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Main => Monitor/Video Forum => Topic started by: Jabberwocky on May 24, 2004, 11:10:22 pm

Title: WG K7200A Question
Post by: Jabberwocky on May 24, 2004, 11:10:22 pm
Hello,

i'm sorry if this has been covered allready somewhere else. I did a search in this forum, but didn't find anything that answered this question:

Recently i bought a new 19" WG K7200A (revision A - 7203-chassis) universal mount monitor for my cab, but as my cab isn't finished yet, i didn't try the monitor before mounting it (like it fully discharged when mounting ;-)).

I will be using the ArcadeVGA connected to it, but one thing that bothers me, is that i can't seem to find any trace of a v-hold-control on this monitor. And everywhere i read about the necessitiy for adjusting the v-hold for a stable picture. h-hold is there but not v-hold, not even in the schematics (and i really looked with eagle-eyes around ;-)).
I know the older chassis (7201) for the K7200 had a clearly visible v-hold from the specification-PDF on the WG site.
I realized also that in the new revision a different v-sync-circuit is used (not the one from IC LA7851: the v-sync part is grounded), namely a dedicated v-sync IC TDA1675A.

Maybe that's the clue? Does this monitor maybe sync itself automatically to the vertical sync in it's range (from 47 to 63 Hz) without the need for an adjustment? Or have i really overlooked something?
Maybe someone here in this forum has allready some experience with the K7200A and can tell me for sure what's the case.

Many thanks for your help
Neni
Title: Re:WG K7200A Question
Post by: Ken Layton on May 25, 2004, 01:05:19 am
The 7200 series has a vertical hold control on the remote adjustment board. If in doubt, phone Wells-Gardner direct and talk to tech support.
Title: Re:WG K7200A Question
Post by: Jabberwocky on May 25, 2004, 08:49:49 pm
Thanks, yep, that's true for the 7201 revision chassis but not for the 7203. The newer one has 'only' the following controls on the remote board: h-position, h-size, v-position, v-size, black level, contrast.

So on the 7203 the h-size moved to the remote board (on 7201 it was on the chassis and v-hold was on the remote) and v-hold disappeared into thin air ;-).

So probably it's the best if i call WG directly (actually e-mail them; i'm in Switzerland) and ask them about this. I just thought that maybe someone else here has also a new K7200A and can give me some insight from user to user :-).

Kind regards
Neni
Title: Re:WG K7200A Question
Post by: Jabberwocky on May 26, 2004, 08:19:01 pm
I received a helpful answer from WG technical support. I will post it here just to let you all know (will maybe be helpful for someone else also).

In short, my question was: "Are these new K7200A somehow able to sync themselves automatically to any v-sync in the supported range (47 - 63 Hz) or am i overlooking something?"

Answer from WG technical support:
Quote
Hello Neni
 
Yes the K7200 Rev "A" (the newer style) has a automatic lock in for the vertical so there is no adjustment. The older style K7200 did not have this circuit so a manual control was applied. I hope this information helps if not let us know.

So this sounds really good: no need to mess around with v-hold :-).

Regards
Neni