monitor connection question

[tighecg]

hi guys, I'm new to the scene around here and I have a question about monitors. I'm thinking about picking up a BVM on ebay, and I was thinking about soldering a cable directly to the boards of various systems and terminating them with BNCs. Then just connecting straight to the monitor. My idea is that reducing the number of physical connections would help ensure signal quality. Is this a bad idea? Overkill? any issues I'm overlooking?

[BazookaBen]

I don't like the idea of modifying the shells of old consoles, but if you insist, the better option would be to put a HD-15 (aka VGA) female output + 2 RCA for audio. Then you can use a VGA>BNC cable to hook up video. That way you will save space on the back of your console. That's how the Analogue NT will be set up

I just made my own short cable that terminates in a VGA connector from old RF adapters and A/V cables, so I would have the convenience of VGA while leaving my consoles intact.

[tighecg]

ben, I would agree with you on modifying shells. I would never do it to a system that I did not have multiples of. But lets take the Genesis for an example. First off I have quite a few of them, a really nice non tmss collection piece I would never mod inside or out. I also have a really crappy one that I practice modding on, as well as a few more. If I remove the RF switch or the a/v jack I can run the cable out of that hole with a grommet, or cord grip to stabilize it. No mods to the shell, and I can always put those pieces back in. the VGA connector would add one more physical connection, and another point of failure to the set up. My question is will connecting straight to the board improve the signal quality, degrade it, or no effect? I'm not worried about the time or effort for this mod, I enjoy doing it, as I'm sure most here do. I have been a gamer all my life, and I am an industrial maintenance electrician. I have the skills to do the mod, but no experience with these particular applications. I have never worried about things like signal quality in my job. I know the parts, and I'm not ashamed to admit that I don't know the theory here. I mean no disrespect, and I whole heartedly agree with you on shell modding of systems in good shape.

[tighecg]

also I would use the headphone jack for sound

[mvsfan]

Non Tmss Genesis' really dont need any mods but the capacitors in them are usually bulging by now. I havent run across any leaking yet but most of them were close to leaking.

Sound quality also goes down on them because of It. if its not done i would replace them if any are starting to bulge. even a pristine one.

Ive also run across Genesis power supplies with caps that Are leaking. It affects video quality a lot.

Nes consoles though, ive never run across one with bad caps yet although i usually replace them anyway since its relatively easy especially on a toploader. they only have 5 caps.

The Genesis has close to 60 caps.

[ApolloBoy]

I don't like the idea of modifying the shells of old consoles, but if you insist, the better option would be to put a HD-15 (aka VGA) female output + 2 RCA for audio.

An even better idea would be to make a little breakout cable, since making a hole for a VGA connector is a pain in the ass. You could also just use a panel-mount 8-pin mini-DIN since it can accommodate pretty everything you need for RGB and audio. Then you can make one cable that you can use across multiple consoles.

[BazookaBen]

8-pin mini DIN's are still pretty easy to find? Easy to find cables that go 8-pin DIN to BNC?

[ApolloBoy]

8-pin mini DIN's are still pretty easy to find? Easy to find cables that go 8-pin DIN to BNC?

The connectors are widespread and making a cable isn't too hard.

[BazookaBen]

I need to learn how to make proper cables. Right now, my custom cables are just very short. Like 10 or 15 cm to some standard connection. Like Genesis 9-pin to VGA + 2 RCA. Then I just use standard cables to get to the actual monitor + stereo. And these short cables don't have any jacket, stress-relief, or shielding around the individual component wires. So I have to be pretty careful disconnecting and hooking them up because they can definitely be broken. If I were to yank hard by the wires I would definitely break it and have to resolder or something.

Let me know if you have any good tutorials on making some sturdy DIY cables.

[tighecg]

ok, all great information and suggestions. Does anybody have any experience with soldering cables directly to the board? thoughts or theories about doing this?

[ApolloBoy]

Does anybody have any experience with soldering cables directly to the board? thoughts or theories about doing this?

