Hi

The batch I just got in yesterday have a six pin connector on top labeled J2 and a
15 pin connector on the back labeled J1. There is no pin at location 14 on J1. There
is an unpopulated location for a 10 pin J7 (looks like JTAG). There is also a set of
holes in another 10 pin array labeled with “TPxx” numbers on them. There is a six
pin connector labeled J4 on the back side by some switching regulators. Pin 6 is
missing on this one to key it.

There are four coax connectors on the board. J6 is the antenna connector. J9 and
J10 came with coax cables plugged into them. J8 is just sitting there.

The copyright on the board is 2010. The Spansion flash(?) chip has a sticker that
reads 11-1402A2 U10. There is a second chip with a sticker that reads 11-1401A5
U25. All but one of the OCXO’s on mine are CTS 1960017’s. They have date codes
from mid 2010 through 2011. I have one with a Bliley NVG47A1282, it is unclear
how they do date codes. That one might be from 2012. All of them have Furuno
GT-8031G’s on them.

Condition wise, they all look ok. The through hole parts were put on by hand. They
could have done a better job of cleaning up after they did that process. Some of
the slider joints look a bit oxidized as a result of the “no clean” process. SMT stuff
all looks fine to my tired old eyes.

All of the anti-static bags have the same seal sticker on them. It has “Made in Madras,
Oregon, USA    The De Leone Corp ASC #274” (= sticker manufacturer). The bags
themselves are US made by Desco.  They could be original or just what my eBay seller
used to pack and ship.

No idea what any of that means. Good news is that they all appear to have the
same 2011 firmware in them. It is not at all clear where they have been for the last
five or six years. They might be equipment pulls. Based on the nice bags and cables,
I’d bet they sat in a stock room while some obscure company went out of business ….

Bob

Hi

Digging a bit more into this and that:

The board in this writeup:

http://www.qsl.net/wa2omy/A%20Packrat%20GPS%20Receiver%20Project.pdf http://www.qsl.net/wa2omy/A%20Packrat%20GPS%20Receiver%20Project.pdf

Has 2005 firmware in it (6 years before our boards). It was built at the end of 2006 (again about
6 years earlier). The connectors on the board are nothing like the connectors on the
boards I have. No idea when the earlier board was designed, the area that shows that data
on the later board is blank on the earlier board.

It is the same board as shown here in the PackRat stuff:

http://www.packratvhf.com/A%20Packrat%20GPS%20Receiver%20Project.pdf http://www.packratvhf.com/A%20Packrat%20GPS%20Receiver%20Project.pdf

Since the boards (and firmware) are very different, I would be careful about taking all
that is said in the previous write ups as valid. Pretty much everything needs to be checked.
Both the FPGA and the MCU went through major changes between the two boards. The
temperature sensor is very different on the newer design (if it’s even there on the old one ..).
They certainly share a common heritage. There are some major differences ( three coax
outputs vs 2 …missing connectors …..).

Bob

I picked up two of the parent units (the LMU300 19” rack mount chassis) and have also managed to find a copy of the installation document manual (for deployment and installation of the hardware, and system turn up procedures).  It is of limited use since there is very little you can do with the GPS(DO) module besides setting the location and checking satellites. But if you have the chassis and want to play with it contact me off list.

A couple of observations on the LMU300:

• the console port is the AEP port, a 6 pin RJ-11 - and you need a 6 pin connector
• the USB port is non-functional
• pin 1 (furthest left looking into the jack) is ground, pin 1 (furthest right) is LMU300 txd, pin 3 is LMU300 rxd
• 115200,N,8,1 speed and format
• the unit will not boot completely on it’s own due to missing T1/E1 signaling from the SMLC
• the unit will not boot completely without GPS initialization
• both of the above conditions can be bypassed :)
• in spite of the above, both of my units are still unhappy and eventually reboot with watchdog timeouts or other errors

A few notes on the GPSDO module:

• the 5 pin header near U19, the LM74 temp sensor:

  • pin 5 or the third pin in the row closest to U19 is the 12v input (measured). the other 4 are all ground.

• the 15 pin header:

  • pins 1,2,5,6,9,10,13,14 are all ground
  • pins 3 and 4 are 3.3v ttl level, I’m guessing another serial port
  • pins 7 and 8 are 3.3v ttl level, and contain the same data as J2 pin 2
  • pins 11,12 are 1 pps, 10ms, 5v

• the 6 pin header, J2:

  • pin 1,4 are ground
  • pin 2 is output from the module, pin 3 is input?
  • pin 5 may be hardware handshake (like CTS/DSR/DCD)
  • pin 6 looks like the Furuno data - lots of $PFEC strings

• the unused MCX connector is 1pps, 10ms, 5v buffered by 74AC74

• software wise, what I see so far is similar to the Packrat info. $CLOCK, $STATUS messages etc. I did note an $EXTSTATUS message, but that’s the only new thing so far. If i discover anything useful/interesting I’ll send an update.

