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 Post subject: Re: Questions that do not deserve a thread
PostPosted: Sat Dec 12, 2020 12:28 am 



Joined: 25 Jan 2016
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vol.2 wrote:

Looking at that manual shows the sync goes through components in the Q board. (page 74-75) There are caps, diodes and transistor for each input. However, if you are experiencing sync issues on all inputs, then that probably points to a bigger issue. It's unlikely that a single bad component in the input board is going to ruin the sync for all inputs. (but not impossible if the sync circuit is being shorted out or something.

The sync goes through more than one IC. The main IC in the set, IC101, is the UPD78014FYCW-W23 and that would be part of the sync. I guess if that was bad it would screw things up. It's hard to say. The IC is not made anymore, but you may be able to get it through a sony part place. Probably cost a lot to find out if it's the issue.


Thanks man. I'll pull up a schematic and try and follow it with the starting points you gave me. I'll look up how to test the components and hopefully that will produce a culprit. I appreciate your input.


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 Post subject: Re: Questions that do not deserve a thread
PostPosted: Sat Dec 12, 2020 2:23 am 


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ajdesmarais wrote:
Thanks man.



NP. Also, clean the connector between Q board and A board very well with Deoxit. Spray it in the holes and insert remove insert remove many times. All of the sync signals travel over that connector.

Unfortunately, these things can be hard to figure out even for someone with the correct equipment. If it gets too hairy, prob best to have it repaired.


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 Post subject: Re: Questions that do not deserve a thread
PostPosted: Sat Dec 12, 2020 4:28 am 



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vol.2 wrote:
NP. Also, clean the connector between Q board and A board very well with Deoxit. Spray it in the holes and insert remove insert remove many times. All of the sync signals travel over that connector.

Unfortunately, these things can be hard to figure out even for someone with the correct equipment. If it gets too hairy, prob best to have it repaired.


Will do. I've been open to having some kind of professional take a look at it, because while I could probably eventually fix it by doing the random buy-and-replace tactic, the alternative is certainly more comfortable. Shame we're in the middle of the pandemic, but it'd also the only reason I've had time to try and fix it. Thanks!


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 Post subject: Re: Questions that do not deserve a thread
PostPosted: Mon Dec 14, 2020 1:07 am 


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Quote:
Impractical to test because it would depend on the individual monitor or TV. You would have to look at the schematic and evaluate the circuit and anything upstream from the input to determine the effect of 5V. That would mean pulling datasheets to look at absolute maximum ratings in addition to a holistic evaluation of the sync input in the system.


I agree it's impractical. Studying datasheets is the starting point. Lot of effort but would be desirable to find consumer CRTs that can accept either sync level.

Thanks Kez for the feedback and I needed some criticism! I want to be practical, not excessively thorough. Made me angry of all the resources and datasheets I had to buy a new computer and graphics card with versus what is out there for analog cables (and ADC processing on televisions).

1 - Impedance mismatching is an important point here. Just using an online calculator, matching 470 ohms to 75 results in dB loss of 3.2. That's the difference between Component quality and S-Video on video lines. The sync line handles losses much better but the reflected wave can crosstalk on video.

2 - I get what you're saying about not being proactive in search of a problem if everything looks good as is. Since I want to measure cable quality already from one make to another, chaining connectors to see how much noise is added isn't much more effort. Maybe help SCART coupler sales. I am impressed with RetroRGB science on controller input lag: https://www.retrorgb.com/controllerlag.html

With cables on hand, I need 7 connectors to go from SNES to DVI-A capture card. Could buy a SyncBaby for $65 to reduce to 3 connections but I have to guess if going deeper down the rabbit hole is worth it.

3 - Sure, a somewhat long 2 meter cable line is only 7-10 ns of delay. That's invisible to someone playing a video game. Just hypothetically, I'd predict the sync line trailing RGB lines by 1/2 the wavelength of 15 kHz vertical sync to black out the screen. That would take a delay of 133 µs (133k ns). The delay of the LM1881 sync separator, as I read it, is 65 µs. I just want to be as exact as I can. But this is too far, yeah. Maybe there are edges case where the small things matter, like RGB modding a system already known for sync issues (daty2k1's chart): https://shmups.system11.org/viewtopic.php?f=6&t=57929&start=180

4 - Good points. Too bad I don't have an interest in supergun measurements and fixes. I got the idea to test for out of spec levels when I read the last page of the manual for my PVM-L2: http://www.broadcaststore.com/pdf/model/784902/pvm-20l2.pdf
External Sync spec is:
Quote:
4.0 Vp-p ± 6 dB, sync negative, usable tri-level sync signal 0.6 Vp-p ± 6 dB

HD signals use the tri-level 0.6 level sync versus bi-level 0.3 for SD. You would know what dB means here but to explain for someone without a circuits background:
The ± 6 dB means an error margin (input tolerance) of ± 75% power, or ± 86% voltage at fixed impedance. Not enough for 0.3 Vp-p CSYNC to work on 4.0 Vp-p, yet it does.


