diff --git a/lib/www/client/source/src/components/encoder/fixed-string-encoder-field.vue b/lib/www/client/source/src/components/encoder/fixed-string-encoder-field.vue
new file mode 100644
index 0000000..8a2b43b
--- /dev/null
+++ b/lib/www/client/source/src/components/encoder/fixed-string-encoder-field.vue
@@ -0,0 +1,269 @@
+<template>
+  <v-row dense no-gutters>
+
+    <v-col>
+      <slot name="prepend"></slot>
+    </v-col>
+
+    <v-col cols="2">
+      <v-chip v-if="value.item && !readonly"
+        outlined
+        label
+        small
+        :color="colour"
+        :title="description"
+      >{{name}}</v-chip>
+      <v-select v-else-if="items.length && !readonly"
+        label="Item"
+        :items=items
+        v-model="value.item"
+        dense
+        title="Select an item to use as a field"
+      ></v-select>
+    </v-col>
+
+    <v-col>
+      <v-select v-if="type == 'boolean'"
+        label="Condition"
+        :items="[true, false]"
+        v-model="value.when"
+        dense
+        title="Use this configuration only when the value of this item matches the selected state. This allows the user to configure different values for true and false conditions."
+      ></v-select>
+    </v-col>
+
+    <v-col>
+      <v-text-field  v-if="type == 'boolean' || type == 'text'"
+        class="ml-3"
+        dense
+        label="Value"
+        v-model="value.value"
+        title="This literal text will be inserted at the designated position"
+      ></v-text-field>
+      <v-menu v-else-if="type == 'number'"
+        max-width="600"
+        :close-on-content-click="false"
+        offset-y
+      >
+        <template v-slot:activator="{ on, attrs }">
+          <v-chip
+            class="ml-3"
+            small
+            :light="$vuetify.theme.isDark"
+            :dark="!$vuetify.theme.isDark"
+            :color="value.scale_offset != null || value.scale_multiplier != null ? 'primary' : ''"
+            :title="`Number scaling${ value.scale_offset != null ? ('\nOffset: ' + value.scale_offset) : '' }${ value.scale_multiplier != null ? ('\nMultiplier: ' + value.scale_multiplier) : ''}`"
+            v-bind="attrs"
+            v-on="on"
+          >
+            <v-icon small>mdi-ruler</v-icon>
+          </v-chip>
+        </template>
+
+        <v-card rounded outlined>
+          <v-card-text>
+            <v-row dense no-gutters>
+              <v-text-field
+                type="number"
+                dense
+                clearable
+                label="Offset"
+                title="Offset the value by this amount (after scaling)"
+                v-model.number="value.scale_offset"
+              ></v-text-field>
+            </v-row>
+            <v-row dense no-gutters>
+              <v-text-field
+                type="number"
+                dense
+                clearable
+                label="Scale"
+                title="Mutiply the value by this amount (before scaling)"
+                v-model.number="value.scale_multiplier"
+              ></v-text-field>
+            </v-row>
+          </v-card-text>
+        </v-card>
+      </v-menu>
+    </v-col>
+
+    <v-col>
+      <v-text-field
+        class="ml-3"
+        dense
+        label="From"
+        type="number"
+        min="0"
+        v-model.number="value.offset"
+        :readonly="readonly"
+      ></v-text-field>
+    </v-col>
+
+    <v-col>
+      <v-text-field
+        class="ml-3"
+        dense
+        label="Length"
+        type="number"
+        min="0"
+        v-model.number="value.length"
+        :readonly="readonly"
+      ></v-text-field>
+    </v-col>
+
+    <v-col>
+      <v-menu v-if="value.length > 1"
+        max-width="600"
+        :close-on-content-click="false"
+        offset-y