Don't do it.

[tighecg]

any particular reason why?

[mvsfan]

Yeah. what if your system just stops working and you need a new one? then you have to do it all over again.

think it cant happen? snes's have a weird problem where some of them just stop working one day. The power light will come on but they just give a black screen. People dont seem to know why they do it. I have a stack of them like that.

using the snes multiout is the way to go.

if you want few connections i think the best thing would be to make a console cable with a multiout plug that has 4 bncs on the other end.

i really dont understand though why people make their own cables, when good cables only cost $20.00 -30.00 and the parts cost about that plus my time. but to each his own.

Retro console accessories cables are Great. Ive had no problems with them whatsoever.

Most of my problems when i first started RGB was because of CHEAPLY built scart Splitters and switches.

[ApolloBoy]

i really dont understand though why people make their own cables, when good cables only cost $20.00 -30.00 and the parts cost about that plus my time. but to each his own.

Because some people have different needs for their setup and maybe want to know exactly what goes into their cable? It's really obvious if you think about it.

[mvsfan]

fair enough. custom setups do require custom made cables. if its not readily available i will make my own too.

[tighecg]

are there any performance related advantages or disadvantages doing this? connecting to the board?

[BazookaBen]

are there any performance related advantages or disadvantages doing this? connecting to the board?

People do it all the time, so I'd say no. I've never done it myself, but I've never seen negative reports from people that do this. I mean, you're an electrician, don't the electrons just move in the direction of wherever a grounded sink is available? Like, if you just connect to where the signals normally go (being the solder points for the A/V) then connect a cable and display, the electrons just start moving in that direction right? So it sounds like there isn't a lot of opportunity for a signal to be degraded/changed

[Ed Oscuro]

Basically the same reason ApolloBoy said earlier - it's easy to forget / want to sell something on, and if you've not used easily available multiout connectors, it's anybody's guess what's been done. You lose a lot of reliability in not using an engineered connector, and risk breaking something. Standardization and "if it ain't broke," basically.

If you want to get the highest video quality anyway, some systems have specific mods to bypass or alter quality-degrading circuits within consoles, or make a more direct path between RGB lines, and you still don't need to connect directly to the system.

[wyatt8740]

are there any performance related advantages or disadvantages doing this? connecting to the board?

If any, the difference will be extremely small. Unnoticeable to any human being, unless your adapters are REALLY bad.

I'd just be worried about the cable coming loose internally and shorting something. That's why I always use jacks. But those jacks do connect to the board too (at least in both of the below examples).
I actually lifted the PPU pin for video output in the famicom though, to reduce noise.

Yeah. what if your system just stops working and you need a new one? then you have to do it all over again.

think it cant happen? snes's have a weird problem where some of them just stop working one day. The power light will come on but they just give a black screen. People dont seem to know why they do it. I have a stack of them like that.

using the snes multiout is the way to go.

Replace caps and the voltage regulator (7805, my SNES at least has no thermal compound between it and the heat sink, which is bad), and you're probably good. If not, yeah, it's an extra 15 minutes of work to add the jacks to another console. After all, you already have a case with the jacks mounted, you just need to swap boards and re-solder some connections. Since SNESes don't break every other week in my experience, it's worth the 15 minutes once in a long while. I've never had a SNES break on me.

if you want few connections i think the best thing would be to make a console cable with a multiout plug that has 4 bncs on the other end.

sounds like decent advice to me, if you really consider multiple plugs to be a 'hassle'.

i really dont understand though why people make their own cables, when good cables only cost $20.00 -30.00 and the parts cost about that plus my time. but to each his own.

I have a ton of broken amplifiers and stuff, full of RCA jacks and other jacks ripe for the picking. They cost me nothing. I also have a huge amount of cat 5e cable from a neighbor (an ex-Verizon engineer).
So by making custom connections, I get essentially free cables that I don't have to wait for shipping from Europe on. Also, I don't have to deal with multiple adapters (multi-out->SCART->RGB BNC). Instead, I do RCA-out -> RGB BNC using extremely cheap RCA female to BNC male adapters.

