AV Expansion Station for XBOX
Some time ago I was searching for replacement AV cable for my XBOX since I wanted to get new on with SPDIF -output and RGB output. I found very insteresting product sold by Console Plus: AV Expansion Station for XBox. It is a small box which is connected to XBOX and it provides optical/coaxial SPDIF output as well as analog audio output. For video there is output for S-VIDEO, composite-video and component-video (YPrPb). There is also SCART-connector which carries composite-video and audio signales (before they advertised for RGB support but it wont really support RGB and Console Plus have corrected their page now). Price is only 7.90 GBP which is cheaper than any ither RGB/SPDIF cable they sell. It indicates that this unit is crappy quality but still, it is interesting. I decided to order one (back then I though that device will support RGB) and check that what is quality of device.
Outter impressions
Device arrived in three days from UK to Finland (!!!) and I opened package. I was suprised how decent quality units chassis was. It is plastic of course, but somehow it feels well. However I was unable to get RGB to work via SCART so I thoght that I open the unit and see what's inside.
Inside
Now inside... There is simple PCB without any smart logic as expected. It seems that design of PCB is faulty - you can see some poorly sodlered jumpers to fix design flaw which routes audio out to SCART-connectors audio in :-) But don't mind about that, analog audio is not what I use and when dealing with analog audio, those jumpers probably won't do any harm.
So PCB is poor quality but it should do it's job. It's not very hard to route signals from XBOX to corresponding connectors. However, because there are no swithces, IC's or nothing inside, you cannot connect, in example, SCART/composite video and composite video somultaneously. XBOX will give only one signal for composite video and when splitted to two receivers impedance will go crazy. You propably experience dark picture ghost picture, blurry picture etc. when doing so. So use only SCART or only composite video, not both simultaneously. With audio it should not matter that much (but it will matter) so you could try to use audio-out from SCART connector and from RCA connectors simultaneously.
So in my opinion, this device does its job. It gives you plenty of connectors which you chan choose between depending on situation. Ie. you use your at your home using component video for your video projector or HDTV and optical out for your stereo equipment. Then you take your XBOX to your friends place and hook it up using composite video / analog audio or SCART. No need to buy many cables since this box will offer you everything (but RGB) XBOX is cabable to output. Of course you need SCART cable, YPrPb cable etc. extra cables, but you should have received them in any case with your HDTV etc.
Oh and one thing - SCART connector is VERY VERY poorly soldered to
PCB. First, is soldered only from 8 points. Secondly connectors clips
are not conneced any way to PCB. So if you remove/replug SCART
connector often it will definetly break. If you do RGB mod instructed
below, you can use epoxy glue to make it more sturdy.
Picture quality
Quality of picture is most important thins most of people wan't to know (at least I hope so). Now I am no expert but I think biggest thing affecting quality is cables from this unit to your television/projector/etc. So buy properly screened and wired cables. Ie. some cheapest SCART cable is wired using non-coax cables with video signal and whole cable is without screening. But then again, some most cheapest cables are well built. Go figure. Just ask from cleric if this SCART cable is wired using 75 ohm coax cables inside and if he doesn't know, ask somebody else. You can draw conclusions from thickness of cable - more thicker, usually better.
It seems cable from XBOX to this unit is good quality cable too, using coax cables etc. However, unit itself isn't screened for radio interferences and definetly is not impedance balanced. However since unit is so small, that should not affect to picture quality as long as you use only one output from unit like stated above). Don't know what is case with HDTV modes though, above is true for PAL/NTSC modes. It may be that with HDTV non-properly blanced impedance will cause some visible faults in picture.
Why no RGB?
One could ask that why there are no RGB support in SCART -connector. I mean, about every single TV in Europe (at least manfactured no longer than 10 years ago) will support RGB and picture quality using RGB is superior (most European televisions wont support YPrPb so you can't use it). It is also so that XBOX is perfectly cabable to output RGB and it is also so that when selecting right "mode" for XBOX, RGB will be outputted to same pins than YPrPb and sync singnal is outputted to composite video connector. It means that it would only take few extra connections to SCART in PCB and one extra position for mode selection switch in box. But no.
Propably this is because this device is manufactured somewher far far away where they don't even know what SCART is (it is European thing). The fact that SCART is wired faulty and then fixed manually supports this. So they just haven't had any decent designer for this product, which is sad.
Hey could you add RGB by yourself?