+        :disabled="!(value.length>1)"
+      >
+        <template v-slot:activator="{ on, attrs }">
+          <v-chip
+            class="ml-3"
+            small
+            :light="$vuetify.theme.isDark"
+            :dark="!$vuetify.theme.isDark"
+            title="Text alignment"
+            v-bind="attrs"
+            v-on="on"
+            :disabled="!(value.length>1)"
+          >
+            <v-icon small v-if="value.pad_side=='right'">mdi-format-align-left</v-icon>
+            <v-icon small v-else-if="value.pad_side=='left'">mdi-format-align-right</v-icon>
+            <v-icon small v-else>mdi-format-align-justify</v-icon>
+          </v-chip>
+        </template>
+
+        <v-card rounded outlined>
+          <v-card-text>
+            <v-row dense no-gutters>
+              <v-select
+                label="Alignment"
+                clearable
+                :items='[{text:"Left", value:"right"}, {text:"Right", value:"left"}]'
+                v-model="value.pad_side"
+              ></v-select>
+            </v-row>
+            <v-row dense no-gutters v-if="value.pad_side">
+              <v-text-field
+                dense
+                label="Pad character"
+                title="Fill the width of the field on the opposite side by padding with this character"
+                v-model="value.pad_string"
+              ></v-text-field>
+            </v-row>
+          </v-card-text>
+        </v-card>
+      </v-menu>
+    </v-col>
+
+    <v-col>
+      <slot name="append"></slot>
+    </v-col>
+
+  </v-row>
+
+</template>
+
+<style scoped>
+
+.input {
+  flex: 1 1 auto;
+  line-height: 20px;
+  padding: 8px 0 8px;
+  min-height: 32px;
+  max-height: 32px;
+  max-width: 100%;
+  min-width: 0px;
+  width: 100%;
+}
+
+.input >>> .chunk {
+  padding-inline: 1px;
+  border: 1px solid;
+}
+
+.input >>> .chunk-empty {
+  padding-inline: 1px;
+}
+
+.input >>> .chunk-overlap {
+  padding-inline: 1px;
+  border: 1px solid grey;
+  color: grey;
+}
+</style>
+
+<script>
+export default {
+  name: "DougalFixedStringEncoderField",
+
+  components: {
+  },
+
+  props: {
+    value: Object,
+    properties: Object,
+    colour: String,
+    readonly: Boolean,
+  },
+
+  data () {
+    return {
+    }
+  },
+
+  watch: {
+    "value.value": function (value, old) {
+      if (value != null && String(value).length > this.value.length) {
+        this.value.length = String(value).length;
+      }
+    }
+  },
+
+  computed: {
+
+    field: {
+      get () {
+        return this.value;
+      },
+      set (v) {
+        console.log("input", v);
+        this.$emit("input", v);
+      }
+    },
+
+    item () {
+      return this.properties?.[this.value?.item] ?? {};
+    },
+
+    items () {
+      return Object.entries(this.properties).map(i => ({text: i[1].summary ?? i[0], value: i[0]}))
+    },
+
+    name () {
+      // TODO Use properties[item].summary or similar
+      return this.item?.summary ?? this.value.item ?? "???";
+    },
+
+    type () {
+      return this.item?.type ?? typeof this.value?.item ?? "undefined";
+    },
+
+    description () {
+      return this.item?.description;
+    }
+  },
+
+  methods: {
+    reset () {
+    }
+  },
+
+  mounted () {
+    this.reset();
+  }
+
+}
+</script>
diff --git a/lib/www/client/source/src/components/encoder/fixed-string-encoder-sample.vue b/lib/www/client/source/src/components/encoder/fixed-string-encoder-sample.vue
new file mode 100644
index 0000000..02ac914
--- /dev/null
+++ b/lib/www/client/source/src/components/encoder/fixed-string-encoder-sample.vue
@@ -0,0 +1,351 @@
+<template>
+  <v-input
+    class="v-text-field"
+    :hint="hint"
+    persistent-hint
+    :value="text"
+  >
+    <label
+      class="v-label"