And I at least do not make $50 in 20-40 minutes. I'll explain where I got the $50 number a bit lower down.

Retro console accessories cables are Great. Ive had no problems with them whatsoever.

Most of my problems when i first started RGB was because of CHEAPLY built scart Splitters and switches.

Yep, another reason not to use them. You buy something, wait ages for it to arrive from Europe, and guess what? It doesn't work well.
Meanwhile, I made a switcher by taking apart a composite/S-video AV switch, and replacing the S-video port with four RCA's for RGB+sync.
It was totally free (already had the AV switch), and I learned some cool stuff doing it, like how to terminate video. I have total control over my system.

Here's a little of what I have done. I experiment a lot and have a couple of things I do.
Click images for full sizes.

First, for composite/S-video systems I use DIN connectors with the same pinout as the commodore 64.
In the image of the famicom below, there wasn't really room and I wanted to not make the jack too big, since it was just about impossible to fit it in back without replacing the RF module and I'd already fried a famicom after forgetting to regulate it properly, so I was a bit weary of doing it again.

ANYWAY, I used a 6 pin mini-DIN, and a homemade adapter to VIC-20/C64 style AV output. VIC-20 uses a 5-pin DIN for composite, ground, and audio, and this worked fine for the NES. I used my already existing VIC-20 to RCA adapter to connect my famicom. Take note that this was my first ever AV mod and so it is not perfect. Also note that there is no 'official cable' for this... the Famicom only outputs RF unless you buy a ludicrously expensive AV famicom. I bought my famicom for $25 plus $15 shipping ($40).

I have also provided some internal photos. This was my first successful AV mod. There's some hot glue, but it's way better than a Drakon job

And one last close-up of the AV board work. This was originally way too big, so I chopped it down to size. The Famicom is VERY cramped internally.


The other thing I've done is on my SNES more recently. I had more space so I used RCA jacks for RGB.
If I had not done RCA jacks, my alternative was either going to be a 8-pin mini DIN or an 8 pin DIN. I love full-size DIN's for their reliability and sturdiness.


Here's a couple internal pics. I used so many caps because I didn't have many 220uf caps handy, and so I added smaller ones in parallel.

And a closeup of the jack wiring.


The NTSC SNES RGB SCART cable, on the other hand, would have cost nearly $20 ($18.32), and the SCART to RGB BNC cable from the same site would be $33.59. That's $51.91, not even counting shipping, and it's $11.91 more than my SNES 1CHIP cost from the local game store used in 2010. And for that $51.91, I get to wait for it to ship from the UK to Indiana.

The cables I use for reference are:
NTSC SNES to RGB SCART:
https://www.retrogamingcables.co.uk/sup ... -wire-cord
and
RGB SCART to BNC:
https://www.retrogamingcables.co.uk/son ... verter-bnc
Not to mention, if your monitor only accepts clean sync, and you need a sync cleaner for whatever reason, the cable with that costs an additional $10:
https://www.retrogamingcables.co.uk/son ... m-monitors
Meanwhile, the IC that strips the signal can be had for $2.94 apiece:
http://www.digikey.com/product-detail/e ... B-ND/28100
It requires three external components to operate for what we need: two common 0.1uf capacitors, and a 680 KΩ resistor, which, if you do not have it, can be made by stringing smaller resistors together for nothing.
So for the stripper, you can either spend $10, or make the circuit yourself with absolute minimal effort (under 5 minutes), to save $7.06. That's just one example.
Also, the NTSC SNES has a CSYNC output that can be tapped directly if you use your own connectors. SCART assumes composite video is where sync is taken from.

Also, it's good to be able to pick a given signal and use it somewhere else in your system. For example, if I want to use a single line (such as R/G/B/luma/chroma) as a monochrome signal, plug it into 'blue' and set the PVM to blue only mode, and hook in the external sync.
It's also useful when you want to look at something in an oscilloscope, which I do rather often.
Yeah, you can do that with pre-made cables, but it'll set you back $50.

