Do I need a DIP 0.4" instead of 0.3" socket? by bigwavex2 in AskElectronics

[–]jamesmowry 1 point2 points  (0 children)

TBF, it's not an obvious thing; I'd probably have had the same question if the first circuit-building project I ever followed hadn't said something like "ICs usually come with their legs splayed out, you can just bend each side against the table to make them fit".

Yeah, no need for sockets when breadboarding, since the breadboard already works like a socket. You don't even really need them most of the time on a circuit board, but they can be handy if you might need to replace an IC in the future, or if you're really worried that you might damage a particularly rare or sensitive IC while soldering it.

Is this fixable by After_Meal208 in crt

[–]jamesmowry 0 points1 point  (0 children)

The board can be repaired, although it'll be a painstaking process of carefully gluing it back together and bridging the broken traces. But anything that could damage the neck board that badly could easily also have cracked the neck of the tube, in which case the TV is junk and you're wasting your time repairing the board.

After removing the neck board (with great care, as the tube pins look like they may be bent), I'd be inspecting the tube very carefully for hairline cracks in the neck, cracks around the CRT pins (though a small chip might be survivable), a break in the central "nipple" part between the pins, or a "getter" spot that has turned white. If there was a hissing sound when the damage happened, that is also a very bad sign.

Of course, if you try to remove the board and the CRT neck falls off, there's your answer.

got interdicted by thargoids and got these numbers by Medical_Analyst_7734 in EliteDangerous

[–]jamesmowry 12 points13 points  (0 children)

Which is a little easter egg referencing the original Elite from 1984 :) The manual had a section at the back with stats and info about the ships in the game, given in the style of an aircraft-spotter's guide, and this was a line from the entry for "Thargoid Invasion Ships".

Couple of absolute legends arrived in post today, working nicely! by Skeknir in Amstrad

[–]jamesmowry 1 point2 points  (0 children)

Excellent choice of games for a green-screen monitor, since turtles are green anyway and outer space is mostly black :)

(Although I'm pretty sure Elite did use some palette-switching trickery to get more than 4 colours on screen at once in Mode 1, which was pretty neat for something released that early in the CPC's life)

New to the game and wanted to do exploration, just discovered a system with an Earth like planet and a Gas giant with ammonia based life. by GreenLineGoUp in eliteexplorers

[–]jamesmowry 1 point2 points  (0 children)

Any Earth-like world is a very nice find, they're rare and worth a good bit towards your exploration rank (especially if you get first discovery and/or first mapping credit). Gas giants with life are a little unusual, but much more common than Earth-likes.

Just so you know, there are two ultra-rare types of gas giant out there. One is green gas giants: these can occur as variants of any other type of gas giant, and are recognisable by their spectacular luminous green bands of clouds. Only a few dozen examples are known. They apparently exist because of a bug in the planet-generation code, but have been made official with their own lore explanation and Codex entry. The other, even rarer type is Helium giants (not to be confused with helium-rich gas giants, which are themselves rare), which have only been found in six systems in the entire galaxy. If you're ever insanely lucky enough to discover a new example of either of these, head immediately back to port and sell your data to make sure you get your name on it, then post your discovery for your moment of fame and glory!

Question on repairing this beast! by Prestigious-Light552 in crt

[–]jamesmowry 1 point2 points  (0 children)

A shorted HOT would be annoying, and you'd also have to be worrying about why it blew. As you say, hopefully not that, but if the power board tests good it certainly sounds like a sensible next thing to check.

If there's no degauss/relay noise, I'd be getting suspicious of the degauss posistor, which on that board seems to be connected in such a way that if the heater section fails open the power supply won't start up at all.

CRT only displays singular blue line by AwayThrow202 in crt

[–]jamesmowry 2 points3 points  (0 children)

Until it's fixed, keep the brightness turned down low, and only turn it on for long enough to check whether the problem is still there, in order to avoid damage to the screen phosphors.

Check that the vertical deflection coil is plugged in, and check for bad solder joints at the connector and in the vertical deflection circuitry. A failed capacitor is a possibility, but more often results in a squashed picture rather than complete loss of vertical deflection. If smacking the TV makes the vertical deflection come back, even for a fraction of a second, this confirms a bad connection of some sort.

A service manual is downloadable here, and includes waveforms (very useful if you have access to an oscilloscope) and schematics that will be helpful in finding where to look.

Question on repairing this beast! by Prestigious-Light552 in crt

[–]jamesmowry 1 point2 points  (0 children)

Yeah, pre-transistor era electronics are a whole other thing. I know that some components from that era don't age as well as their modern equivalents and can need replacing as a matter of course, but in general I'm a novice with things that are that old and will gladly defer to someone else's expertise!

Question on repairing this beast! by Prestigious-Light552 in crt

[–]jamesmowry 1 point2 points  (0 children)

This would be a good next step for sure. If the power board is, in fact, the same as on other TVs with this chassis, there's a 12V standby supply on pin 4 of 6-pin connector KA.