+      :class="[ $vuetify.theme.isDark && 'theme--dark', text && text.length && 'v-label--active' ]"
+      style="left: 0px; right: auto; position: absolute;"
+    >{{ label }}</label>
+    <div class="input" slot="default"
+      v-html="html"
+    >
+    </div>
+    <template slot="append">
+      <v-menu
+        scrollable
+        offset-y
+        :close-on-content-click="false"
+      >
+
+        <template v-slot:activator="{on, attrs}">
+          <v-btn
+            icon
+            v-bind="attrs"
+            v-on="on"
+          >
+            <v-icon title="Configure sample values">mdi-list-box-outline</v-icon>
+          </v-btn>
+        </template>
+
+        <v-card>
+          <v-card-title>Sample values</v-card-title>
+          <v-card-subtitle>Enter sample values to test your configuration</v-card-subtitle>
+
+          <v-divider></v-divider>
+
+          <v-card-text>
+
+            <v-container>
+              <v-row v-for="(prop, key) in properties" :key="key">
+                <template v-if="prop.type == 'boolean'">
+                  <v-col cols="6" align-self="center">
+                    <v-chip
+                      outlined
+                      label
+                      small
+                      :color="getHSLColourFor(key)"
+                      :title="prop.description"
+                    >{{prop.summary || key}}</v-chip>
+                  </v-col>
+                  <v-col cols="6" align-self="center">
+                    <v-simple-checkbox v-model="values[key]"></v-simple-checkbox>
+                  </v-col>
+                </template>
+                <template v-else-if="key != 'text'">
+                  <v-col cols="6" align-self="center">
+                    <v-chip
+                      outlined
+                      label
+                      small
+                      :color="getHSLColourFor(key)"
+                      :title="prop.description"
+                    >{{prop.summary || key}}</v-chip>
+                  </v-col>
+                  <v-col cols="6" align-self="center">
+                    <v-text-field v-if="prop.type == 'number'"
+                      :type="prop.type"
+                      :label="prop.summary || key"
+                      :hint="prop.description"
+                      v-model.number="values[key]"
+                    ></v-text-field>
+                    <v-text-field v-else
+                      :type="prop.type"
+                      :label="prop.summary || key"
+                      :hint="prop.description"
+                      v-model="values[key]"
+                    ></v-text-field>
+                  </v-col>
+                </template>
+              </v-row>
+            </v-container>
+
+          </v-card-text>
+        </v-card>
+
+      </v-menu>
+    </template>
+    <v-icon slot="prepend">mdi-list</v-icon>
+  </v-input>
+</template>
+
+<style scoped>
+
+.input {
+  flex: 1 1 auto;
+  line-height: 20px;
+  padding: 8px 0 8px;
+  min-height: 32px;
+  max-height: 32px;
+  max-width: 100%;
+  min-width: 0px;
+  width: 100%;
+  white-space-collapse: preserve;
+}
+
+.multiline {
+  font-family: mono;
+  white-space: pre;
+  overflow-x: auto;
+  overflow-y: auto;
+}
+
+.multiline >>> .line-number {
+  display: inline-block;
+  font-size: 75%;
+  width: 5ex;
+  margin-inline-end: 1ex;
+  text-align: right;
+  border: none;
+  position: relative;
+  top: -1px;
+}
+
+.input, .multiline >>> .chunk-field {
+  padding-inline: 1px;
+  border: 1px solid;
+}
+
+.input, .multiline >>> .chunk-fixed {
+  padding-inline: 1px;
+  border: 1px dashed;
+}
+
+.input, .multiline >>> .chunk-empty {
+  padding-inline: 1px;
+}
+
+.input, .multiline >>> .chunk-overlap {
+  padding-inline: 1px;
+  border: 1px solid grey;
+  color: grey;
+}
+
+.input >>> .chunk-mismatch {
