[hpsdr] High Accuracy Timing for HPSDR

[Steven Bible]

Hi Alex,

I'd be willing to help with this board since I was the one that laid out the
Reflock II PCB.

As to a GPS engine, we need to look for a timing GPS.  A timing GPS can
perform a self survey and then lock its position for a more accurate 1PPS
signal.  The older 8-channel Oncode UT, UT+, and VP, or the newer 12-channel
M12, M12+, and M12+ Timing have been timing GPS of choice for hams since we
could buy them and using W2GPS's TAC32 program to operate them.  Since
Motorola sold off its Oncore line to SiRF, and the dust is about to settle,
the M12 line will come out later this year as the M12M.

I have already started on a PCB that integrates the GPS, Reflock II, and 10
MHz OCXO (I am looking at the Crystek CO27VH15DE-12-10.000 available from
Mouser).  The goal I have is to design the board such that all the parts can
be readily purchased.  I really don't want to rely on surplus GPSs and
OCXOs.  This entire lash up will be tested in N8UR's timing lab.  The GPS
footprint would accomidate the Oncore UT/VP and M12 GPSs.  So if you can
populate which ever one you have on hand, or can purchase surplus or a new
M121M.

73,

- Steve, N7HPR
 (n7hpr at tapr.org)



> -----Original Message-----
> From: Alex [mailto:harvilchuck at yahoo.com]
> Sent: Wednesday, May 10, 2006 2:44 PM
> To: hpsdr at hpsdr.org
> Cc: Steven Bible
> Subject: High Accuracy Timing for HPSDR
>
>
> Would it make sense to have a frequency reference board for the HPSDR?
>
> How about an ATLAS version of the Reflock II board with an integrated GPS?
> Say the Sony CXD2956AGL-1 baseband processor and the Sony
> CXA3355TQ downconverter - basically the guts from an OnStar (tm)
> GPS receiver...
>
> CXD2956AGL-1 -
> http://www.sony.co.jp/~semicon/english/img/sony01/a6808473.pdf
> CXA355TQ - http://www.sony.co.jp/~semicon/english/img/sony01/a6807578.pdf
>
> add an appropriate VCXO, put some SMA connectors across the top
> of the card (modifying the TAPR TADD-1 design) to distribute the
> reference signal and  then you've got a necessary building block
> for use by transmitter and receiver board designs ...
>
> Just a bit of circut design to add the new parts, the Altera MAX
> II coding is done for the Reflock II. Will need to add a bit of
> code for the GPS baseband processor control, it looks like there
> are enough I/O lines available on the MAX II (based on the docs
> on CT1DMK's website) unless you let OZY control it. Plus
> interface the MAX II to the OZY.
>
> I could even be persuaded to pony the money up for a couple alpha boards.
>
> Alex, N3NP
>
>
>
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