From: Bdale Garbee <bdale@gag.com>
Date: Sun, 7 Sep 2025 22:02:35 +0000 (-0600)
Subject: put my Notebook file in the repo, have git ignore the project.lht file
X-Git-Tag: fab-v1.0p1
X-Git-Url: https://git.gag.com/?a=commitdiff_plain;h=cb908a00f3670f36a2d1516070876c3fbd2d4361;p=hw%2Fteleterra

put my Notebook file in the repo, have git ignore the project.lht file
---

diff --git a/.gitignore b/.gitignore
index 1d702e5..59021a9 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,4 +1,5 @@
 partslist*
+project.lht
 teleterra.cmd
 teleterra.drc
 teleterra.net
diff --git a/Notebook b/Notebook
new file mode 100644
index 0000000..cf4651a
--- /dev/null
+++ b/Notebook
@@ -0,0 +1,31 @@
+2025.08.08
+- looking at 40 pin headers to mate the Pi to TeleTerra.  LCSC C25503140 is
+  0.12 per @ q1.  Would mean 0.1" between boards.
+
+2025.08.10
+- thinking more about how the Pi board would mount.  Don't really want it
+  just cantilevering off the 40 pin header.  Thought about reflow solderable
+  PEM nuts.  They make a metric series, including M2.5 which matches the size
+  of Pi 02W mounting holes.  So, what if we were to put two on the board to
+  support the far side of the board?
+
+  The only challenge is that the heights available in the right range are
+  2mm and 3mm.  With the headers that are on offer for cheap being about 0.1"
+  or 2.54mm thick, I think the idea would be to put in the 3mm ones and the
+  header, then drop the Pi board on, screw it down snugly, then solder in 
+  place on the header where it lands.
+
+  PEM part number SMTSO-M25-3ET, Mouser 153-SMTSO-M25-3ET.  Needs a solder
+  pad 6.2mm diameter with a 4.22mm hole.  datasheet/pemnet/kdata-1901229.pdf
+  It annoys me that they are about 0.59 each at full reel of q1000.  Am I 
+  grossly over-thinking this?  40 solder joints on the header might be enough.
+
+  I probably also need to split up the footprint into three distinct parts to 
+  ensure the SMT shop gets a BOM showing the connector and two PEM nuts as 
+  distinct parts and knows what to install where.  
+
+2025.08.13
+- Amazon carries pre-cut rectangles of double sided foam tape in 2mm and 3mm
+  thickness.  A piece of the 3mm tape would probably work as well or better
+  than standoffs and screws, for a lot less money.
+