+  padding-inline: 1px;
+  border: 2px solid red !important;
+}
+
+</style>
+
+<script>
+import { getHSLColourFor } from '@/lib/hsl'
+
+export default {
+  name: "DougalFixedStringEncoderSample",
+
+  components: {
+  },
+
+  mixins: [
+    {
+      methods: {
+        getHSLColourFor
+      }
+    }
+  ],
+
+  props: {
+    properties: { type: Object, default: () => ({}) },
+    fields: { type: Array, default: () => [] },
+    values: { type: Object, default: () => ({}) },
+    readonly: Boolean,
+    label: String,
+    hint: String,
+  },
+
+  data () {
+    return {
+    }
+  },
+
+  computed: {
+
+    chunks () {
+      const properties = this.properties;
+      const fields = this.fields;
+      const values = this.values;
+      const str = "";
+      const chunks = [];
+
+      for (const field of fields) {
+        const value = this.fieldValue(properties, field, values);
+
+        if (value != null) {
+          const chunk = {
+            start: field.offset,
+            end: field.offset + field.length - 1,
+            colour: this.getHSLColourFor(field.item),
+            class: field.item == "text" ? "fixed" : "field",
+            text: value
+          }
+          chunks.push(chunk);
+        }
+      }
+
+      return chunks;
+    },
+
+    text () {
+      return this.sample(this.properties, this.fields, this.values);
+    },
+
+    html () {
+      return this.renderTextLine(this.text);
+    }
+
+  },
+
+  watch: {
+  },
+
+  methods: {
+
+    fieldValue (properties, field, values) {
+      let value;
+
+      if (field.item == "text") {
+        value = field.value;
+      } else if (properties[field.item]?.type == "boolean") {
+        if (values[field.item] === field.when) {
+          value = field.value;
+        }
+      } else {
+        value = values[field.item];
+      }
+
+      if (value != null) {
+
+        if (properties[field.item]?.type == "number") {
+          if (field.scale_multiplier != null) {
+            value *= field.scale_multiplier;
+          }
+          if (field.scale_offset != null) {
+            value += field.scale_offset;
+          }
+
+          if (field.format == "integer") {
+            value = Math.round(value);
+          }
+        }
+
+        value = String(value);
+        if (field.pad_side == "left") {
+          value = value.padStart(field.length, field.pad_string ?? " ");
+        } else if (field.pad_side == "right") {
+          value = value.padEnd(field.length, field.pad_string ?? " ");
+        }
+
+        return value;
+      }
+    },
+
+    sample (properties, fields, values, str = "") {
+
+      const length = fields.reduce( (acc, cur) => (cur.offset + cur.length) > acc ? (cur.offset + cur.length) : acc, str.length )
+
+      str = str.padEnd(length);
+
+      for (const field of fields) {
+        //console.log("FIELD", field);
+        const value = this.fieldValue(properties, field, values);
+        if (value != null) {
+          str = str.slice(0, field.offset) + value + str.slice(field.offset + field.length);
+        }
+      }
+
+      return str;
+    },
+
+    /** Return a `<span>` opening tag.
+     */
+    style (name, colour) {
+      return colour
+        ? `<span class="${name}" style="color:${colour};border-color:${colour}">`
+        : `<span class="${name}">`;
+    },
+
+    /** Return an array of the intervals that intersect `pos`.
+     * May be empty.
+     */
+    chunksFor (pos) {
+      return this.chunks.filter( chunk =>
+        pos >= chunk.start &&
+        pos <= chunk.end
+      )
+    },
+
+    /*
+     * Algorithm:
+     *
+     * Go through every character of one line of text and determine in which
+     * part(s) it falls in, if any. Collect adjacent same parts into <span/>
+     * elements.