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 Post subject: Re: Questions that do not deserve a thread
PostPosted: Fri Dec 18, 2020 2:00 am 


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I have a random question. I am trying to learn about electronics and modding consoles...

What farad capacitor does the PS1 and PS2 have on the chroma (C) signal. I could open them up, but I don't want to do that quite yet. Also, on the stock original NES (no mods), what farad capacitor does the composite video (V) line have?

Thanks.
Erik W.


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 Post subject: Re: Questions that do not deserve a thread
PostPosted: Sat Dec 19, 2020 12:46 am 


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This is a real random one, but it was always in the back of my mind when I had a Dreamcast & a Toro:

Back when the Toro was new, were many people here (or ANYWHERE) keen on making custom connectors for the Toro so it could be used with other consoles? Obviously the 31kHz switch would be rendered useless, but it seems like it could be a fun little day-project... getting 15kHz RGBS or RGBHV out of any of your consoles via the DE15 out connector, plus still having good ol' SCART on hand, heh.
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 Post subject: Re: Questions that do not deserve a thread
PostPosted: Sat Dec 19, 2020 10:09 am 



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kitty666cats wrote:
This is a real random one, but it was always in the back of my mind when I had a Dreamcast & a Toro:

Back when the Toro was new, were many people here (or ANYWHERE) keen on making custom connectors for the Toro so it could be used with other consoles? Obviously the 31kHz switch would be rendered useless, but it seems like it could be a fun little day-project... getting 15kHz RGBS or RGBHV out of any of your consoles via the DE15 out connector, plus still having good ol' SCART on hand, heh.
They even sold the connections themselves at one point. Then they realized they could make more money by selling full boxes instead of small upgrades, so they stopped. You can always make your own, but there's a reason my Toro is sitting in a box unused.


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 Post subject: Re: Questions that do not deserve a thread
PostPosted: Sat Dec 19, 2020 2:54 pm 


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erik343 wrote:
What farad capacitor...


It is unlikely that anyone is going to know this off the top of their head. They would have to look up the schematic.

Quote:
I am trying to learn about electronics and modding consoles...


Please don't think I'm being "mean" here, but this is an opportunity for you to actually do this. Go find schematics and figure it out. It's a perfect chance to start learning.


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 Post subject: Re: Questions that do not deserve a thread
PostPosted: Sun Dec 20, 2020 7:43 am 


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Hey y'all, just a quick question about my BVM. I have an A20F1A, and the upper and lower right hand corners have some slight discolouration, probably magnetic in nature, as whenever I spin it around it changes in intensity, as well as when I adjust the landing. Now, if I adjust things to remove the discolouration up top, it intensifies down the bottom, and the opposite occurs as well. Best I can do is get it kiiiind of balanced beteeen the two, but still with some slight discolouration. Anyone have any idea what the best way would be to possibly remove it altogether? Magnetic strips on the edge of the tube or something along those lines?


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 Post subject: Re: Questions that do not deserve a thread
PostPosted: Mon Dec 21, 2020 6:19 am 



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This is an opinion question, so any answer is correct. Tad bit of background, I've decided I like collecting (and playing of course) several different consoles and have them connected to my Sony Trinitron (which I would like to RGB mod).

Anyhow, I've come across and now own (in total) two Fat PS2's, one PS2 slim and an original PlayStation. I don't need to keep all of them, but what sounds like the best setup?:

  1. Keep the slim and the PS1. That way I have the PS1 for nostalgia reasons and the PS2 Slim won't take up very much more space?
  2. Keep just one Fat PS2 and sell the rest. That way I can add an HDD in the future if I so desire?
  3. Although on the other hand, my PS2 Slim is a 70000 model that could be modded (not easily) to accept an HDD or maybe even an IDE to Micro SD card adapter, perhaps leading to even more space savings?
  4. Or just keep a PS2 Fat and the original PS1 just because?