Now we are talking. Yes you can and it's extremely easy as well. When looking XBOX AV connectors pinouts wee see that pins 17, 18 and 19 controls what type of cable is plugged in. Depending on selection pins 24, 22, 11 and 9 will output different types of signal. Like this (X marks grounded pin, V = composite video, C = Chroma, Y = Luma):
| 17 | 18 | 19 | Mode | 24 | 22 | 11 | 9 |
|---|---|---|---|---|---|---|---|
| X | NTSC Mono | V | C | Y | - | ||
| X | PAL/Secam Mono | V | C | Y | - | ||
| X | X | Component | - | Y | Pr | Pb | |
| X | NTSC Stereo | V | C | Y | - | ||
| X | X | PAL Stereo | V | C | Y | - | |
| X | X | X | RGB | V | R | G | B |
Because unit is cabable of producing component and PAL video, it must be so that switch in unit will connect pin 18 to pins 17 or 19 depending on switch positin. So we can put XBOX in RGB mode simply by adding switch which will connect pins 17 and 19 when closed. Then XOX will output RGB no matter in which postion original mode selection switch is and when RGB-switch is opened, original mode switch will work normally. This is most simple way to do this, of course you can get three position switch and replace original switch with it.
Ok then let's look PCB. There goes four lines to switch. Lets call them 1, 2, 3 and 4 beginning from inside of unit. When switch is switched to component video it will close lines 1 and 2 and whiech switched to composite video iw till close lines 3 and 4. So we can map lines to AV connector pins: 1 == 19, 2,3 == 18, 4 == 17. This can be confirmed with multimeter too. However, I am not sure why there are two lines, 2 and 3. It is possible that switch connects something else too than pins 17, 18 and 19. Can't figure out from pinouts what it could be and my multimeter is so poor that I don't want te measure them either. Please do so and email results to me if you got better one. However I found that XBOX will go to RGB mode like expected, when shortcutting lines 1 and 4. Solder wires to connector and solder switch to wires and mount switch to covers. Should be no problem for anyone.
After doing this you can get RGB output from same connectors you get YPrPb. Connectors are even colord coded and indeed you will get red signal from red connector (Y), green from green (Pr) and blue from blue (Pb). Also you get composite sync from yellow composite video connector. If your telly has RCA/BNC connectors oy won't need to do anything else, just connect these connectors to your telly using 75 ohm coax cable (and perhaps RCA->BNC adaptors)
Probably you need RGB to routed to SCART connector. That is easily done. Just solder wires from component video connectors in PCB to SCART connector. Please see SCART pinouts. Red goes to ping 15 blue to 7, green to 11. You proabably won't even need to solder R/G/B grounds since grounds are connected to same point in television and you already get ground via already-connected composite video ground. But if you wan't to do this properly, connect also grounds (pins 5, 9 and 13) to somewhere to PCB ground. Easiest point is compsite video ground which I connected these to.
Please notice that for best results, use thin 75ohm coax cable for color signals. I used normal diode wire which was only wire I had in my toolbox. Propably I'll switch those wires to coax wires which makes grounding also easier.
This should be enough for most tellys but it is possible that your television will not autodetect RGB signal but fallbacks to composite video. You ay be able to force TV manually to RGB mode but to be more compatible, you must use SCART connectors blanking signal (pin 16, pin 18 for blanking ground). When feeding blanking pin with 1-3 VC, telly should go to RGB mode. You can do this by taking +5 VC from line powering optical out and connect it to blanking pin using ~100 ohm resistor. Use multimeter to find +5V or see picture below very carefully. WARNING! Do not connect +5V to blanking directly. Depending on your TV, something may break.
This should do it. If you can't get RGB picture to your telly (you can definetly say difference between RGB and composite video), triple-check all our connections, check pinouts that I haven't make any typo in this page and use multimeter to measure that you get signals needed (or oscilliscope would be better :).
With original/equipment RGB cable you get your telly to switch to SCART input whenever you poweron your XBOX. This is done by feeding SCART connectors pin 8 with suitable current (0-2V TV, 5-8V 16:9, 9.5-12V 4:3). AFAIK XBOX won't support automatic aspect ratio signaling but instead it just feeds something fixed to telly (probably 16:9 signal?). At leats if there are this functionality, it is not brung to this expansion station. Also there is only +5V found in expansion station so best you can get is 16:9 signal. It's ok if you use widescreen TV but may cause problems if you have smart 4:3 TV which will add extra black borders when detecting 16:9 signal. Probably you can switch aspect ratio manually though in our TV. But just connect +5V to pin 8. It will enable auto switching to AV channel when XBOX is powered on. Add resistor for safety, I found that when I add ~100 ohm resistor it's still ok (voltage is something 4.6V when connected to TV). Use smaller resistor if voltage drops too low. AFAIK you can connect +5V directly to pin 8 also without any harm (unlike to pin 16 for which you need resistor!), but I can't quarantee that. I'll add pictures soon for this mod, I have done this and it works flawlessly.
More pictures
Please see my gallery for more pictures about this device.
Disclaimer
I take no responsibility if you do these modifications. I have no training in electronics so I may instruct something very horrible wrong. some kind of electronics in official cable, sun spots etc.). So everything you do, you do at you own risk!