+     */
+    renderTextLine (text) {
+      const parts = [];
+
+      let prevStyle;
+
+      for (const pos in text) {
+        const chunks = this.chunksFor(pos);
+        const isEmpty = chunks.length == 0;
+        const isOverlap = chunks.length > 1;
+        const isMismatch = chunks[0]?.text &&
+          (text.substring(chunks[0].start, chunks[0].end+1) != chunks[0].text);
+
+        const style = isEmpty
+          ? this.style("chunk-empty")
+          : isMismatch
+            ? this.style("chunk-mismatch", chunks[0].colour)
+            : isOverlap
+              ? this.style("chunk-overlap")
+              : this.style("chunk-"+chunks[0].class, chunks[0].colour);
+
+        if (style != prevStyle) {
+          if (prevStyle) {
+            parts.push("</span>");
+          }
+          parts.push(style);
+        }
+        parts.push(text[pos]);
+        prevStyle = style;
+      }
+
+      if (parts.length) {
+        parts.push("</span>");
+      }
+
+      return parts.join("");
+    },
+
+  },
+
+  mounted () {
+  }
+
+}
+</script>
diff --git a/lib/www/client/source/src/components/encoder/fixed-string-encoder.vue b/lib/www/client/source/src/components/encoder/fixed-string-encoder.vue
new file mode 100644
index 0000000..f38fd11
--- /dev/null
+++ b/lib/www/client/source/src/components/encoder/fixed-string-encoder.vue
@@ -0,0 +1,307 @@
+<template>
+  <v-card flat elevation="0">
+    <v-card-title v-if="title">{{ title }}</v-card-title>
+    <v-card-subtitle v-if="subtitle">{{ subtitle }}</v-card-subtitle>
+    <v-card-text>
+      <v-form>
+
+<!-- Sample text -->
+
+        <dougal-fixed-string-encoder-sample
+          :label="label"
+          :hint="hint"
+          :properties="properties"
+          :fields="fields"
+          :values.sync="values"
+        ></dougal-fixed-string-encoder-sample>
+
+<!-- Fields -->
+
+        <v-container>
+
+          <v-row no-gutters class="mb-2">
+            <h4>Fields</h4>
+          </v-row>
+
+          <dougal-fixed-string-encoder-field v-for="(field, key) in fields" :key="key"
+            v-model="fields[key]"
+            :properties="properties"
+            :colour="getHSLColourFor(field.item)"
+            :readonly="readonly"
+          >
+            <template v-slot:append v-if="editableFieldList && !readonly">
+              <v-btn
+                class="ml-3"
+                fab
+                text
+                small
+                title="Remove this field"
+              >
+                <v-icon
+                  color="error"
+                  @click="removeField(key)"
+                >mdi-minus</v-icon>
+              </v-btn>
+            </template>
+          </dougal-fixed-string-encoder-field>
+
+          <v-row no-gutters class="mb-2" v-if="editableFieldList && !readonly">
+            <h4>Add new field</h4>
+          </v-row>
+
+          <dougal-fixed-string-encoder-field v-if="editableFieldList && !readonly"
+            v-model="newField"
+            :properties="properties"
+            :colour="getHSLColourFor(newField.item)"
+          >
+            <template v-slot:prepend>
+              <v-btn v-if="isFieldDirty(newField)"
+                top
+                text
+                small
+                title="Reset"
+              >
+                <v-icon
+                  color="warning"
+                  @click="resetField(newField)"
+                >mdi-backspace-reverse-outline</v-icon>
+              </v-btn>
+            </template>
+            <template v-slot:append>
+              <v-btn
+                class="ml-3"
+                fab
+                text
+                small
+                title="Add field"
+                :disabled="isFieldValid(newField) !== true"
+              >
+                <v-icon
+                  color="primary"
+                  @click="addField(newField)"