I just don't know what I really want to do with them yet. Maybe someone else knows of some advantages or disadvantages to one or the other. With a couple of Wii's I got I know what I want to do with those. I want to keep one of the Wii's that's newer even though it doesn't play Game Cube games because it has better video output, can be modded to output RGB and I want to get a Game Cube anyway so add a Game Player.

PS. (No pun intended). I also found a PS3 slim that won't play PS2 games for cheap so I went ahead and bought it. I'm not sure how that fits into the picture though since I never though I'd buy and own a PS3. But I don't know why I would get rid of it unless I could trade it for a console I'd be more interested in.

Maybe this is a sign I need to stop looking for cheap yard sale deals. I think I heard there's a pandemic, or something like that, going on right now.


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 Post subject: Re: Questions that do not deserve a thread
PostPosted: Mon Dec 21, 2020 11:43 am 


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ldeveraux wrote:
kitty666cats wrote:
This is a real random one, but it was always in the back of my mind when I had a Dreamcast & a Toro:

Back when the Toro was new, were many people here (or ANYWHERE) keen on making custom connectors for the Toro so it could be used with other consoles? Obviously the 31kHz switch would be rendered useless, but it seems like it could be a fun little day-project... getting 15kHz RGBS or RGBHV out of any of your consoles via the DE15 out connector, plus still having good ol' SCART on hand, heh.
They even sold the connections themselves at one point. Then they realized they could make more money by selling full boxes instead of small upgrades, so they stopped. You can always make your own, but there's a reason my Toro is sitting in a box unused.


Why’s that? Just opting for a straight-up VGA cable, have a GDEMU and patch everything for VGA?

I remember not being keen on the artificial scanlines, but did admire that it could be essentially a Sync Strike with the option of passthrough and either a sync cleaner or combiner. Unless my memory is off and it just passed whatever 15kHz RGB sync the connected console is standardized for on the SCART out...
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 Post subject: Re: Questions that do not deserve a thread
PostPosted: Tue Dec 22, 2020 3:59 am 



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Could it be possible to power the Scart version of the Retro Tink via the 5V line on the scart cable itself essentially powering it via the console???


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 Post subject: Re: Questions that do not deserve a thread
PostPosted: Tue Dec 22, 2020 1:58 pm 


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Issac Zachary wrote:
Could it be possible to power the Scart version of the Retro Tink via the 5V line on the scart cable itself essentially powering it via the console???


Nope, that is just a signalling pin with very low current. Not enough to power something like a Tink.


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 Post subject: Re: Questions that do not deserve a thread
PostPosted: Tue Dec 22, 2020 2:06 pm 



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I posted before, but looking for advice. I have 6 composite audio devices into a manual switch. I'm looking to automate with an automatic switch that actuates on signal. Only 1 device will be active at a time, so auto switching is the way to go. Anyone know one?


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 Post subject: Re: Questions that do not deserve a thread
PostPosted: Tue Dec 22, 2020 3:21 pm 


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ldeveraux wrote:
I have 6 composite audio devices into a manual switch. I'm looking to automate with an automatic switch that actuates on signal.


By "composite" I think you mean "RCA/phono," so I'm going to answer you based on that assumption. First off, what you're looking for is a function that is performed by 2 common devices in a signal chain. The most common approach is to use a preamplifier that has the number of inputs that you require. The second approach is to use a mixer. Preamps tend to have remote controls, giving you the actuation; mixers sometimes have remotes, but only the more expensive and complicated ones, and you would end up with a large device with lot's of controls. There are small, passive mixers which do not have a remote (I use one of those for one of my setups).

Another more common way that source switching is accomplished (especially in commercial installation) is with speaker source switches. This is at all times preferable because you lose less signal when it is already at a higher level. If you put switches and cables between a source and the amplifier, you will lose detail in the signal because it so low. This is especially an issue in commercial installation because cable runs tend to be much longer.

If you want the function you're looking for, you are going to have to think outside the box. The best I can think of is an AV switch with remote, which has both video and audio, and just use the audio part. Unfortunately, AV is almost dead in the consumer marketplace (for HDMI), so you may not find it new anymore. You can check ebay, etc and it should be cheap.

However, if it was me, I would probably take care of whatever function of switching you are trying to accomplish in a better way that maintains signal integrity.


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 Post subject: Re: Questions that do not deserve a thread
PostPosted: Tue Dec 22, 2020 4:56 pm 



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vol.2 wrote:
ldeveraux wrote:
I have 6 composite audio devices into a manual switch. I'm looking to automate with an automatic switch that actuates on signal.


