eBay MAK Supergun

[mannerbot]

http://cgi.ebay.com/ws/eBayISAPI.dll?Vi ... eName=WDVW

I see this supergun on eBay all the time, why is it so low-priced compared to most?

[llaoyllakcuf]

why is it so low-priced compared to most?

likely because it only outputs straight RGB video & nothing else
- so anyone living in Europe can simply plug it into a TV.


those special video convertor circuits (for component, s-video, composite)
that are found in most NTSC superguns are expensive..


also, it doesn't seem to include joysticks or controllers of any kind

[mannerbot]

Yes, but even other bare-bones superguns are much more expensive. I thought that the commonly used JROK converter would be the most expensive part of a supergun, and that one without said converter would carry a significantly lower price tag, but that is not the case.

On a related note, what would it take to modify the cable for output to a Commodore 1084s or similar monitor?

[raiden]

On a related note, what would it take to modify the cable for output to a Commodore 1084s or similar monitor?

a Scart and a 1084 pinout diagram, a 9pol. SubD-plug and less than half an hour of solder work. However, if you ask the guy to send you a 1084 cable instead, he´ll probably be able to so and shouldn´t charge you extra, as it´s less work for him than building the Scart cable. The supergun already has a 9pol. SubD port to connect the custom Scart cable to, maybe that one is already made for 1084 norm, so you could just use a pin joystick extension cord to connect the supergun to a 1084. I´d just ask the guy if that happens to be the case.

[oxtsu]

Yes, but even other bare-bones superguns are much more expensive.

The price for the one you linked to seems like a good deal, but it's not that much less than a similarly featured model. The components are costing only half of the selling price I would guess. This design is near the lowest cost possible as well (lacking NTSC convertor, controllers, full JAMMA harness, arcade power supply, etc.) Also, the price will vary depending on the maker and quality (private vs. business, etc).

I thought that the commonly used JROK converter would be the most expensive part of a supergun, and that one without said converter would carry a significantly lower price tag, but that is not the case.

Well, in general it's still true. Not having the NTSC convertor is going to lower the price between $40-100. There's a few things that are more expensive though, like a set of custom arcade sticks or an arcade power supply (Japan made one). Then there are the other little details that add up in price more significant.

Good luck in your hunt for PCB land.

[mannerbot]

Thanks for all the info, guys. Since it seems like these cheapie superguns aren't worth my time, so I'll just have to see about getting a custom.

[iatneH]

Actually, I've never seen these compact superguns, and looking at the bare-bones-ness of it, I think I'll take the plunge and build my own since it looks do-able for me (and I probably won't have any explaining to do like I would if I suddenly showed up at my house with a full cabinet), but I'll be shelling out the bucks for a jrok. I'll probably mod a couple of 3-button Genesis pads for it at first, then upgrade to custom sticks later on.

I like the idea of that compact laptop-ish power supply, but I'm not sure if they are safe to use for PCBs... can anyone give me some facts here?

[iatneH]

It has begun...

I will begin construction soon, I've already ordered a JAMMA harness and a full set of joysticks and enough pushbuttons for two players, and the smaller components I will purchase locally.

Right now I'm leaning towards getting a JROK since I'm lazy, although I did in fact find a schematic for a RGB -> NTSC circuit. I damn nearly ordered the IC needed for it too, but I think in the end, after buying the rest of the components needed to build the circuit, the cost might be close to a JROK, with much less professional workmanship and a less compact package.

One of the things bothering me though is the power supply. I read somewhere that as long as the supergun isn't going to be used in a cabinet with an arcade monitor, only +5V is needed. Does this mean I can use an external transformer, say for example something like a PSP charger?

I'm thinking of how I'll do the coin buttons too. Maybe I'll build a "fake" coin mechanism, basically just a slot in the box with a ramp and a microswitch that the coin triggers as I force it into the slot (and there will be a dish into which the coin exits the box), and just a plain old button for when I'm feeling too lazy or don't have a coin :p

[raiden]

I like the idea of that compact laptop-ish power supply, but I'm not sure if they are safe to use for PCBs... can anyone give me some facts here? (...)
One of the things bothering me though is the power supply. I read somewhere that as long as the supergun isn't going to be used in a cabinet with an arcade monitor, only +5V is needed. Does this mean I can use an external transformer, say for example something like a PSP charger?

Jamma specs list +5V, -5V and +12V. However, if you are mainly interested in games after 1990, you don´t need to worry about -5V, as almost all modern games don´t need it anymore. +12V is usually taken for sound, so you might get a game running with +5V only, but it´s not much fun without sound, is it?
Those compact laptop-ish power supplies are unlikely to damage your PCBs if you wire everything right, but they might be too weak, especially for old games which draw more power than newer ones. A weak PSU can overheat when used for too long, so you should be careful about that. Don´t leave a hot PSU on when leaving the room.
PC PSUs are powerful enough, however they generally create noise, and in a few cases even graphic errors if the voltage is not precise enough. One good thing about them is that they carry also 3,3V in case you want to power a Naomi, Model3 or such thing.
To cut costs while starting out, both options are viable. However, once you have a few games or a really expensive one, taking care they don´t get damaged slowly over time by inferior PSU quality becomes more important, so at that point you will want to change to an arcade PSU anyway. If you´re sure you will pursue the PCB hobby, you might just as well get the real deal at once.

[iatneH]

Thanks for the tips raiden, I'll see what I can get at the local electronics shop.
I won't be buying any of the big guns PCBs like Ketsui at the moment so I'm not too worried. Once I know I can do it, it won't be too much trouble for me to swap out parts later on.

[iatneH]

Phew... bought a crapload of stuff today from my favourite mom & pop electronics store (finally got my own multimeter too :p )

I couldn't find a compact power supply, but I DID find an actual arcade power supply with the whole +5V, +12 V, and -5V deals. That was quite a surprise, Ms. Lee said they got it from an arcade operator, so it ought to work for me :)
I think it's probably the only one they ever had, and the only one they'll ever have, and I bought it. What a stroke of luck!
It's pretty big though so I won't be able to use the project box I have from earlier, and I didn't have enough money for a bigger project box.

...now I just need PCBs and a JROK :\

[raiden]

It´s better to have an external PSU anyway. If you happen to get into a "building frenzy" like I did and, for example, want different superguns for tate and yoko, or want a dedicated supergun just for MVS, you can use the PSU for all of them. Also, you can use different PSUs when a problem occurs to find out where it comes from.
Having a multimeter is extremely useful, especially to minimize errors. In case you haven´t bought wires already, I´d recommend getting several different colors, which makes checking connections much easier once you have a box full of them. Following each wire by finger is just too bothersome in the long run.