I normally use OHP transparencies (acetate) for my PCB masking, but after running out I wanted to find something cheaper (from staples a pack of inkjet transparencies costs approximately £20!). I wanted to try and use paper, since it’s essentially free (everyone has it) and I wouldn’t have to go out and buy more stuff!
I am about to try PikLab with SDCC (Both available via Synaptic Package Manager) and an ICD2. To install the IDC2 I followed this tutorial. It’s supposed to be for the Pic Kit 2, but its just about the same for the ICD2. SDCC also requires GPUtils, so install that too.
One problem so far is [...]
I have come to the conclusion that voltage amplifiers are better than charge amplifiers. Equations state that the gain should be the capacitance of the hydrophone divided by the capacitance of the integrating capacitor. When creating two circuits with (about) the same gain, the voltage amplifier always outperforms the charge amplifier.
This could be because of [...]
I have implemented a new microcontroller that has simultaneous sampling and a slightly higher sampling rate. I could then interpolate the data with pretty good results using a simple padding + band pass filtering technique. The higher the SNR the better it worked.
However, I have hit a great big wall. It all [...]
I’ve had a very serious problem recently regarding the long term stability of the NI-4462.
Problem:
Everything works fine for about 20-inf secs but then all of a suddent the DAQmxReadAnalogF64 function returns a 1 rather than a 0.
Solution:
The errors were buffer overrun errors (annoying that the 4462 almost always returns 1 as an error. [...]
Got the first incarnation of the Phased array working now. Had a few hiccups along the way, but managed to get most of them sorted. Main problems included not having enough RAM to store a significant amount of data, so I fixed that using a simple compression technique (I say simple, took me [...]
Not tested yet, but here are some images of the finished PCB!
Image 1 img_0002.JPG Image 3 Image 4
Just for future reference (because I always forget), using the naff double sided PCB, 3:30 exposure was enough, but by far and away the most important point was to remember to jam the acetate down to the exposure unit, to the point of stressing the joints. Too many times have I relied on the [...]
Still havent had any time to do anything yet but:
Ive decided to run multiple IR modules off one 18F pic then:
I can have a proper multi-master I2C configuration which means proper interrupts.
The IR module will now be smaller/cheaper because of the lack of another pic
Could put some extra fuctions on it too, like voltage/current monitoring [...]