By "composite" I think you mean "RCA/phono," so I'm going to answer you based on that assumption. First off, what you're looking for is a function that is performed by 2 common devices in a signal chain. The most common approach is to use a preamplifier that has the number of inputs that you require. The second approach is to use a mixer. Preamps tend to have remote controls, giving you the actuation; mixers sometimes have remotes, but only the more expensive and complicated ones, and you would end up with a large device with lot's of controls. There are small, passive mixers which do not have a remote (I use one of those for one of my setups).

Another more common way that source switching is accomplished (especially in commercial installation) is with speaker source switches. This is at all times preferable because you lose less signal when it is already at a higher level. If you put switches and cables between a source and the amplifier, you will lose detail in the signal because it so low. This is especially an issue in commercial installation because cable runs tend to be much longer.

If you want the function you're looking for, you are going to have to think outside the box. The best I can think of is an AV switch with remote, which has both video and audio, and just use the audio part. Unfortunately, AV is almost dead in the consumer marketplace (for HDMI), so you may not find it new anymore. You can check ebay, etc and it should be cheap.

However, if it was me, I would probably take care of whatever function of switching you are trying to accomplish in a better way that maintains signal integrity.


Thanks that's exactly what I was looking for! I did a bit more research and completely forgot about my mixer. I can get a powered, 8 input mixer for cheap enough so that should fit the bill. I've got to get all my inputs to 1/4" stereo into the mixer, but some simple adapters should work there. Thanks again!


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 Post subject: Re: Questions that do not deserve a thread
PostPosted: Thu Dec 24, 2020 5:51 am 


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Quote:
Should I be worried about all my old cartridges with battery backups having the batteries leak?


I saw one now-deleted thread on Reddit that had a damaged Super Mario All-Stars CR2032 with battery material all over the PCB board. I did find the explanation:

I’ve changed dozens of these batteries and I’ve never seen one of them do this before. Most of the time they just stop putting out enough voltage to keep the save file. I suspect something else was involved, like water.

So I think you have no leak concern like you do with expired AA or AAA.

----------

That said, My official SFC JP21 cable came in the mail but colors are so dark to make games unplayable: https://imgur.com/2Of8g7N
Reading other posts, most likely explanation is the capacitor on R, G or B died or doesn't exist. Just to be sure, official Nintendo RGB cables use 220 μF capacitors right? Multiout slot so narrow I'm not sure if I'm measuring G to G but I get 201-215 pF, which seems impossible.

I have cheap generic JP21 that works so I know my setup is correct.


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 Post subject: Re: Questions that do not deserve a thread
PostPosted: Thu Dec 24, 2020 9:42 am 


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NewSchoolBoxer wrote:
That said, My official SFC JP21 cable came in the mail but colors are so dark to make games unplayable: https://imgur.com/2Of8g7N
Reading other posts, most likely explanation is the capacitor on R, G or B died or doesn't exist. Just to be sure, official Nintendo RGB cables use 220 μF capacitors right? Multiout slot so narrow I'm not sure if I'm measuring G to G but I get 201-215 pF, which seems impossible.

I have cheap generic JP21 that works so I know my setup is correct.


I don't think a missing capacitor would do that. Are you sure your unofficial cable is actually JP21?


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 Post subject: Re: Questions that do not deserve a thread
PostPosted: Thu Dec 24, 2020 5:36 pm 


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Quote:
I don't think a missing capacitor would do that. Are you sure your unofficial cable is actually JP21?


Yes, since I bought wookieewin's Female RGB21 to 4 BNC breakout cable and it has the "RGP 21 ONLY" sticker on it.

Your comment was crucial because I decided to go back and look at the eBay pictures for the SHVC-010 cable. First two pics are what came in the mail, second two are from auction: https://imgur.com/a/pglTWSX

My cable is darker shade of grey. Maybe, MAYBE due to lighting difference. First eBay picture has all 20 pins and the second has the correct 14. Both cables have same E78671 AWM style 2933 VW-1/FUJI/E. W. C printing but unsure if that is datable to SFC era or not.

I found this thread about dark video from same cable. Last post on page has screenshots and first on next page by kamiboy states known leaky capacitor issue: https://shmups.system11.org/viewtopic.php?f=6&t=43256&start=2460

Between inconsistent auction pictures, dark video typical of dead capacitor and having actual working JP21 cable as comparison, I'll be good on disputing the charge. Wish I knew how to pop open the cable without breaking it though.


