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+DART-70
+=======
+
+In 2023, the 70MHz band became accessible to amateurs in Switzerland. This offers an excuse to build a transciever.
+
+* Separate things a bit more than on Picardy 2020
+  * One HF SSB/CW exciter PCB with:
+    * Voltage regulators
+    * Mic input from Picardy 2020
+    * AGC measurement like Picardy 2020
+    * AGC IF amp better than Picardy 2020
+      * VEXIBITX applies AGC at HF input instead, and uses uBitx amplifiers for IF
+      * uBitx has no AGC
+      * Hybrid Cascode? (Implies IF between 8 and 12 MHz)
+    * Frequency plan:
+      * What HF intermediate frequency?
+        * High-side mixing? need low-pass to reject image, also rejects FMBC
+          * 96MHz oscillator: 26MHz IF
+        * Low-side mixing (kuhne and anglian do that)
+          * 42MHz oscillator: 28MHz IF
+          * Prefer, can't be wrong if others do that
+        * Reuse Anglian 3L oscillator from lo_board/lo_board.pro
+      * VFOs Si5351A-B-GT for first two mixers
+    * Mixers (3 needed: VHF, HF, AF)
+      * AF: like VEXIBITX
+      * HF: like uBitx (BAT68-04W ring mixer, see doc/ubitxv6.{txt,pdf})
+      * VHF: MCL RMS-11X (+7dBm LO) or the macom one? (missing from inventory)
+    * XTAL filter QER like uBITX at 11.0592 MHz
+  * One PCB with HF-4m transverter, inspired by Anglian
+  * One PCB with 4m driver, PA and antenna switching
+    * We are allowed 25W ERP, aim for 10W PEP
+    * BCW71 driver, 2SCR573D3 push-pull amp?
+    * How about STN4NF20L?
+    * LNA: SPF5189Z
+  * One PCB for frontend
+    * Connected by cable to the main board
+    * Microcontroller, Display, Encoder
+* Enclosure: Hammond 1411R or 513-0900?
+
+## To order
+
+* Adafruit 292 and an i2c display