Items being re-used are marked with an asterisk.
- Raspberry Pi 3 to run the Bells software. *
- Rapberry Pi Zero to run the MP3 Player in the Nave.
- 2-off Pimoroni Pirate Audio 3 W Amplifier HATs to process and amplify the audio.
- 2-off loudspeakers in the Tower for the Bells. * These will be reconfigured so that instead of being connected in parallel, they will each be connected to one of the Stereo O/Ps of the Bells Pirate Audio.
- 2-off Speakers in the Nave for the MP3 Player. One of these will be the existing speaker * and the other will be a new one. They will each be connected to one of the Stereo O/Ps of the Bells Pirate Audio.
- EW-7318USg USB / WiFi Adaptor with detachable Antenna.
- 6 m coaxial RF extension lead. The Antenna will be removed from the Adaptor and located in the Bell Tower or on the roof and connected to the Adaptor with the RF extension.
- Edimax EU-4208 USB / Ethernet Adaptor.
- Short Cat 5 Ethernet cable. The two Pis will be networked together and the Pi 3 will be configured to route traffic on Eth0 to and from WiFi0.
- 2-off GPIO breakout Boards to allow access to GPIO pins when the Pirate Audio HATs are fitted. (See Note.)
- Quarterjack assembly. *
- 2-off MOSFET drivers for the Quarterjack.
- 12 V to 5 V DC / DC Converter. It may be that only one will be needed, but with the Pirate Audio HATs running off 5 V instead of 12 V as the current system uses, then this is unlikely.
- 12 V PSU or external source. Current requirements are likely to be of the order of 3 to 5 A.
- PSU filter circuit.
- Equipment Case for the above.
- Fan(s) if required.
I am still thinking about how to provide control of the Players and signals to trigger the Quarterjack MOSFETs. I will definitely need to provide two GPIO outputs for the Quarterjack MOSFETs, but the other functions (Next MP3 Track, Wedding March, Late Hours etc), could be triggered using a Webserver in a similar manner to the Engineering GUI currently in use on the River System. I'm open to suggestions, but it would greatly simpilify the hardware if we could lose the toggle switches, which i don't think were used a lot anyway and had real problems with bounce.
Please let me have your comments.