- Use a black Sharpie to color the end plate edges and exposed panel openings, make that ugly FR4 fiberglass look nearly like the rest of the beautiful end plate!
- Q: Why must I remove HL2 FB28 to use the HL2+ AK4951 Companion Board? A: FB28 must be removed to disconnect HL2 2.5V supply from VCCIO5. A FB on the Companion Board then connects 3.3V to VCCIO5 instead, which is required by the CB CODEC.
- Companion Board Speaker Output (J5) not working? Thetis for HL2 Band Volts/Dither is CB speaker mute. Checked is enabled, unchecked is disabled.
- Regarding the HL2+ AK4951 Companion Board and HL2 IO Board:
The IO board is general purpose and depends on the programming of its RPi Pico processor. The AK4951 Companion Board Kit implements a dedicated Hardrock-50 amplifier control interface and is also capable of controlling the Icom AH4 ATU. This is not to mention the Mic and Phones jacks, Speaker connector, CW sidetone, and FPGA gateware built-in keyer. The IO board (with the appropriate code) can control the HR-50 as well and if you use it, you would simply not use the CB Kit DB9 cable/connector, power switch/harness/header, and rear end plate. The IO board end plate has no accommodations for these (and has its own DB9). Using the IO board requires using its rear end plate. Other than this, the two (CB and IO) can coexist and be used at the same time. All functions of the HL2+ AK4951 Companion Board remain intact and functional in the presence of the IO Board.