Red Pitaya - second test
In August 2015, when I made first tests with my new Red Pitaya I wasn't very satisfied with the measurement results deliverd by the RP. The given maximum bandwidth for triangle and square wave forms wasn't really achievable because the signals measured on PC with the RP scope app as well as on my analog/digital storage scope Philips PM 3250 were seriously distorted.
A couple of month later I verified and modified the test setup:
- Coax cable: Shame on me, I used 75Ω instead of 50Ω cables. The cables are now swapped against new SMA cable.
- The 100Mbit/s switch connecting PC and RP probably was not boosting the performance of the data collection coming back from the RP. Thus I implemented a 1GBit/s switch variant. That was planned anyhow.
- Red Pitaya published an update of their scope/signal generator application, which I installed and used for my second test round.
With these improvements I retested the capability of the RP to produce square and triangle waves up to 10 MHz.
The result: Much, much better this time. The Red Dragonfruit made an excellent impression.
Red Pitaya - first test
My wife !! surprised me with a great birthday present - a Red Pitaya.
Red Pitaya is a linux based, open source powered development board. The hardware (14 bit ! ADC, FPGA and much more goodies), is designed to be able to act as a measurement instrument, - for example an oscilloscope, a function generator, a spectrum analyzer. Wow! And it has potential for many more use cases, since it can be programmed by the user. Read more about this project at the red pitaya homepage.
I will mainly use it as measurement tool for electronic designs, repairs, etc.
The "HP-41CX Repair Project"
01.04.2014
The world most famous and in my opinion best handheld computer in the world was and is the HP-41C/CV/CX of Hewlett-Packard. Build and sold in the 80s it has reached "cult status" and a worldwide community of HP-41 enthusiast are keeping the information about it alive.
I can call a HP-41CX my own, which accompanied me during my studies. It was exactly that what a student needed in the 80s, studying electrical engineering. Together with a Math-Module and a card reader at least the electronical support in the exams was perfect.
After several years passed by without touching the device I found out last week that my beloved HP-41CX was "dead" even though powered up with new batteries. Even worse, after I took out the card eader, I noticed that I could spread the upper and lower cover at the upper part of the hp easily.