Apollo - Development Discussion
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The initial Apollo schematic is available for comment and suggestions are desired. Please place them here or email to the mailing list hpsdr@lists.openhpsdr.org or direct email to Kjell Karlsen
October 10, 2009
The New PDF version of the schematic is here: File:Apollo Schematic rev 1A.pdf.
The original PDF version of the schematic is here: PDF rev 0 Schematic.
Three comments:
- I believe the interface is SPI rather than I2C for the TPIC595 latches.
- 74HC14 can be used in lieu of 74HC04. The '14 has Schmitt trigger inputs, might help with noise immunity on the control line(s).
- Suggest considering PIN diode antenna switching instead of a relay (RL15). For those who operate CW QSK, quiet is nice. It's even nice for those who don't :-). KK7P 21:22, 14 June 2009 (UTC)
- Another comment: An Elecraft T-1 could also be accommodated at these power levels as an alternative to the suggested LDG. Disclaimer: I work for Elecraft. KK7P 05:02 31 July 2009 (UTC)