Difference between revisions of "Apollo - Development Discussion"
From HPSDRwiki
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The original PDF version of the schematic is here: [[media:Apollo_rev_0.pdf|PDF rev 0 Schematic]]. | The original PDF version of the schematic is here: [[media:Apollo_rev_0.pdf|PDF rev 0 Schematic]]. | ||
| − | + | Three comments: | |
| − | 1) 74HC14 can be used in lieu of 74HC04. The '14 has Schmitt trigger inputs, might help with noise immunity on the control line(s). | + | 1) I beleive the interface is SPI rather than I2C for the TPIC595 latches. |
| + | |||
| + | 2) 74HC14 can be used in lieu of 74HC04. The '14 has Schmitt trigger inputs, might help with noise immunity on the control line(s). | ||
| − | + | 3) 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] | |
Revision as of 13:22, 14 June 2009
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
The original PDF version of the schematic is here: PDF rev 0 Schematic.
Three comments:
1) I beleive the interface is SPI rather than I2C for the TPIC595 latches.
2) 74HC14 can be used in lieu of 74HC04. The '14 has Schmitt trigger inputs, might help with noise immunity on the control line(s).
3) 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]