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 Post subject: Re: Questions that do not deserve a thread
PostPosted: Thu Dec 24, 2020 5:59 pm 


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I can't look at your images right now as imgur seems to be playing up (or my internet), but the picture you linked before didn't look like it was dark.. it looked like it had no colour at all. It looked to me like a luma signal with no colour information.


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 Post subject: Re: Questions that do not deserve a thread
PostPosted: Thu Dec 24, 2020 8:47 pm 


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NewSchoolBoxer wrote:
Wish I knew how to pop open the cable without breaking it though.


Should be able to unscrew the round stress relief part, then pry open the scart head on one side since it has little plastic pins. Don't know how standard that is but that's all the scart connectors I've personally seen.


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 Post subject: Re: Questions that do not deserve a thread
PostPosted: Fri Dec 25, 2020 3:50 am 



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NewSchoolBoxer wrote:
Quote:
I don't think a missing capacitor would do that. Are you sure your unofficial cable is actually JP21?


Yes, since I bought wookieewin's Female RGB21 to 4 BNC breakout cable and it has the "RGP 21 ONLY" sticker on it.


Never got around to opening it and checking the wiring, but the JP21 to BNC adapter cable I got from wookiewin years ago never worked. Had to get another one from a different seller (and that one eventually stopped working as well).

Quote:
Your comment was crucial because I decided to go back and look at the eBay pictures for the SHVC-010 cable. First two pics are what came in the mail, second two are from auction: https://imgur.com/a/pglTWSX

My cable is darker shade of grey. Maybe, MAYBE due to lighting difference. First eBay picture has all 20 pins and the second has the correct 14. Both cables have same E78671 AWM style 2933 VW-1/FUJI/E. W. C printing but unsure if that is datable to SFC era or not.

I found this thread about dark video from same cable. Last post on page has screenshots and first on next page by kamiboy states known leaky capacitor issue: https://shmups.system11.org/viewtopic.php?f=6&t=43256&start=2460

Between inconsistent auction pictures, dark video typical of dead capacitor and having actual working JP21 cable as comparison, I'll be good on disputing the charge. Wish I knew how to pop open the cable without breaking it though.


The capacitors in the official SFC JP21 cables should definitely be replaced according to a local cable maker I've bought from before, he sells cap kits with 6.3V 220μF capacitors: https://www.amazon.co.jp/P-001-%E3%82%B ... B004GBOYH4

Couldn't find info on opening the cable though.


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 Post subject: Re: Questions that do not deserve a thread
PostPosted: Fri Dec 25, 2020 5:03 am 


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Imgur not loading for me either. The cable actually worked this time, minus unacceptable horizontal bars on every screen. Can make out some yellow on the dark ring circle picture I took yesterday:
https://postimg.cc/gallery/jqp6tYy
I'd think leaking capacitor or very low quality parts of a counterfeit to blame.

Thanks bobrocks95! I was able to easily open the Sony JP21 cable (SCPH-1050) and verify 220 μF capacitors and a 75 ohm 5% tolerance resistor: https://postimg.cc/gallery/w6M5cZG

"Nintendo" I can unscrew about 1/8 a turn before it hard stops, like it has a latch to prevent being opened. Is not grey like it's supposed to be. With Sony correct grey confirming my lighting isn't to blame, dark cable color proves what I bought is a fake SHVC-010 and doesn't match seller's own photos.

So I'll dispute the transaction on counterfeit grounds to dodge seller bs about shipping damage or something. Could say is fake GameCube JP21 cable but I only know of the real thing existing in SCART form.


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 Post subject: Re: Questions that do not deserve a thread
PostPosted: Sat Jan 02, 2021 8:15 am 



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I'm verifying MAME romsets in ClrMamePro. When I download old archived .DAT's from Progettosnaps for a particular set why are there 7 different .DAT files in the archive I download? Ending in __U1.dat, __U2.dat, __U3.dat etc.?

I've been using the first one but I don't know if that's correct and would like to know what the others are for (all but the last one are the same size and seem to have identical content at first glance...).

**EDIT, found some logs online and these seem (might be) incremental updates to MAME? And by the change logs some seem to be pretty huge changes (like one was overall memory management type stuff) – I never knew they did these - always thought they ONLY got wrapped into the next full release.... so this adds to the confusion. If a certain emulator says it can ONLY use Mame 2003 0.78 (like Raspberry Pi 4/RetroPie) does it mean to use 0.78, 0.78U1, U2, U3, U4 etc etc? The last U6 for instance isn't even a full list! It's like 5 megs vs the 9 of all the others!


