Add new device page for Radtel RT-4D

Author: marcoSchr

_media/rt4d_back.jpg

@@ -119,6 +119,7 @@ words:
   - tinyuf
   - otadata
   - ffat
+  - Radtel
 patterns:
   - name: markdown_code_block
     pattern: /^\s*```[\s\S]*?^\s*```/gm

_media/rt4d_front.jpg

@@ -25,3 +25,4 @@ This table provides a glance on the underlying hardware of each of the supported
 * [Ailunce HD1](hardware/hd1.md)
 * [Anytone UV878](hardware/uv878.md)
 * [LILYGO T-TWR Plus](hardware/ttwrplus.md)
+* [Radtel RT-4D](hardware/rt4d.md)

cspell.yaml

@@ -0,0 +1,20 @@
+# Radtel RT-4D
+
+## Specifications
+* MCU: AT32F423CCT7
+* DMR Chip: HF6853
+* FM Broadcast Receiver Chip: BK1080
+* Radio Chip: BK4819
+* SPI Flash: PY25Q128HA 16MiB
+* Display: 128x64 monochrome TFT
+* 0x2800 Byte Bootloader
+
+## Pictures
+
+### PCB Front
+
+![RT-4D PCB Front](../_media/rt4d_front.jpg)
+
+### PCB Back
+
+![RT-4D PCB Back](../_media/rt4d_back.jpg)