Add circuit schematics for all hardware revisions

Export PDF schematics to PNG for RS-UV3 Rev C, Rev D, RS-UV3A
Rev A, and RS-UVPA Rev E. Ordered chronologically (C→D→A).
New reference/schematics page with sidebar navigation.

astro.config.mjs

@@ -62,6 +62,7 @@ export default defineConfig({
 							],
 						},
 						{ label: 'Connectors', slug: 'reference/connectors' },
+						{ label: 'Schematics', slug: 'reference/schematics' },
 						{ label: 'Hardware Revisions', slug: 'reference/hardware-revisions' },
 					],
 				},

src/content/docs/reference/schematics.md

@@ -0,0 +1,64 @@
+---
+title: Schematics
+description: Circuit schematics for RS-UV3 transceiver revisions and RS-UVPA power amplifier
+---
+
+Circuit schematics for each RS-UV3 hardware revision and the RS-UVPA power amplifier. Each schematic is two pages — the main transceiver circuit and the power/filtering section.
+
+:::tip[Full Resolution]
+Right-click any schematic and select "Open image in new tab" to view at full resolution for reading component values.
+:::
+
+## RS-UV3 Rev C
+
+First revision with LED indicators and sub-receiver RF output header (S_RX).
+
+### Page 1 — Main Circuit
+
+![RS-UV3 Rev C schematic page 1](../../../assets/schematics/rs-uv3-rev-c-schematic_001.png)
+
+### Page 2 — Power & Charging
+
+![RS-UV3 Rev C schematic page 2](../../../assets/schematics/rs-uv3-rev-c-schematic_002.png)
+
+---
+
+## RS-UV3 Rev D
+
+Includes battery charge management (MCP73213), 8.4V dual-cell LiPo support, and external FTDI serial.
+
+### Page 1 — Main Circuit
+
+![RS-UV3 Rev D schematic page 1](../../../assets/schematics/rs-uv3-rev-d-schematic_001.png)
+
+### Page 2 — Power & Charging
+
+![RS-UV3 Rev D schematic page 2](../../../assets/schematics/rs-uv3-rev-d-schematic_002.png)
+
+---
+
+## RS-UV3A Rev A (Current)
+
+The latest revision featuring on-board USB, buck-boost DC-DC converter, and 3.5V–16V input range.
+
+### Page 1 — Main Circuit
+
+![RS-UV3A Rev A schematic page 1](../../../assets/schematics/rs-uv3a-rev-a-schematic_001.png)
+
+### Page 2 — Power & Filtering
+
+![RS-UV3A Rev A schematic page 2](../../../assets/schematics/rs-uv3a-rev-a-schematic_002.png)
+
+---
+
+## RS-UVPA Rev E — Power Amplifier
+
+5W power amplifier companion board with LNA preamplifier and SWR protection.
+
+### Page 1 — Amplifier Circuit
+
+![RS-UVPA Rev E schematic page 1](../../../assets/schematics/rs-uvpa-rev-e-schematic_001.png)
+
+### Page 2 — Filtering & Control
+
+![RS-UVPA Rev E schematic page 2](../../../assets/schematics/rs-uvpa-rev-e-schematic_002.png)