Joseph, There are a few data points that lead to this conclusion...
1. Look at the images on eBay for various PRS-10 and TSD-12 auctions. You will see that they all have the same customer part number 143-44101-xx where xx is 04, 08 or 10. Further, you will find a PRS-10 and a TSD-12 with the exact same customer part number of 143-44101-08. This indicates that the TSD-12 is a "drop-in" replacement for the PRS-10 for that customer. 2. In the timenut's archive, there is a user who has / had both. He reported that the TSD-12 self-reports as a PRS12, and additionally have the same firmware version number. 3. The PRS-10 and TSD-12 are physically and electrically identical based on the various eBay pictures. There are two variations that I see. The first is that on apparently newer devices the back side has four mounting holes not present on the older devices. The second is that on some devices the Cannon connector is on the bottom rather that on the back end. All of the TSD versions (-11 and -12) appear to have the mounting holes. Like the PRS-10, some have the Cannon connector on the back end and some have it on the side. 4. The same user reported that all of the PRS-10 devices he examined had the default locking mode of 1 and the TSD-12 devices had a default locking mode of 3. However, the LM command allows the locking mode to be set, and there is another command that will make that change to the power up state. 5. Since the package is physically identical, the firmware is physically identical, if you look at the service manual, there are not a lot of things that could be changed or omitted. Almost everything is in software, including the 1 pps locking (which hijacks the trim pot to do its dirty work). 6. The only option listed on the SRS site for new devices is an option that has a reduced aging rate (at an extra $495). There could be some other minor options like that, but effectively it appears as if the TSD-12 (or -11) is interchangable with the PRS-10 if the LM command is used to set the default locking mode. Mike >> Or, perhaps not. The two working TSD12s that I see on eBay (apparently >> the same as the PRS-10 except the lock flag is set to 3 instead of 1 >> and >> which can be reset) > Would you elaborate on this? I Googled for TSD12 and except for the > auction listings, found nothing. > Joe Gray > WW5JG -- Best regards, Timenut mailto:time...@metachaos.net _______________________________________________ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.