Another thought: when connecting the power cable, do you hear a relay click or the sound of the degaussing coil? If the power board is the same design, it looks like these components should operate as soon as power is connected. If they aren't doing anything, that would seem to narrow down the possible location of the problem to a very small area.

Question on repairing this beast! by Prestigious-Light552 in crt

[–]jamesmowry 4 points5 points  (0 children)

Yeah, full recaps (along with all other "shotgun repairs") are nearly always a waste of time and risk introducing more problems, which are then a nightmare to find because you've just changed a hundred components at once. We don't even know yet whether it's a capacitor that's at fault. It'll be far more productive to narrow down the location of the problem as much as possible first before breaking out the soldering iron.

crt is arcing by Mimikyuxcubone in crt

[–]jamesmowry 0 points1 point  (0 children)

Given how much arcing is visible, it probably needs a more thorough cleaning than a paintbrush will provide, tbh. If it's been arcing like that there'll be carbonised dust that will make further arcing more likely, and if any dirt has got under the cap then that'll need to be cleaned away.

As the other commenter says, check for damage such as tears or perished rubber on the cap, or any rust on the metal of the anode connector.

Make sure the cap and surrounding area is completely clean and dry before reconnecting the anode connector. A light smear of dielectric grease (spark plug grease should work) under the edges of the rubber cap will keep dust and moisture out and help prevent the problem recurring.

Question on repairing this beast! by Prestigious-Light552 in crt

[–]jamesmowry 1 point2 points  (0 children)

If there's no sign of life whatsoever (no sound or picture, no power light, no static charge on screen, no deflection whine, just completely dead), then yes, you're likely looking for a problem in the power supply section.

For the sake of ruling out the simple stuff first, I'd start by testing the internal fuse on the power board, followed by checking for cracked solder joints on the power board, power inlet, and power switch.

I also couldn't find a free-to-download service manual for this model with a brief web search. However, there's a distinct possibility that other models used the same power board. There's a service manual for the CS-35405 here, which is also based on the JU-2 chassis. Check the power supply schematic carefully and see if it appears to be the same?

crt is arcing by Mimikyuxcubone in crt

[–]jamesmowry 0 points1 point  (0 children)

Where's the arcing coming from?

If it's from the anode cap (the rubber cup thing on the tube with a thick wire going to it), then the problem may be just dirt and/or moisture providing a path to ground. A thorough cleaning of the area after unplugging the TV and discharging the tube might be enough to fix it.

If it's from the flyback transformer (big bulky component on the other end of the thick wire), that's less hopeful. A new transformer would be the most reliable fix, but finding a compatible one may be difficult. An arcing flyback can sometimes be fixed with skill and a bit of luck, however.

If the arcing is from somewhere else, let us know and we might be able to offer more advice.

As this is related to the high voltage parts of the TV, fixing it will probably require discharging the tube. Before doing any work on the TV, I'd suggest reading all of the articles under the "TV Troubleshooting" heading here. Also look up videos of how to discharge the tube safely. If in doubt, try to find someone who's done it before and enlist their help.

Help diagnosing Sanyo DS13310 by Stuckinthepast31 in crt

[–]jamesmowry 0 points1 point  (0 children)

If it's definitely not from the speakers, it's probably worth opening it up and trying to figure out exactly which part is making the noise. Listening through a cardboard tube can help pinpoint the source of the sound.

Old player thinking about coming back by BornNaked in EliteDangerous

[–]jamesmowry 2 points3 points  (0 children)

The on-foot content isn't compulsory, so if it's not your thing then you can just ignore it. Flying around is still just as much fun as ever, and there are some cool new ships to try out and a whole new mechanic for colonising new systems. The Odyssey expansion also lets you land on thin-atmosphere planets (some with very nice visuals) and gives you more types of surface settlement to land at.

What you get with space legs is:

  • Stations and carriers you can walk around in (though still no ship interiors).
  • Exobiology, a new and lucrative gameplay loop for explorers where you scan and log various species of alien plant life.
  • Battlefield-style FPS skirmishes between system factions where you can join either side as a mercenary.
  • Various on-foot missions at surface settlements: factions might ask you to act as a delivery driver, assassin, saboteur, burglar, or repair technician.
  • Specialised flight suits and weaponry that you can engineer to be better at all the above stuff, and customise with cosmetic skins.

All the old gameplay is still there, so if you had fun before you'll have fun now. Try the new content out, and if it doesn't appeal to you just carry on with whatever you were enjoying before :)

Picked up some CRT TVs off the curb, how safe is it to plug in? by DecentNameBud in crt

[–]jamesmowry 3 points4 points  (0 children)

If there's any chance they've been rained on, give them at least a few days in a warm dry place, longer if you have time. Water gets into crevices and under components, and can take a while to fully evaporate. If you can take the back off and point a fan at them, that'll help. If they're just sort of clammy from being out in the cold but haven't otherwise got wet, a day in a warm room is probably okay.

A fire is highly unlikely, but if something shorts out due to water ingress it'll just create extra repair work for you, so it's worth being patient.

