HELP EXPLAIN MONITORS & ARCADEVGA

[popeye]

I am hoping someone out there can give me some tips on what monitor I should get.  I bought a gutted arcade cab that has brackets built in that can hold a 24 or 25 inch monitor.
The cab will only be used for mame.  The games I plan on playing will be from the early to mid eighties to the early nighties(haven't really sorted through the games if I do i'll never finish the cab)

What I would like to know is what is the difference between a 15khz and 30khz monitor?
If an Arcadevga puts out a 15khz signal how does this affect a 30khz monitor?
Will I need a video amp like the one from ultimarc?  
What brand of monitor do people recomend that is 24 or 25 inch?

[Harry Potter]

What I would like to know is what is the difference between a 15khz and 30khz monitor?

15khz monitors are generally TVs and older Arcade monitors. There is a 25khz sub-set of arcade monitors but they are generally a pain to set up unless you're an expert in AdvanceMAME

If an Arcadevga puts out a 15khz signal how does this affect a 30khz monitor?

Simple. It won't work. Unless you use a WG D9200 monitor which has support for the 15khz-31khz range, but these things are about $600US. The arcadeVGA has a software patch which allows it to run in 31khz mode in 640x480 and 800x600. But that kinda negates the whole point of the card.

Will I need a video amp like the one from ultimarc?  

If you decide on an old arcade monitor, then most likely yes, otherwise, trial and error.

What brand of monitor do people recomend that is 24 or 25 inch?

If you're still set on an Arcade VGA then:
Wells Gardener D9200 if you have lots of $$$. Otherwise you can either stick in a TV with SCART input or scavange an old arcade monitor from an arcade place/repair shop.

[wpcmame]

What I would like to know is what is the difference between a 15khz and 30khz monitor?

The number represents the number of lines the monitor can draw in one second. A 15KHz monitor can draw approx 15700 lines in one second. It means that if you want 60 frames per second, you are limited to 15700/60=261 lines per frame. You can't use some  lines since they are reserved for the beam to travel back to the top left corner. In practice you can use 240lines at 60Hz or 288 lines at 50Hz.
With a 31kHz monitor you can use approx 480lines at 60Hz and 576lines at 50Hz.

Note that (almost) all graphic cards can output a 15kHz signal. The main difference with the arcadeVGA is that it got some 15kHz display modes in BIOS. This means that programs (e.g. windows and MAME) can use these modes directly without any special drivers.

Will I need a video amp like the one from ultimarc?  

Depends on the graphic card and the monitor. Most graphic cards output 1V which is ok for most monitors but some (mostly older) monitors requires 5V and then you need an amplifier.

What brand of monitor do people recomend that is 24 or 25 inch?

For arcade use only it doesn't matter since it is mostly other features that differs. Find one that fits, physicly and electronicly, in the cabinet.