diff --git a/README.md b/README.md
index 3c11365..afe0ea7 100644
--- a/README.md
+++ b/README.md
@@ -169,7 +169,7 @@ The dashboard provides several tabs:
 
 1. Navigate to the **Messages** tab
 2. Type your message in the text field
-3. Select the channel (0-7)
+3. Choose a device to send **From**
 4. Click **Send**
 
 Messages will be broadcast to the mesh network via MQTT.
@@ -269,6 +269,12 @@ Log level can be configured with `LOG_LEVEL` in `.env` (debug, info, warn, error
 3. Check that there is active mesh traffic on the topic
 4. Review logs for any error messages
 
+### Messages sent over MQTT aren't sent over the radio
+
+1. Ensure the sending radio (node) has a channel called "mqtt"
+2. Ensure the node has Uplink and Downlink enabled on both the default channel (LongFast, etc) and the mqtt channel
+3. Ensure the node's setting under LoRa is "Ok to MQTT"
+
 ### Database errors
 
 1. Ensure the `data/` directory is writable
diff --git a/public/index.html b/public/index.html
index c033224..55a04fa 100644
--- a/public/index.html
+++ b/public/index.html
@@ -118,6 +118,11 @@
                             <select id="message-from">
                                 <option value="474572292">!1c496604</option>
                             </select>
+                            <select id="message-channel">
+                                <option value="0">LongFast (public)</option>
+                                <option value="1">Aether (private)</option>
+                                <option value="2">Other (2)</option>
+                            </select>
                             <button type="submit" class="btn btn-primary">Send</button>
                         </div>
                     </form>
@@ -159,13 +164,18 @@
                     <p>Purge old data from the database to free up space.</p>
                     <form id="purge-form" class="settings-form">
                         <div class="form-group">
-                            <label for="purge-days">Keep data from the last:</label>
-                            <select id="purge-days">
-                                <option value="7">7 days</option>
-                                <option value="14">14 days</option>
-                                <option value="30" selected>30 days</option>
-                                <option value="60">60 days</option>
-                                <option value="90">90 days</option>
+                            <label for="purge-hours">Keep data from the last:</label>
+                            <select id="purge-hours">
+                                <option value="1">1 hour</option>
+                                <option value="6">6 hours</option>
+                                <option value="12">12 hours</option>
+                                <option value="24">1 day</option>
+                                <option value="72">3 days</option>
+                                <option value="168">7 days</option>
+                                <option value="336">14 days</option>
+                                <option value="720" selected>30 days</option>
+                                <option value="1440">60 days</option>
+                                <option value="2160">90 days</option>
                             </select>
                         </div>
                         <button type="submit" class="btn btn-danger">Purge Old Data</button>
diff --git a/public/js/app.js b/public/js/app.js
index 3905b40..11c456e 100644
--- a/public/js/app.js
+++ b/public/js/app.js
@@ -173,17 +173,17 @@ const api = {
         return this.request(`/api/messages?limit=${limit}`);
     },
 
-    async sendMessage(from, text) {
+    async sendMessage(from, text, channel) {
         return this.request('/api/messages/send', {
             method: 'POST',
-            body: JSON.stringify({ text, from })
+            body: JSON.stringify({ from, text, channel })
         });
     },
 
-    async purgeData(days) {
+    async purgeData(hours) {
         return this.request('/api/purge', {
             method: 'POST',
-            body: JSON.stringify({ days })
+            body: JSON.stringify({ hours })
         });
     },
 
@@ -547,9 +547,10 @@ document.getElementById('send-message-form')?.addEventListener('submit', async (
 
     const text = document.getElementById('message-text').value;
     const from = parseInt(document.getElementById('message-from').value);
+    const channel = parseInt(document.getElementById('message-channel').value);
 
     try {
-        await api.sendMessage(text, from);
+        await api.sendMessage(from, text, channel);
         document.getElementById('message-text').value = '';
 
         // Reload messages after a short delay
@@ -1045,14 +1046,23 @@ document.getElementById('refresh-map-btn')?.addEventListener('click', loadMap);
 document.getElementById('purge-form')?.addEventListener('submit', async (e) => {
     e.preventDefault();
 
-    const days = parseInt(document.getElementById('purge-days').value);
+    const hours = parseInt(document.getElementById('purge-hours').value);
 