+                >mdi-plus</v-icon>
+              </v-btn>
+            </template>
+          </dougal-fixed-string-encoder-field>
+
+        </v-container>
+
+
+
+      </v-form>
+    </v-card-text>
+    <v-card-actions>
+    </v-card-actions>
+  </v-card>
+</template>
+
+<style scoped>
+
+.input {
+  flex: 1 1 auto;
+  line-height: 20px;
+  padding: 8px 0 8px;
+  min-height: 32px;
+  max-height: 32px;
+  max-width: 100%;
+  min-width: 0px;
+  width: 100%;
+}
+
+.input, .multiline >>> .chunk-field {
+  padding-inline: 1px;
+  border: 1px solid;
+}
+
+.input, .multiline >>> .chunk-fixed {
+  padding-inline: 1px;
+  border: 1px dashed;
+}
+
+.input, .multiline >>> .chunk-empty {
+  padding-inline: 1px;
+}
+
+.input, .multiline >>> .chunk-overlap {
+  padding-inline: 1px;
+  border: 1px solid grey;
+  color: grey;
+}
+
+.input >>> .chunk-mismatch {
+  padding-inline: 1px;
+  border: 2px solid red !important;
+}
+</style>
+
+<script>
+import { getHSLColourFor } from '@/lib/hsl'
+import DougalFixedStringEncoderField from './fixed-string-encoder-field'
+import DougalFixedStringEncoderSample from './fixed-string-encoder-sample'
+
+export default {
+  name: "DougalFixedStringEncoder",
+
+  components: {
+    DougalFixedStringEncoderField,
+    DougalFixedStringEncoderSample
+  },
+
+  mixins: [
+    {
+      methods: {
+        getHSLColourFor
+      }
+    }
+  ],
+
+  props: {
+    properties: { type: Object },
+    fields: { type: Array },
+    values: { type: Object },
+    editableFieldList: { type: Boolean, default: true },
+    readonly: Boolean,
+    title: String,
+    subtitle: String,
+    label: String,
+    hint: String,
+  },
+
+  data () {
+    return {
+      //< The reason for not using this.text directly is that at some point
+      //< we might extend this component to allow editing the sample text.
+      text_: "",
+      //< The value of a fixed string that should be always present at a specific position
+      fixedName: "",
+      fixedOffset: 0,
+      //< The name of a new field to add.
+      fieldName: "",
+      newField: {
+        item: null,
+        when: null,
+        offset: null,
+        length: null,
+        value: null,
+        pad_side: null,
+        pad_string: null
+      }
+    }
+  },
+
+  computed: {
+
+    chunks () {
+      const properties = this.properties;
+      const fields = this.fields;
+      const values = this.values;
+      const str = "";
+      const chunks = [];
+
+      for (const field of fields) {
+
+        //console.log("FIELD", structuredClone(field));
+        //console.log("VALUES DATA", values[field.item]);
+        let value;
+
+        if (field.item == "text") {
+          value = field.value;
+        } else if (properties[field.item]?.type == "boolean") {
+          if (values[field.item] === field.when) {
+            value = field.value;
+          }
+        } else {
+          value = values[field.item];
+        }
+
+        if (value != null) {
+
+          value = String(value);
+          if (field.pad_side == "left") {
+            value = value.padStart(field.length, field.pad_string);
+          } else {
+            value = value.padEnd(field.length, field.pad_string);
+          }
+
+          const chunk = {
+            start: field.offset,
+            end: field.offset + field.length - 1,
+            colour: this.getHSLColourFor(field.item),
+            class: field.item == "text" ? "fixed" : "field",
+            text: value
+          }
+
+          //console.log("CHUNK", chunk);
+          chunks.push(chunk);
+
+        }
+
+      }
+
+      return chunks;
+    },
+
+    html () {
+      return this.renderTextLine(this.sample(this.properties, this.fields, this.values));
+      //return this.sample(this.properties, this.fields, this.values);
+    }
+
+  },
+
+  watch: {
+  },
+
+  methods: {
+
+    isFieldDirty (field) {