The GPS engine is a Furuno GT-8031, not sure why it hasn’t been findable but the manual is on KO4BB’s site:
<http://www.ko4bb.com/manuals/71.233.182.39/Furuno_GT8031_Protocol_Specification_Rev1.pdf http://www.ko4bb.com/manuals/71.233.182.39/Furuno_GT8031_Protocol_Specification_Rev1.pdf>

The OCXO on my unit is a CTS 196 series. It’s advertised as ‘low phase noise’. Datasheeet here:
<http://www.xtal.cc/UploadFiles/Product/20161101163222_40783.pdf http://www.xtal.cc/UploadFiles/Product/20161101163222_40783.pdf>

Again, contact me off list and I’ll send the LMU300 doc or a pointer to it.

Paul - K9MR

On 5/9/2017 9:41 AM, Tim Lister wrote:

Hi Tim and list,

I put the scope on mine last night - J9 and J10 are both 10 MHz outputs
and J8 is 1 PPS.

I built my own - had a leftover serial cable from, ironically enough, an
old GPS unit with a DB9 on it and bare wires on the other.  I installed
some 2.54mm crimp connectors onto the bare wires and just plugged it in.

It is full-on RS-232 with real RS-232 signal levels, so don't
accidentally hook it up to TTL-level serial.  I almost did that the
other day in my excitement to get it up and working.

Personally, I wouldn't use the mini-grabbers...but that's just me...

thanks,
ben

On 5/6/2017 8:13 PM, ziggy9+time-nuts@pumpkinbrook.com wrote:

Hi Paul and list,

When you say "pins 3 and 4 are 3.3v ttl level, and contain the same data
as J2 pin 2" does that mean that pins 7 and 8 on on the 15 pin header
are the RX/TX pair TTL side of the SIPEX TTL-to-RS232 chip?
+
One of the things I was hoping for was to find TTL access to the serial
port so I don't have to go Arduino TTL to RS232 off-board and then go
back from RS232 with the Sipex chip on the board.

Have taken a look-see on pins 3 and 4 to see if there is any serial data
coming in / going out of there?

thanks much,
ben

Good evening Paul and list,

So I've been working on the LMU300 tonight.

On 5/6/2017 8:13 PM, ziggy9+time-nuts@pumpkinbrook.com wrote:

I decided to verify that the USB was non-functional...just in case your
unit had an issue.  Wow I wish I had not!  Win7 started to install a
driver, failed to install, then got BSOD.  Reboot...and immediate BSOD.
After about an hour of troubleshooting I determined that somehow, and I
don't know how this could happen, it corrupted the driver of my Prolific
USB-to-Serial converter...as I determined that BSOD only happened when
it was plugged in.  Had to flush out the driver and reload...and now all
is well again.

My LMU300's GPS never gets past the boot screen...but somehow...the GPS
light goes green?  That GPS light must not really be looking at the
GPS...or its more akin to a "GPS board seems present" versus "GPS is
working, seeing satellites, etc..."

Mine is 12VDC as well - right on the money too.  I thought 15 VDC was
odd - the unit has 12VDC fans...why not have one 12 VDC supply and run
both the fans and GPS unit from it?

Does this mean that pins 7 and 8 are a TTL serial RX/TX pair that
function the same as J2...but without going thru the Sipex TTL-to-RS232
converter?  That would be a score for those of us who want to use these
things with Arduinos.

If I get up the courage after my BSOD fun...I may have to try it.

Time to find that disposable laptop I've got somewhere around here...
The LMU300 can BSOD that thing all it wants!  ;)

thanks much,
ben

Evening all,

Got brave and decided to experiment...and answered my own question below...

On 5/9/2017 6:02 PM, Ben Hall wrote:

And the answer is sort of.

What I didn't understand in the original message is that "pins 7 and 8
are 3.3V TTL level" meant that pins 7 and 8 are connected together.

So...

Pin 7 and 8 are connected together...and are TTL serial out.
Pin 3 and 4 are connected together...and are TTL serial in.

My little TTL-to-serial adapter is wired RX to pin 7, ground to pin 5,
TX to pin 3.

There is a catch!  If you've got the jumper on J2 from using a real
RS-232 port...the TTL serial input won't accept commands.  You've got to
remove the jumper.

This makes me happy - those of us who want to use Arduinos now don't
need to mess with going TTL to RS232 serial...can go direct TTL to TTL.

thanks much,
ben