Makeshift Thermal Chamber

For my senior design project, we’re building an Amateur Radio 15m/10m linear transponder for a CubeSat.  In order to test some of our circuits to see how the frequency drifts with temperature, I took a shot at building a cheap thermal chamber.

Mostly, I just cut a couple holes in the top of a normal cooler and sat a lizard lamp dome with 100W ceramic heater in it.  I did see that the cooler is made out of HDPE and make sure it wasn’t going to melt right off the bat.

After turning it on for the first time with nothing inside the cooler, the maximum temperature seemed to stabilize at around 83° C.  This should be a sufficient high end for the preliminary testing that we’re using it for.

We’ll need to figure out what how we want to do the data acquisition. I was thinking of putting in SMA passthrough and using one of the RTL-SDR devices hooked up to a SBC.  Also the best, cheap way to measure temperature.  I haven’t found any DAQs available that are terribly cheap. I might have to assemble my own.

Replaced the Trackpad in my T440s

The trackpad that came with my Lenovo T440s was having some sticky delayed clicks and it was getting pretty frustrating to use. Pretty disappointed with the soft-button trackpad, I found out that some people had figured out how to adapt the hard-button one.

 

Followed this tutorial and after a slight mishap where I didn’t have the ribbon cable in far enough to the socket, it worked pretty brilliantly. Finally I have proper buttons and no mushy trackpad.

Haven’t updated in a while

Haven’t been fiddling with stuff much recently. Started at UCSC in mid-September and have been settling into the area and commute and school and whatnot.

Did end up messing around with Asterisk one night and was able to get a box up and running that responded to a call with an audio file that I had recorded. There’s definitely a lot more to do with it, and I need to come up with a project idea for it.

I have a few more projects that have been on hold. First off, the satnogs station has been stalled for a bit. Took a while to get the circuit boards from China, had some problems in converting the models to imperial sizes (to use with PVC available here, not just for kicks), and Mike’s 3d printer broke at one point, but we should be up and running on that soon.

In order to hit the ham repeater on campus from my home, I’ll have to build an antenna with some directional gain probably. Will be looking into a simple plan to do that soon.

Voice of Korea

Pulled in some Voice of (North) Korea, a couple nights ago. Definitely had some trouble with fading. It seems that my Tentec 1253 is not terribly frequency stable, and it took some fiddling to attempt to keep the signal in tune. Probably one of the most distinctive things I’ve heard so far, such intense music.

Tried to email a reception report to vok@star-co.net.kp but it seems that that email doesn’t work. Not sure if it ever did. Guess I’ll have to mail one in.

Radio Havana Cuba

Pulled in my first reception of Radio Havana Cuba last night on the TenTec 1253 I just built. Pretty awesome pulling stations with just the dead simple random wire antenna that I’m using.

Also got a very faint Spanish-language numbers station and some very noisy Japanese-language stuff, but they were too faint to record.

Should really figure out a ground wire in this attic, and a better antenna.