+      return Object.entries(field).reduce( (acc, cur) => cur[1] === null ? acc : true, false );
+    },
+
+    isFieldValid (field) {
+      if (!field.item) return "Missing item";
+      if (typeof field.offset !== "number" || field.offset < 0) return "Missing offset";
+      if (typeof field.length !== "number" || field.length < 1) return "Missing length";
+      if (!this.properties[field.item]) return "Unrecognised property";
+      if (this.properties[field.item].type == "text" && !field.value?.length) return "Missing value";
+      if (this.properties[field.item].type == "boolean" && !field.value?.length) return "Missing value (boolean)";
+      if(!!field.pad_side && !field.pad_string) return "Missing pad string";
+
+      return true;
+    },
+
+    resetField (field) {
+      field.item = null;
+      field.when = null;
+      field.offset = null;
+      field.length = null;
+      field.value = null;
+      field.pad_side = null;
+      field.pad_string = null;
+
+      return field;
+    },
+
+    addField (field) {
+      if (this.isFieldValid(field)) {
+        const fields = structuredClone(this.fields);
+        fields.push({...field});
+        this.resetField(field);
+        console.log("update:fields", fields);
+        this.$emit("update:fields", fields);
+      }
+    },
+
+    removeField (key) {
+      console.log("REMOVE", "update:fields", key, this.fields);
+      const fields = structuredClone(this.fields);
+      fields.splice(key, 1);
+      this.$emit("update:fields", fields);
+    },
+
+  },
+
+  mounted () {
+  }
+
+}
+</script>
diff --git a/lib/www/client/source/src/components/project-settings/online-line-name-format.vue b/lib/www/client/source/src/components/project-settings/online-line-name-format.vue
index dfd95ec..03efedc 100644
--- a/lib/www/client/source/src/components/project-settings/online-line-name-format.vue
+++ b/lib/www/client/source/src/components/project-settings/online-line-name-format.vue
@@ -4,20 +4,16 @@
     <v-card-subtitle>Line name decoding configuration for real-time data</v-card-subtitle>
     <v-card-text>
       <v-form>
-        <v-text-field
-          label="Example file name"
-          hint="Enter the name of a representative file to make it easier to visualise your configuration"
-          persistent-hint
-          v-model="cwo.lineNameInfo.example"
-        ></v-text-field>
-
-        <dougal-fixed-string-decoder
+        <dougal-fixed-string-encoder
           title="Line name format"
           subtitle="Format of line names as configured in the navigation system"
+          label="Example line name"
+          hint="Visualise your line name configuration with example values"
           :multiline="true"
-          :text="cwo.lineNameInfo.example"
-          :fields="cwo.lineNameInfo.fields"
-        ></dougal-fixed-string-decoder>
+          :properties="properties"
+          :fields.sync="fields_"
+          :values.sync="values_"
+        ></dougal-fixed-string-encoder>
       </v-form>
     </v-card-text>
     <v-card-actions>
@@ -50,16 +46,19 @@
 
 <script>
 import { deepSet } from '@/lib/utils';
-import DougalFixedStringDecoder from '@/components/decoder/fixed-string-decoder';
+import DougalFixedStringEncoder from '@/components/encoder/fixed-string-encoder';
 
 export default {
   name: "DougalProjectSettingsOnlineLineNameFormat",
 
   components: {
-    DougalFixedStringDecoder
+    DougalFixedStringEncoder
   },
 
   props: {
+    fields: Array,
+    values: Object,
+    properties: Object,
     value: Object
   },
 
@@ -68,53 +67,27 @@ export default {
     }
   },
 
+  watch: {
+  },
+
   computed: {
-    // Current working object.
-    // A shortcut so we don't have to specify the full path
-    // on every input control. It also makes it easier to
-    // change that path if necessary. Finally, it ensures that
-    // the properties being modified are always available.
