You don't say which portal you are using - this is what I've used with EzPortal:
global $modSettings, $txt, $scripturl, $context;
// make sure newletter is installed and enabled
if (!empty($modSettings['newsltr_news']) OR !empty($modSettings['newsltr_events']) OR !empty($modSettings['newsltr_topic_count']))
{
$context['user']['newsltr'] = array('next_ltr_date'=>'', 'period'=>'', 'email'=>'',);
if (!$context['user']['is_guest'])
{
global $smcFunc;
$result = $smcFunc['db_query']('', '
SELECT email, next_ltr_date, period
FROM {db_prefix}hcb_newsletter
WHERE email = \'' . $context['user']['email'] . '\'
LIMIT 1'
);
if ($row = $smcFunc['db_fetch_assoc']($result))
$context['user']['newsltr'] = $row;
$smcFunc['db_free_result']($result);
}
echo '
<div class="smalltext">
<form action="',$scripturl,'?action=NewsSubscribe" method="post" accept-charset="',$context['character_set'],'" name="newsSubscriber">
<input type="hidden" name="sc" value="', $context['session_id'], '" />
<input type="hidden" name="lastaction" value="forum" />';
if ($context['user']['is_guest'])
echo $txt['newsubscribe_mod_email'] . '<input type="text" clasa="input_text" maxlength="255" size="25" value="' . $context['user']['newsltr']['email'] . '" name="email" />';
else
echo '
<input type="hidden" name="email" value="', $context['user']['email'], '" />';
if ($context['user']['is_guest'] OR empty($context['user']['newsltr']['email']))
echo '
<input type="submit" class="button_submit" name="subscribe" value="' . $txt['newsubscribe_mod_subscribe'] .'"/>
<br /><Input type="radio" name ="period" value="7"' . (($context['user']['newsltr']['period'] == 7) ? ' checked' :'') . '>' .
$txt['newsubscribe_mod_week'] . '
<br /><Input type="radio" name ="period" value="14"' . (($context['user']['newsltr']['period'] == 14) ? ' checked' :'') . '>' .
$txt['newsubscribe_mod_fort'] . '
<br /><Input type="radio" name ="period" value="30"' . ((empty($context['user']['newsltr']['period']) OR $context['user']['newsltr']['period'] == 30) ? ' checked' : '') . '>' . $txt['newsubscribe_mod_month'];
if ($context['user']['is_guest'] OR !empty($context['user']['newsltr']['email']))
echo ($context['user']['is_guest'] ? '<br />' : $txt['newsubscribe_mod_next'] . date(' j F', $context['user']['newsltr']['next_ltr_date'])) . '<input type="submit" class="button_submit" name="unsubscribe" value="' . $txt['newsubscribe_mod_unsubscribe'] .'"/>';
echo '
</form>
</div>';
}
