25" RGB TV I found in the UK

[benwillcox]

Hello All,

Just thought I'd post my experience of finding a suitable RGB 25" TV in the UK for my mame cabinet.

Basically I could only find TWO 25" models (most are either 21 or 28"), both of these in Comet, a Goodmans 258NS for

[DaveJ-UK]

SCART is RGB isn't it?

This diagram would probably be quite helpful with a similar project: http://www.digitalspy.co.uk/satellite/scart/

[DaveJ-UK]

Just browsing your website, I see you have that diagram already posted, although it doesn't go into quite as much detail.

I also notice you are using a pair of speakers from Halfords. You should use shielded speakers in your cab to elminate (or at least minimise) interference with the monitor. Unfortunately I don't think Halfords stock shielded speakers (I asked in there a couple of weeks ago) and the only place I could find that stocked them was Maplins.

Something like product code L77AA at http://www.maplin.co.uk/

(I would post the actual link but it uses frames )

[benwillcox]

SCART is RGB isn't it?

No, SCART is simply the type of connector used, which provides the capability to use S-video, composite, and RGB connections, as well as various audio and sync signals.  Not all devices support all the connections although these days the vast majority support RGB on the SCART connection, although a few years ago I don't think that was the case, especially on the cheapo models.

TV's cannot support all the video connection methods on a single SCART connector - for example S-video was added to the standard later, I belive, and uses pins that would normally be used by RGB. Therefore you cannot have RGB and S-Video supported on a single SCART connection. Big TV's usually have 2 though, with RGB on one and s-video on another (This goodmans does s-video on AV2).

More details of the different signal connections can be seen here: http://utopia.knoware.nl/users/eprebel/SoundAndVision/Engineering/SCART.html

Cheers,
Ben

[benwillcox]

Just browsing your website, I see you have that diagram already posted, although it doesn't go into quite as much detail.

Yes I do need to update my website a bit anyway as a few bits are missing. I will do soon though!

I also notice you are using a pair of speakers from Halfords. You should use shielded speakers in your cab to elminate (or at least minimise) interference with the monitor. Unfortunately I don't think Halfords stock shielded speakers (I asked in there a couple of weeks ago) and the only place I could find that stocked them was Maplins.

Well I've heard people say this before, but I'm not totally convinced. Were shielded speakers used in the real arcade machines?
As I understand it shielded speakers are only needed for things like computer speakers or surround centre speakers where they're actually stuck right to the side of the television case. In fact, the speakers inside the TV that I removed were not shielded AFAIK and they were 2 inches from the tube!

The speakers I've used are a good 6 or 8 inches from the tube, and I havn't noticed any problems.....


Cheers,
Ben

[benwillcox]

In fact, the speakers inside the TV that I removed were not shielded AFAIK and they were 2 inches from the tube!

OK to correct myself I've just done some searching and it appears that internal TV speakers are in fact shielded. I suppose I should have known that that close they would have to be!

I still would have thought that in an arcade cab they are too far away to affect the tube... Can anyone confirm what are used in real cabs?

Cheers,
Ben.

[DaveJ-UK]

I had a horrible dark area on the right of the screen until I replaced the speakers with new shielded ones. The speakers are almost a foot from the tube.

I paid just under a tenner for the pair and they're more than enough to play the game  sound and a bit of music. I used the amp from a pair of Dell PC speakers.

I would be very surprised if many cabs from decent manufacturers originally had unshielded speakers, especially as they only cost pennies more.

[benwillcox]

I would be very surprised if many cabs from decent manufacturers originally had unshielded speakers, especially as they only cost pennies more.

Hmm, I guess you're right.
Maybe I've just been lucky then as I see no colour distortion at all with this setup.... However, my monitor isn't in it's permanent mounting position yet so I will have to wait and see.
Funnily enough, I have found a pair of 4 inch shielded speakers, however the sound quality compared to the Kenwood ones is really awful and muffled. I think these ones I found are just very poor quality, or broken.

Cheers,
Ben.

[benwillcox]

Maybe I've just been lucky then as I see no colour distortion at all with this setup....

Hey Dave I think you're right about the sheilded speakers, as I've started to notice that when the screen's been on for a while I am getting a pink tinge to the picture in the middle.  Thanks for the tip, I'll have to find some decent 4" shielded speakers now!

Cheers,
Ben