]mZZWOXRs_Zk[/youtube…
... the two "anchors"
8. TR4, TR5 and disconnected the audio from ... -
PSU Overvoltage?Going through a pile of 48k PSU's today, rewiring and fitting new plugs, testing each one as I go I came across one that outputs 14.85v, usually im g…
... load which caused the internal TR4/TR5 circuit to stop working. The ... -
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 …
... next.[/QUOTE]
TR4 & TR5 will be in working order ... -
TR4 or TR5?My issue two gives horizontal bars on bootup. Flicking reset takes it to copyright screen though. I measured voltages and got 4,9V, 11,99V and -4,3V.…
I'll second Mark's suggestion - I've seen boards producing out of tolerance -5V, capacitor replacement will sort this out.
In my experience TR4/TR5 are either 100% alive or 100% dead :)
B -
TR4 or TR5?My issue two gives horizontal bars on bootup. Flicking reset takes it to copyright screen though. I measured voltages and got 4,9V, 11,99V and -4,3V.…
A tally on the number of successful builds of the Harlequin[SIZE=4][COLOR=Green][U][B]A tally on the number of successful builds of the Harlequin.[/B][/U][/COLOR][/SIZE] Please post your successes below :-) …
... This is necessary to prevent DC offset at sync line of ... and to enable a DC path for the sync ... of using a CGA-VGA converter or any SCART using ... device with no DC path at sync line.< ... +12V line. An additional DC-DC converter can solve the problem.
Harlequin clone...PCB manufactured!Using Chris Smith's detailed schematics and project notes from the Harlequin... a Speccy fan in the United States by the name of Don (Superfo) has de…
Harlequin - usefull mods and addsHello, I start here a thread regarding mods and adds for the Harlequin. It was found: * that the Sinclair Interface 1 does not fully work at the Ha…
... with the labelling of your DC/DC converter circuit.
The -5V line ...Harlequin - usefull mods and addsHello, I start here a thread regarding mods and adds for the Harlequin. It was found: * that the Sinclair Interface 1 does not fully work at the Ha…
... with the labelling of your DC/DC converter circuit.
The -5V line ...Harlequin - usefull mods and addsHello, I start here a thread regarding mods and adds for the Harlequin. It was found: * that the Sinclair Interface 1 does not fully work at the Ha…
... ) what is provided by this DC-DC converter?
Note for readers ...Harlequin - usefull mods and addsHello, I start here a thread regarding mods and adds for the Harlequin. It was found: * that the Sinclair Interface 1 does not fully work at the Ha…
... with the labelling of your DC/DC converter circuit.
The -5V line ... the -12V output from the DC/DC converter as "-5V ==> B20" and ...Fixing my old ZX Spectrum 48K issue 4AHi Guys, I trying to fix my old Spectrum 48K. Looks like my dad used a wrong power supply as the ULA had a bit missing and so did the 7805. So I rep…
... , reinstall a new/known good TR4/TR5 but [B]do not power ... culprit of a continually blowing TR4 in your case is a ...Fixing my old ZX Spectrum 48K issue 4AHi Guys, I trying to fix my old Spectrum 48K. Looks like my dad used a wrong power supply as the ULA had a bit missing and so did the 7805. So I rep…
... , reinstall a new/known good TR4/TR5 but [B]do not power ... culprit of a continually blowing TR4 in your case is a ...AAAARRRRR DIV-MMC ENJOY againIve recently been posting trying to get to the bottom of problems with my +48 not working with this rechid addon.Now ive finaly worked out theres not…
... this creates.
Regarding TR4/TR5, they are the same components ...AAAARRRRR DIV-MMC ENJOY againIve recently been posting trying to get to the bottom of problems with my +48 not working with this rechid addon.Now ive finaly worked out theres not…
... components,will they be labeled TR4 TR5 or can i just use ...Toastrack ULA QuestionDid any of the toastracks have the +128 grey ula with Amstrad printed on them?
Thats why i was asking was thinking about spares but it could have same problem as mine at the moment. Do you think TR4 TR5?(THE ONE ON EBAY)ZX Spectrum 48K AV IssueOK so I dugout my old 48K Speccy today and decided to AV mod it. I did the mod (pretty easy) but the picture I am getting is this. [url=http://posti…
Really?
Ok I will change two transistors at TR4 & TR5 then try it again. Then start removing the ram chips I guess.ZX Spectrum 48K AV IssueOK so I dugout my old 48K Speccy today and decided to AV mod it. I did the mod (pretty easy) but the picture I am getting is this. [url=http://posti…
... get the electrolytic capacitors and TR4/TR5 changed you should have voltages ...ZX Spectrum 48K AV IssueOK so I dugout my old 48K Speccy today and decided to AV mod it. I did the mod (pretty easy) but the picture I am getting is this. [url=http://posti…
... fry the lower ram if TR4/TR5 blow up.
If ...ZX Spectrum 48K Issue 3, loss of -5V rail.Hi all, I've googled this problem and poured over the electrical diagrams for the circuitry concerning the power supplies and I believe I know what …
... highly recommended, as failure of TR4/TR5 will be a much more ...ZX Spectrum 48K Issue 3, loss of -5V rail.Hi all, I've googled this problem and poured over the electrical diagrams for the circuitry concerning the power supplies and I believe I know what …
... components that could die are TR4/TR5 and there's nothing left ...Youtube vids of US guy converting speccy into handheldDidn't see it posted here but thought it was a pretty interesting project. Part 1 and 2 here, more to follow. [youtube]6GcwcyL9LgM[/youtube] [you…
Well, I would use a DC-DC converter, as used on industrial boards ... ;Ntk=gensearch&Ntt=Voltage+converter+through+hole+PCB&Ntx ... .com/murata-power-solutions/cme0512sc/dc-dc-conv-iso-pol-1o-p ...'Interesting' Issue 2 modSo I've been lurking on this forum for a while and I've got to the point where I want to see if I can repair a speccy.. so I bought me a 'broken' one…
Missing TR4/TR5 too. Looks like it was modded to take an external ATX like supply providing +5v/-5v/+12v directly to the required rails.
BFaulty 48+ Help NeededHi, This is what I get when I plug in the spectrum, this is tuned in. Vid shows a reset. Any ideas, or pointers on the first thing to check. Keyboa…
No colour would suggest that TR4/TR5 have failed. A supply rail ...