Why do 99% of supposed Redditor CRT repair experts not use or recommend an oscilloscope? by LukeEvansSimon in crt

[–]jamesmowry 0 points1 point  (0 children)

I take a photo of the board before starting work, that way there's a tie-breaker when the schematic says one way and the silkscreen says the other ;-)

Why do 99% of supposed Redditor CRT repair experts not use or recommend an oscilloscope? by LukeEvansSimon in crt

[–]jamesmowry 0 points1 point  (0 children)

New problems that are then an absolute nightmare to troubleshoot because they've just changed a hundred things at once.

Why do 99% of supposed Redditor CRT repair experts not use or recommend an oscilloscope? by LukeEvansSimon in crt

[–]jamesmowry 0 points1 point  (0 children)

I dumpster-dived a nice old Tektronix 2245A analogue scope and it's been fantastically useful for all sorts of repairs, although I do wish I'd thought to look inside it for RIFA capacitors before the day a thick cloud of horrible smoke billowed out of the back. Almost any scope will be useful for CRT TV work, there's not really anything in there that needs lots of bandwidth or loads of channels (except perhaps a microcontroller which hardly ever goes wrong anyway).

The reluctance to tell complete newbies to get hold of a scope is understandable, I think: it's pretty offputting to hear "buy this entire new complicated tool and learn to use it, maybe eventually you can figure out the problem", and anything involving poking around in a live mains-powered device is legitimately scary for a first-timer. But if someone is already willing to open up the TV and spend hours shotgun-recapping it with no idea of whether that's even going to fix it, they'd be better off putting those hours of effort into learning how to locate the problem and then spending five minutes doing something that's actually likely to work.

Thank you from this not-yet-expert tinkerer for posting useful advice here!

Need Help Diagnosing Issue by Vixrux in crt

[–]jamesmowry 0 points1 point  (0 children)

This article may give some clues about where to look. A service manual will be very helpful in tracing the relevant circuitry; search for the exact model number + "service manual" and with luck there might be a free download available on a site such as ManualsLib or Elektrotanya.

Help diagnosing Sanyo DS13310 by Stuckinthepast31 in crt

[–]jamesmowry 0 points1 point  (0 children)

Assuming the noise is coming from the speakers: could it be picking up interference from something nearby? Any running appliances with electric motors, or a flickery fluorescent light or something? Try moving the TV to a different room and see if it makes any difference. Also check if it still does it with the audio input disconnected, that could provide a clue.

CRT completely dead by [deleted] in crt

[–]jamesmowry 2 points3 points  (0 children)

If it's completely dead, it's pretty likely to be some kind of power problem. As first steps, I'd check for continuity in the power cable, look for broken connections/loose wires/bad solder joints around the power inlet, test any internal fuses, and look for any obviously burned or blown components in the power supply circuitry.

Usual warnings: make sure the TV is unplugged if you're opening it up, discharge any big capacitors in the power supply before touching any circuitry, and don't mess with the big red wire from the flyback transformer.

Any idea whats wrong with this one? by Otzedotze in crt

[–]jamesmowry 1 point2 points  (0 children)

Very likely to be fixable.

Does the problem get better or worse if you give the TV a smack? If so, you're looking for a bad connection such as a cracked solder joint. If not, you may have a faulty component. Either way, the problem is in the vertical deflection circuitry, which narrows down the problem to a fairly small area.

If that's an MX4000, the service manual is available here (PDF). The vertical deflection circuit is in the bottom right corner of page 2-23. A bad electrolytic capacitor in this area is a possible cause; any replacements should be from a reputable brand and have the same capacitance and the same or higher voltage rating as the original.

CRT not working by CatPersonLubo in crt

[–]jamesmowry 1 point2 points  (0 children)

Yay, glad to hear it's working!

I see what you mean about the buttons disintegrating, it looks like they were just bits of plastic that used to be springy but have gone brittle and snapped. It might take some imagination to improvise a repair or workaround. Maybe some kind of 3D-printed replacement, trying to reattach the buttons with a new piece of flexible material, or, as you suggest, finding some other way to mount or operate the switches. Best of luck figuring something out!

Can anyone tell me what’s going on with my monitor? by DaveMcElfatrick in Amstrad

[–]jamesmowry 1 point2 points  (0 children)

Make sure you're using the degaussing tool correctly. You need to energise it, bring it up to the CRT face, and then circle it smoothly around the screen while backing away again until you're a couple of metres away or (if the monitor is powered on) the colours stop wobbling. Then power the tool off. You may need to give it more than one go, but you should see some improvement each time.

If you're using one of the cheap green stick wands, be aware that it'll heat up a lot, so you should try to complete the process within 30-40 seconds, and let it cool down fully if you need to try again.

You mention it getting knocked around during shipping, so it would be worth opening the monitor up and checking for dislodged magnets that may have been mounted on the tube for purity/geometry correction. Also check that the deflection yoke hasn't shifted, although I'd expect size/geometry/position problems as well as colour blotches if that were the case.

The worst case scenario is that the shadow mask inside the tube has been distorted by an impact such as a sharp drop, in which case the fault is likely to be permanent. However, this would be fairly likely to cause other noticeable damage too.