Thursday, November 26, 2015

Building my own AZ/EL Controller (Part IV)

The Yocto-3D can be split apart.  Where the actual sensor bits (in the 'head') can be physically 'cut-off' the 'base'.  According to yoctopuce they indicate that this 'head' can be as far away as 2-3 meters.  This is good!  This means I can mount the sensor up on the array/antenna-boom and simply run a good shielded 4-wire combo from the sensor (head) to the base.  Instead of having to expose a USB cable to the elements and RF of the array.

I decided to use CAT6 for the 4-wire.  (Cat 6 uses 4-pair [8-wires]) but I'm just going to use 4 of the 8 wires between the head and the base.  

The base will then be mounted down the tower a ways along with the Yocto-Ethernet (USB-Hub).  Then a full CAT6 will run down the tower into the shack with Ethernet from the hub.

So today I decided to get started on splitting and 'housing' the Sensor from the base.  Tomorrow I think (Friday) a NEMA-4 weather-proof steel box will arrive and I'll begin prepping that to house the Yocto-Ethernet and the Yocto-3D "base".  As well as the 2 CAT6 port holes.

So here are some photo's of the housing I've going to try to use (at least the first round).  I opted to use PVC because it's easy to work with.  I will likely paint this with a non-metalic content paint once it's all done.

I used at the 'head' of the sensor housing a PVC screw cap, and at the butt end a simple cap.  The butt-cap has a Water Tight Cable Grip for the CAT6 to go through.

I wanted all of this to be modular.  In case any one 'bit' gets hosed/damaged, I wanted to be able easily replace things without a lot of rebuilding. (hence the screw cap on the sensor housing.

I used RJ45-Adapter to 8 pin screw-down blocks and Picoflex connectors on the "base" and "Head" of the sensor.  I also tested the RJ45-Adapter prior to splitting the head from the base to make sure no metals in it would affect the compass part of the sensor.  And unless it was within about 1/2 inch of the front of the sensor I noticed no deflection of the compass so I think I'm good on that.  The Picoflex 4-wire flat cable is about 4 inches long so that gets the RJ45-Adapter well away from the 'head'.

Here are some pictures of the construction.  Notice that the head and RJ-45-adapter are phyically connected to the 1.5 inch screw cap (using Plastic's Epoxy by Locktite and a 1 inch pvc pipe cut to suite everything.  It's pretty cool how well it came out.

These are all pretty much in reverse order of how construction went.  I'm too lazy today to reorder them, so skip to the bottom and scroll UP if you want to see time order properly.