-    if (!confirm(`Are you sure you want to delete data older than ${days} days? This cannot be undone.`)) {
+    // Format time period for display
+    let timePeriod;
+    if (hours < 24) {
+        timePeriod = `${hours} hour${hours !== 1 ? 's' : ''}`;
+    } else {
+        const days = hours / 24;
+        timePeriod = `${days} day${days !== 1 ? 's' : ''}`;
+    }
+
+    if (!confirm(`Are you sure you want to delete data older than ${timePeriod}? This cannot be undone.`)) {
         return;
     }
 
     try {
-        const result = await api.purgeData(days);
+        const result = await api.purgeData(hours);
         alert(`Successfully purged:\n${result.deleted.messages} messages\n${result.deleted.positions} positions\n${result.deleted.telemetry} telemetry records`);
 
         // Reload stats
diff --git a/src/database/queries.js b/src/database/queries.js
index 2d62a04..e9dbc93 100644
--- a/src/database/queries.js
+++ b/src/database/queries.js
@@ -95,7 +95,7 @@ const positionQueries = {
   `),
 
   deleteOldPositions: db.prepare(`
-    DELETE FROM positions WHERE timestamp < datetime('now', '-' || ? || ' days')
+    DELETE FROM positions WHERE timestamp < datetime('now', '-' || ? || ' hours')
   `),
 
   getPositionTrails: db.prepare(`
@@ -170,7 +170,7 @@ const messageQueries = {
   `),
 
   deleteOldMessages: db.prepare(`
-    DELETE FROM messages WHERE created_at < datetime('now', '-' || ? || ' days')
+    DELETE FROM messages WHERE created_at < datetime('now', '-' || ? || ' hours')
   `)
 };
 
@@ -199,7 +199,7 @@ const telemetryQueries = {
   `),
 
   deleteOldTelemetry: db.prepare(`
-    DELETE FROM telemetry WHERE timestamp < datetime('now', '-' || ? || ' days')
+    DELETE FROM telemetry WHERE timestamp < datetime('now', '-' || ? || ' hours')
   `)
 };
 
diff --git a/src/mqtt/client.js b/src/mqtt/client.js
index 80a2ed9..0bbd327 100644
--- a/src/mqtt/client.js
+++ b/src/mqtt/client.js
@@ -344,10 +344,11 @@ class MeshtasticMQTTClient {
   }
 
   // Send a text message
-  async sendTextMessage(from, text) {
+  async sendTextMessage(from, text, channel=0) {
     try {
       const message = JSON.stringify({
         from: from,
+        channel: channel,
         type: 'sendtext',
         payload: text
       });
diff --git a/src/routes/api.js b/src/routes/api.js
index d45deee..66cb56d 100644
--- a/src/routes/api.js
+++ b/src/routes/api.js
@@ -169,13 +169,13 @@ router.get('/messages/node/:nodeId', requireAuth, (req, res) => {
 // Send a message
 router.post('/messages/send', requireAuth, async (req, res) => {
   try {
-    const { text, from } = req.body;
+    const { from, text, channel } = req.body;
 
     if (!text) {
       return res.status(400).json({ error: 'Message text required' });
     }
 
-    await mqttClient.sendTextMessage(text, from || 0);
+    await mqttClient.sendTextMessage(from, text, channel);
 
     // Log activity
     logActivity(req.session.userId, 'send_message', text, req.ip);
@@ -224,20 +224,24 @@ router.get('/stats', requireAuth, (req, res) => {
 // Purge old data
 router.post('/purge', requireAuth, (req, res) => {
   try {
-    const { days } = req.body;
-    const daysToKeep = days || 30;
+    const { hours } = req.body;
+    const hoursToKeep = hours || 720; // Default to 30 days (720 hours)
 
-    const messagesDeleted = messageQueries.deleteOldMessages.run(daysToKeep);
-    const positionsDeleted = positionQueries.deleteOldPositions.run(daysToKeep);
-    const telemetryDeleted = telemetryQueries.deleteOldTelemetry.run(daysToKeep);
+    const messagesDeleted = messageQueries.deleteOldMessages.run(hoursToKeep);
+    const positionsDeleted = positionQueries.deleteOldPositions.run(hoursToKeep);
+    const telemetryDeleted = telemetryQueries.deleteOldTelemetry.run(hoursToKeep);
 
     logger.info(`Data purged: ${messagesDeleted.changes} messages, ${positionsDeleted.changes} positions, ${telemetryDeleted.changes} telemetry records`);
 
     // Log activity
+    const timePeriod = hoursToKeep < 24
+      ? `${hoursToKeep} hour${hoursToKeep !== 1 ? 's' : ''}`
+      : `${hoursToKeep / 24} day${hoursToKeep / 24 !== 1 ? 's' : ''}`;
+
     logActivity(
       req.session.userId,
       'purge_data',
-      `Purged data older than ${daysToKeep} days`,
+      `Purged data older than ${timePeriod}`,
       req.ip
     );