How can set to display only 1 top news in the news ticker?

Until you get some true Drupal advice (i.e., I am NOT a Drupal Expert), you can see if you can just manage this from the MySQL database side by using ORDER BY DateAddedColumn DESC LIMIT 1 -- i.e., whatever column denotes when a news item was added or updated should be used in order by descending so that the top most record is the latest news article, then just use limit to get the top x records. From .NET, if you did any MS SQL queries, this would be like SELECT TOP 1 ... ORDER BY DateAddedColumn DESC. In MySQL, it just goes at the end, e.g., SELECT ... ORDER BY DateAddedColumn DESC LIMIT 1.

Good luck!

I search Drupal category but didn't find it.  Thank you for adding it.  Can yo move Drupal up as the primary zone?  Thank you.
I'm not sure this is MYSql issue but thank you for the suggestion.

It seems that the news ticker is a Drupal's  'view'.
If so go to admin/build/blocks, and check which block is positioned at the header region.
Go to admin/build/views, and look for the specific 'view' in the list and edit it.
in "Basic settings" at "Items to display" select 1.
In "Sort criteria" select node ID and "descending"
This should do it.

Mw, is newsticker.module the name of the php file?  there are lots of file for this site and i only get FTP into the drive so it's hard for me to find where that file is. But thank you for your help.

Ha, I found the header view is "uscuh" but then in the View I cannot find that view to edit.  Can you have a look at the screen shots and let me know if you can see which view I'm to edit?  Thank you.
Blocks-1318081059615.jpeg
Administer-views-1318081630829.jpeg

HagayMandel for the win.

I thought the same thing since that's the only view with "homepage" keyword.  I didn't find anything that has number 5 or indicate it's news.  I attached a screen shot for your review.  Also, I don't know if this matters but on the top of the home page, PressRoom, is where all the news are.  The news ticker pulls the top 5 news from there.  

I really appreciate help with this.  We lost our PHP Drupal person and still hasn't found a replacement.  If I can't figure out how to do this then I'll have to do something ugly like creating 5 top news to be exactly the same so it keeps displaying the news title. We have an important news that needs to be up by Monday morning and stay there for a few days.
Edit-view-scientific-papers-news.jpeg

I thought the view option to change would be your best bet, but since you asked -- yes, the .module file appears to be the PHP code. However, when you download newsticker, it is in a .module file. I would exhaust the GUI method first before customizing the PHP, but my changes should work if you can locate the file with the functions I noted.

Look carefully in your screen shot, aside Nodes per Block: is is indicating 6.
Change it to 1.
(I'm sorry, it's Drupal 5, and I lack knowledge about this version).

I noticed the number 6 as well but I counted it before and it is only pulling top 5 news.  Anyway, I changed it to 1 just to make sure and that didn't affect the news ticker.  

Thanks.  I found it in the PHP file.