Were they tested sufficiently for radiation resistance? I'm assuming that the tantalum was used to add radiation shielding for things like flash memory on the MCU. Mirek's receiver also uses flash memory to store the frequency. The PLLs used in the existing 70 cm receiver can be purchased in a pin-compatible rad-hard version. However, the frequency has to be stored in flash memory. PIC MCUs hold data for 40 years on earth but space is a harsher environment.
We have the option of buying PLLs (with more pins) that can be hard-wired to a particular frequency. These PLLs are much more expensive and have longer lead times as they are space rated.
----- Original Message ----- From: "Robert McGwier" [email protected] To: "Bill Ress" [email protected] Cc: [email protected] Sent: Thursday, June 14, 2007 10:46 UTC Subject: [eagle] Re: CAN-Do noise abatement plan and questions
That they were not sufficiently tested by anyone who was to use them to build flight units. This consumed tantalum slides, and lots of effort. Stephen got essentially zero feedback from the engineering test units he sent. This noise issue could have easily been found. They have had the engineering units for a LONG time.
Bill Ress wrote:
Just curious - what were the "objections?"
Regards...Bill - N6GHz
Robert McGwier wrote:
The Germans demanded their flight modules over the objections of the designers and manufacturers so they are on their own with the consequences.
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