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 Post subject: Re: Questions that do not deserve a thread
PostPosted: Tue Jan 05, 2021 10:38 pm 


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Anyone know any specific refurbish tips for a Neo Geo CD stick (the bean shaped one)? I'd like to grease the stick since it's pretty stiff and doesn't hit directions smoothly, unless replacing the spring or microswitches would better solve the problem. Wouldn't mind a ball top or an octagonal gate either if those are easily replaceable.

I have some white lithium grease and some grease that came with my mechanical keyboard if either are appropriate?


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 Post subject: Re: Questions that do not deserve a thread
PostPosted: Tue Jan 05, 2021 10:56 pm 



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Have a question regarding TTL sync. As I understand it TTL is 5vpp, however, a couple PVM's of mine (PVM-3230, PVM-8045Q) say that they support TTL, but at 4vpp. So my question is, would TTL coming from a Crosspoint (because as I also understand, that is what all Crosspoints output) potentially damage these displays? Just from those numbers the answer would seem to be yes, but I feel like there's prob more to the story here that is above my pay grade.


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 Post subject: Re: Questions that do not deserve a thread
PostPosted: Wed Jan 06, 2021 4:28 am 


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jamon1567 wrote:
As I understand it TTL is 5vpp, however, a couple PVM's of mine (PVM-3230, PVM-8045Q) say that they support TTL, but at 4vpp.



TTL 5V pktpk is the standard but not all devices adhere to it. The 3230 supports IBM TTL input from a CGA card, it can handle TTL and I wouldn't hesitate personally to do so. I've never looked into the other monitor.


What source do you have that puts the 3230 at 4Vpktpk? I think I've read all the technical documents released on that monitor and I've never seen mention of a specific voltage for the digital inputs, just that it's TTL.


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 Post subject: Re: Questions that do not deserve a thread
PostPosted: Wed Jan 06, 2021 6:05 am 



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vol.2 wrote:
What source do you have that puts the 3230 at 4Vpktpk? I think I've read all the technical documents released on that monitor and I've never seen mention of a specific voltage for the digital inputs, just that it's TTL.

The higher voltage one is always the sync, and for RGBS it's external sync, and the manual does say 4.0vpp for external sync on page 29:

External sync input:
BNC connector
4.0 Vp-p ±6 dB, negative
automatic 75-ohm termination

I have this monitor and I've never worried about it though - it's a PVM meant for standard sync signals which 5 would be. I also don't know what the +/- variance means when it's listed in "dB".


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 Post subject: Re: Questions that do not deserve a thread
PostPosted: Wed Jan 06, 2021 2:29 pm 


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vol.2 wrote:
jamon1567 wrote:
As I understand it TTL is 5vpp, however, a couple PVM's of mine (PVM-3230, PVM-8045Q) say that they support TTL, but at 4vpp.



TTL 5V pktpk is the standard but not all devices adhere to it. The 3230 supports IBM TTL input from a CGA card, it can handle TTL and I wouldn't hesitate personally to do so. I've never looked into the other monitor.


What source do you have that puts the 3230 at 4Vpktpk? I think I've read all the technical documents released on that monitor and I've never seen mention of a specific voltage for the digital inputs, just that it's TTL.

I don't actually own an IBM CGA, but my IBM EGA outputs sync at 3.3V LVTTL levels FWIW

4V + 6dB is about 8 volts, 5V is perfectly fine


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 Post subject: Re: Questions that do not deserve a thread
PostPosted: Wed Jan 06, 2021 2:34 pm 



Joined: 09 Dec 2016
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vol.2 wrote:
jamon1567 wrote:
As I understand it TTL is 5vpp, however, a couple PVM's of mine (PVM-3230, PVM-8045Q) say that they support TTL, but at 4vpp.



TTL 5V pktpk is the standard but not all devices adhere to it. The 3230 supports IBM TTL input from a CGA card, it can handle TTL and I wouldn't hesitate personally to do so. I've never looked into the other monitor.


What source do you have that puts the 3230 at 4Vpktpk? I think I've read all the technical documents released on that monitor and I've never seen mention of a specific voltage for the digital inputs, just that it's TTL.


As Dochartaigh said, I pulled that information from the manual. I'm fairly certain there are other PVM's out there that are listed with the same specs as well. I've never heard of any issues, and I couldn't imagine that these monitors wouldn't support a broadcast standard, however 4 obviously is not 5, so it is a bit concerning, especially when you're talking about rare monitors like a 3230.


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