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Month: December 2018

Rad

Rad

I got a new radiation detector for Christmas. It is a Mazor PRM-9000 with a Halogen quenched pancake flat G-M sensor, which is a bit more sensitive compared to the more common vertical tubes. Compared to my other counters it is second in sensitivity, and has good response to alpha, beta, gamma, and x-rays.

I did some calibrations using my CS-137 source, and took it on a flight to do some measurements.

As expected, you can see the increase in exposed radiation with altitude, as well as the decrease in radiation exposure as we traveled to lower geomagnetic latitudes. The reduction while traveling towards the equator is due to protective qualities of the earth’s magnetic field. ( the field at ther equator is almost perpendicular to cosmic particles, which are mostly protons at >10^8 Mev, so only particles with sufficient energy can pass through).

It is always good to see the data match with the theory. If you don’t test and calibrate a sensor it is just a well formed piece of rock.

House

House

House update – Pouring underway.

This morning we poured the shop floor, the lower rooms, and the upper garage floor. (~70 yards). Tomorrow AM we will pour the lower garage floor.

It will take most of the rest of today to do the finishing work on the floors poured.

The lower garage floor is interesting, as we are using these metal pieces called Combiforms that are laser set to get an exact slope from all four corners into the two drains. They are made by a Swedish company, and are used a bit more in Europe.

This is the 5th day of having a pump truck onsite during the build, so tomorrow should finish out the 6th and final pour, at least until we do flatwork next fall.

House

House

A small house update:

4 of the horizontal beams have been installed and leveled. These beams will support the joists for the upper floors, so they are critical to get installed for framing to start. The bigger rear beams for the back deck are being galvanized, and should be ready for install in a few weeks.

We hope to have a pause in the weather the next few days, long enough for us to pour the lower floors. The concrete guys have setup the screed rails, which is not something I have personally seen before. I believe it makes it easier and faster for them to keep the top final surface level.

They have also installed these small steel dowel bars that go across the area they will cut after the pour. As I understand it they grease one side of the bars, and after the cut this allows the slab to move a little bit and prevent cracking elsewhere. I don’t recall seeing this in my current garage floor, although this is a larger floor with far more rebar.

Hopefully tomorrow we will pour two of the garage floors and the storage room, mechanical room, server room, and vault. This will leave one remaining garage floor for Friday.

BLE

BLE

Has anyone built their own Bluetooth BLE beacon based presence detection system for home automation? Here is what I am thinking:

I want to have my home automation system know what room I am in, and when I go from room to room have that motion tracked and used to allow lights, music, etc to follow me around.

My idea is to put a small Bluetooth BLE beacon node in every room (probably on the ceiling, center of each room), and have those nodes all report back beacon messages to a central server with RSSI and UUID information. The central server could use that data to triangulate the user location and allow the home automation system to take action.

The user could have a small Bluetooth BLE beacon, or alternatively just have a phone and watch that does beacons ( iPhone, Android, Apple Watch, etc).

The triangulation would be a bit more complicated as RSSI varies a great deal based on path, so reflections can add some complexity, however I might be able to use a neural network to learn patterns and make location estimations. This kind of dataset would be a good match for that kind of machine learning.

I could use an ESP32 for the beacon nodes, as they have BLE support, and would be easy to develop for as well as install and power.

GTO

GTO

Some of you might remember me posting a few weeks ago about tracking down a misfire problem in my GTO. I did a new fuel system build, and figured I might have had some contamination in the fuel system (my own fault). I took the opportunity to put new ID1050X injectors in the car while I was digging into it. The new injectors work fine, but the misfire was still present. I took a look at the spark plug and it looked fine, but to be sure I swapped the plug, plug wire, and coil with another cylinder. That had no change, which suggested that perhaps that cylinder either had some internal problem, or was not getting fuel.

I did a quick compression check on that cylinder and it checked out fine. I them remembered that the racelogic traction control system intercepts all 8 fuel injector drivers. When I installed it I did it with the connectors such that it was easy to bypass it. I did the bypass and all 8 cylinders worked great. After a bit more playing around it seems the connector on the Racelogic unit itself is the problem, because I can wiggle it and get it to work. It might be the connector solder joints on the board, so I might just crack the unit open and reflow it.

House

House

House Update – Some of the steel vertical posts were installed today. The second picture which shows the two posts at the very back of the shop give a good idea of how high up the first floor is, and how high the ceiling will be in the shop. It looks taller than it did on paper.

Tomorrow or Friday should bring some of the steel cross members.

A quick fly around:

https://youtu.be/cfqliXcL2hs

Birthday

Birthday

Well, today I celebrate my 48th trip around the big burning ball. It has been a pretty awesome journey so far. I have managed to stay alive, stay out of jail, and make some fantastic friends. I have an awesome family with an awesome daughter who is every bit as quirky as I was at 6.

It is a bit surprising that in all these years I have never been admitted to a hospital, broken any bones, or ever had antibiotics. If there was one thing I would like to do in the next 48 years, it would be to get into space. That would be sweet. Preferably not a one way trip though!

Thank you to all of my friends far and wide. Your friendships both small and large make life full of curiosity and joy.

ESP32

ESP32

It is amazing how far these little ESP32s have come. To think you can buy one for $10 that has wifi, bluetooth, 32MBs of Flash, a display, battery charging, tons of IO including ADC, DACs, UARTS, SPI, and GPIOs.

The Raspberry Pi Zero W has more power of course, but if you want something small and embedded with greater reliability these are so easy to use.

You can even do everything through the Arduino interface and libraries which is super easy to setup and build from.

Oil

Oil

Time for an oil change in this 17 year old Subaru. I really should drive it more.

Who can guess what song I am listening too while doing this? Hint – it was released in August 1981 in the US (album) and as a single in November 1981, and the prologue makes awesome use of a vocoder.

House

House

Progress on the house is slow but steady. All of the foundation gravel backfill is complete, and the concrete guys are back for the 4th pour, the floors. This last pour should be about 80 yards. There are still 4-5 more days of steel rebar installation, then if the weather allows it 1 or 2 days of pour.

Next up after that is structural steel installation.