-    cwo: {
 
+    fields_: {
       get () {
-        if (this.value) {
-          if (!this.value?.online?.line) {
-            deepSet(this.value, [ "online", "line" ], {
-              lineNameInfo: {
-                example: "",
-                fields: {
-                  line: {
-                    length: 4,
-                    type: "int"
-                  },
-                  sequence: {
-                    length: 3,
-                    type: "int"
-                  },
-                  incr: {
-                    length: 1,
-                    type: "bool"
-                  },
-                  attempt: {
-                    length: 1,
-                    type: "int"
-                  }
-                }
-              }
-            });
-          }
-          return this.value.online.line;
-        } else {
-          return {};
-        }
+        return this.fields;
       },
-
       set (v) {
-        if (this.value) {
-          deepSet(this.value, [ "online", "line" ], v);
-        }
+        this.$emit("update", structuredClone({values: this.values, fields: v}));
       }
+    },
 
+    values_: {
+      get () {
+        return this.values;
+      },
+      set (v) {
+        this.$emit("update", structuredClone({values: v, fields: this.fields}));
+      }
     }
   },
 
diff --git a/lib/www/client/source/src/views/ProjectSettings.vue b/lib/www/client/source/src/views/ProjectSettings.vue
index 627f733..6a47384 100644
--- a/lib/www/client/source/src/views/ProjectSettings.vue
+++ b/lib/www/client/source/src/views/ProjectSettings.vue
@@ -67,6 +67,7 @@
           :is="activeComponent"
           v-bind="activeValues"
           v-model.sync="configuration"
+          @update="activeUpdateHandler"
           @close="deselect"
         ></component>
       </v-col>
@@ -279,6 +280,7 @@ export default {
   data () {
     return {
       configuration: null,
+      settings: null,
       active: [],
       open: [],
       files: [],
@@ -420,8 +422,17 @@ export default {
           id: "line_name_format",
           name: "Line name format",
           values: (obj) => ({
-            lineNameInfo: obj?.online?.line?.lineNameInfo
-          })
+            fields: this.makeSection(obj, "online.line.lineNameBuilder.fields", []),
+            values: this.makeSection(obj, "online.line.lineNameBuilder.values",
+              Object.fromEntries(
+                Object.keys(this.settings.lineNameBuilder.properties ?? {}).map( k => [k, undefined] ))),
+            properties: this.settings.lineNameBuilder.properties ?? {}
+          }),
+          update: (obj) => {
+            const configuration = structuredClone(this.configuration);
+            deepSet(configuration, ["online", "line", "lineNameBuilder"], obj);
+            this.configuration = configuration;
+          }
         },
         {
           id: "planner_settings",
@@ -518,6 +529,12 @@ export default {
         this.activeItem.values(this.configuration);
     },
 
+    activeUpdateHandler () {
+      return this.activeItem?.update ?? ((obj) => {
+        console.warn("Unhandled update event on", this.activeItem?.id, obj);
+      })
+    },
+
     surveyState: {
       get () {
         return !this.configuration?.archived;
@@ -559,6 +576,35 @@ export default {
 
   methods: {
 
+    makeSection (obj, path, defaultVaue) {
+
+      function reduced (obj = {}, path = []) {
+        return path.reduce( (acc, cur) =>
+          {
+            if (!(cur in acc)) {
+              acc[cur] = {} ;
+            };
+            return acc[cur]
+          }, obj);
+      }
+
+      if (!obj) {
+        obj = {};
+      }
+
+      if (typeof path == "string") {
+        path = path.split(".");
+      }
+
+      let value = reduced(obj, path);
+
+      const key = path.pop();
+      if (!Object.keys(value ?? {}).length && defaultVaue !== undefined) {
+        reduced(obj, path)[key] = defaultVaue;
+      }
+      return reduced(obj, path)[key];
+    },
+
     async getConfiguration () {
       this.configuration = null;
       const url = `/project/${this.$route.params.project}/configuration`;
@@ -571,6 +617,21 @@ export default {
       this.dirty = false;
     },
 
+    async getSettings () {
+      this.settings = null;
+      let url = `/project/${this.$route.params.project}/linename/properties`;
+      const init = {
+        headers: {
+          "If-None-Match": "" // Ensure we get a fresh response
+        }
+      };
+      this.settings = {
+        lineNameBuilder: {
+          properties: await this.api([url, init])
+        }
+      };
+    },
+
     makeTree (obj, id=0) {
       const isObject = typeof obj === "object" && !Array.isArray(obj) && obj !== null;
       return isObject
@@ -681,6 +742,7 @@ export default {
   },
 
   async mounted () {
+    this.getSettings();
     this.getConfiguration();
   },