Metal Casting

Finally getting ready to go forward with this project.

Plan is to cut up a 22l (5.8 ugl) metal pail and line with two 25mm layers of superwool 607 HT, rigidize this and cover with a couple of layers of clay and zirconia mix. Satanite seems to be popular but not that easy to source here.

A castable refracotory hot-face would have been my first choice, but a bit to costly right now.

I will be melting aluminium with propane for a start and probably not that often so I should get plenty of use out this first furnace, and I can always patch cracks as they develop. So time to quit planning to build a furnace and actually build it….

Stellex mini-Yig control board

Mega 8 controlboard

Finally got around to make a PCB to control the Stellex synthesizers. I got a bit frustrated trying to use KiCAD, placing aribtrary vias is something KiCAD could improve as well as arcs in copper layers. I was going to use eagle, but found http://easyeda.com that worked fine, at least for something this simple.

I am not very found of ”cloud” solutions, but being able to do routing wherever you are is appealing…

The boards are not anything special, just a AVR mega 8 and two voltage regulators. I included points to connect to most unused pins, perhaps I will use this for some more generic tasks as well.

Hopefully I will get the boards today, they are on the way from dirtypcbs with DHL. Shipping is more expensive than the pcbs, but I didn’t want to wait for the HK post shipping…

This is just to get started, future plans include stabilization of the internal 10Mhz reference oscillator with GPS and/or an OCXO.

Stellex mini YIG success!

Finally! After tracking down the final bug I got the Stellex Endwave synthesizer to phaselock.

Next step is to maybe build a bit more standalone solution, currently an ATMEGA8 residing on my STK500 controls the LMX2336 on the synthesizer. I have written a real nice piece of code to control the LMX23*6 family of PLL’s before, but I couldn’t find the source so I borrowed John Miles, KE5FX, code and modified it a bit.

Without his site I would never have been able to get it up and running!

Pictures will follow then I get some more work done.

End goal is a LO for my 10GHz transverter (and perhaps for 24G in the not too distant future…)

Before that I will replace the on-board TCXO with external OCXO.

/SA7AEN

Accessing AVR Dragon as user

If you want to use your dragon without having to use sudo to run avrdude, create a file under ’etc/udev/rules.d’. Call it for example 99-avrdragon.rules

You only need a single line in the file:

SUBSYSTEM==”usb”, ENV{DEVTYPE}==”usb_device”, ATTR{idVendor}==”03eb”, ATTR{idProduct}==”2107″, MODE=”0666″

After that plug in you dragon and try it out!

You could probably be more creative and assign it to some group(perhaps dragonusers…), but this works for me in ubuntu 14.04

2M antenn 4 element

Jag behöver en antenn som är relativt liten och portabel, maxlängd ca 1 meter. Valet föll på en konstruktion från DK7ZB. Den är inte den mest optimala med tanke på gain, men den är bredbandig och bör fungera bra för både SSB och FM. Dessutom så bör den vara ganska förlåtande vid konstruktionen, matchningen blir också lätt.

Statusen är att bommen är borrad, inga element är kapade. Planen var från början att svarva och fräsa fästen av polyamid, men under tiden har jag skaffat en 3D-skrivare så tanken nu printa fästen i nylon och få en ursäkt att lära mig Freecad.