Any ideas how to make an excerpt longer

Insert this into your functions.php file to control the length of the excerpt by characters NOT words

function the_content_limit($max_char, $more_link_text = 'Read more »', $stripteaser = 0, $more_file = '') {
    $content = get_the_content($more_link_text, $stripteaser, $more_file);
    $content = apply_filters('the_content', $content);
    $content = str_replace(']]>', ']]>', $content);
    $content = strip_tags($content);

   if (strlen($_GET['p']) > 0) {
      echo "<p>";
      echo $content;
      echo "&nbsp;<a href='";
      the_permalink();
      echo "'>".__("Read more")." &raquo;</a>";
      echo "</p>";
   }
   else if ((strlen($content)>$max_char) && ($espacio = strpos($content, " ", $max_char ))) {
        $content = substr($content, 0, $espacio);
        $content = $content;
        echo "<p>";
        echo $content;
        echo "...";
        echo "&nbsp;<a href='";
        the_permalink();
        echo "'>".$more_link_text."</a>";
        echo "</p>";
   }
   else {
      echo "<p>";
      echo $content;
      echo "&nbsp;<a href='";
      the_permalink();
      echo "'>".__("Read more")." &raquo;</a>";
      echo "</p>";
   }
}

Use it in your theme like this

<?php the_content_limit(245); ?>

Insert this into your functions.php file to control the length of the excerpt by characters NOT words

function the_content_limit($max_char, $more_link_text = 'Read more »', $stripteaser = 0, $more_file = '') {
    $content = get_the_content($more_link_text, $stripteaser, $more_file);
    $content = apply_filters('the_content', $content);
    $content = str_replace(']]>', ']]>', $content);
    $content = strip_tags($content);

   if (strlen($_GET['p']) > 0) {
      echo "<p>";
      echo $content;
      echo "&nbsp;<a href='";
      the_permalink();
      echo "'>".__("Read more")." &raquo;</a>";
      echo "</p>";
   }
   else if ((strlen($content)>$max_char) && ($espacio = strpos($content, " ", $max_char ))) {
        $content = substr($content, 0, $espacio);
        $content = $content;
        echo "<p>";
        echo $content;
        echo "...";
        echo "&nbsp;<a href='";
        the_permalink();
        echo "'>".$more_link_text."</a>";
        echo "</p>";
   }
   else {
      echo "<p>";
      echo $content;
      echo "&nbsp;<a href='";
      the_permalink();
      echo "'>".__("Read more")." &raquo;</a>";
      echo "</p>";
   }
}

Use it in your theme like this

<?php the_content_limit(245); ?>