So yeah. that's why I make custom cables instead of buying.

TL;DR If my cables cost more than my SNES, there's a problem.
Especially when I got my PVM's free (20L5 and 1944Q).

[tighecg]

thanks wyatt, I have a few more questions now, but i'll wait for them. I'm having my BVM shipped here now by UPS. From what else I've seen this may have been a bad idea. hopefully it gets here in one piece. I'm just starting out with RGB, I wanna play a bit before I start asking questions. I have not started any of my mods or cable making yet. I'm going to use composite on it for now just to get a picture on the screen and figure out the BVM. I would like to get my NES, SNES, genesis, playstation, neo geo MVS on it if any one has any specific tips on these.

[Ed Oscuro]

I'm having my BVM shipped here now by UPS.

RIP. It might survive, though, since it's a BVM and should have more metal supporting structure than the PVMs would.

If you're near a semi-big city your best bet should still be shaking all the branches for medical surplus or ex-broadcasting (if broadcasting, you'd want the equipment used by small outfits in the hopes they don't abuse them as much as regular news channels - something like a university's multimedia program ditching PVMs).

[BazookaBen]

What I did was search ebay for PVM's within 150 miles . Then I just find the seller's contact info and contact them directly. For me it was a medical equipment reseller warehouse that had dozens of PVM's.

[mvsfan]

Good luck getting that Bvm in one piece ups. one of my monitors broke in shipping.

Oh and they didnt refund my shipping costs just the cost of the monitor.

[BazookaBen]

Oh and they didnt refund my shipping costs just the cost of the monitor.

So in the end you basically paid someone to break a fully functional BVM.

Hopefully word will spread and people will stop this madness and have them shipped freight. Tired of seeing innocent BVM's slaughtered by the parcel companies.

[mvsfan]

It was a PVM, but still.

I had 1 shipped Ups and 1 shipped fedex and the one sent fedex arrived fine.

But ive heard of them breaking them too.

It probably also helped that the fedex one came in a box that was made for it, with 6 inches of soft foam on all sides.

The one that got broke came packed relatively well too. Big box, Full of peanuts and bubble wrap.

I wouldnt buy one again though unless it was local and i could pick it up.

[tighecg]

ok, the BVM got here today. no cracks in the tube or any major cosmetic damage. plugged it in and with a few pops, maybe not pops, but louder than any TV I've had. it came on. looked at a few test channels, and plugged a genesis. composite, all looks ok. what should I be looking for, or at, for signs of shipping damage? or maybe just a bad unit? anybody got a startup checklist for a BVM 20F1U and 10R? what can I check with just composite at the moment?

[mvsfan]

that noise might just be the degaussing circuit. My 14" Pvm one is rather noisy. it buzzes though not a Pop.

[Ed Oscuro]

Open it up and look at the vents (scored tops) of capacitors. Beyond that I've no idea.

[mvsfan]

another thing it could be - your flyback wire could be loose or shorting out on something. Someone gave me a tv for free a while back and when i turned it on it was crackling a bit. when i opened it up and plugged it in i noticed that the flyback wire had a small cut in it that was allowing the HV to jump to the frame.

before you mess with it though the monitor has to be properly discharged.

you really shouldnt mess with monitors unless you know how to work with High voltage. It can kill.

[Ed Oscuro]

Oh yeah - somebody here had a voltage regulator not making firm contact, so there was constant arcing across it. Definitely something to look at. Thankfully this can be spotted/fixed without current running - arcing could leave scorching, and the fix is listed below in the first thread:

http://shmups.system11.org/viewtopic.php?f=6&t=52239 <- the HVR needed silicone to re-seal its connection to the tube
http://shmups.system11.org/viewtopic.php?f=6&t=52279 <- in this case, parts were broken. However the set doesn't get far enough along in the booting sequence for arcing to happen.