Upcoming Cranquis Interview: Submit your questions by July 2 for possible inclusion!
Cranquistador-Hipster check!
Who was “into” Cranquis back before he was really popular? You know, wayyyy back in December of 2011? Back before 11,000 other people had found this blog? Was it YOU?
If so, you probably remember this audio interview that I did with the nimble-fingered hepcats Tymkrs and Whisker over at zombietech.tv. And we couldn’t leave well enough alone, so… we’re doing another interview next week.
Once again, Tymkrs is accepting questions from my readers to be asked and answered “live” during the interview taping. If you have a question (zombie-related or not, medical or otherwise, anonymous is fine too) that you’d like to submit, drop her a line in her ask box here before Midnight CST on Monday July 2. Please include the tag “#cranquis” for easy identification. By submitting your question, you give permission for it to (possibly) be selected by Tymkrs and included in the interview!
Stay tuned for updates on the air-date for the interview.
Dr. Cranquis Reanimated: An Interview
zombietech.tvDr. Cranquis is our guest again and this time we’re celebrating not only 20,000 followers but also his 2nd Tumblr birthday! Happy birthday Dr. Cranquis! We talk about what it takes to be an urgent care clinic doctor, stories from his resident days and even code situations. We cover a bit of discussion on the latest “zombie” news as well. And for those who sent in questions, you got the fast-track, real-time, live-answering from the Doc himself! Oh and if you’ve ever been interested in what kind of interviewer Dr. Cranquis would be, we tackle that too :).
Ok, first things first: No, I don’t sing in this interview. So you can put away those ear plugs.
Had a ton of fun chit-chatting with the Zombietech.tv Dynamic Duo! Hope you enjoy our meandering hour-long discussion.
(And for those of you who haven’t heard the FIRST Zombietech.tv interview, here it is.)
If the shoe fits...
Quick, somebody figure out Cranquis’ identity by his shoe!
Is that the infamous yellow shoe of Cranquis that I see on the bottom of the pic?? ;D
HAH! I see the bumblebee shoes!
ARE THOSE YOUR YELLOW SHOES?!
I dare anyone to claim that my Cranquistadors are not observant people.
Getting a solenoid to pulse!! (Part 2!)
So I’ve been working on trying to get a solenoid valve to turn on and attract a plate above it to simulate a physical pulse as per this circuit:
So I turned the diode around (since I put it in the wrong direction last time). And took away the propeller for the time being. I also changed the biasing resistor to be 100ohms instead of 12k, even with the calculations.
And when I pulsed the resistor against the power rail, I could feel a faint pulse. It is however, much weaker than what I would like it to be.
So now I’ve got to figure out what I can do to make this a stronger pulse.
Here’s a list of the parts that the original board had:
NJU4030BD JRC 6602 chip
C945 G-625 transistor
Momentary switch
505k ohm pot
682J100N capacitor
124J100N capacitor
3 diodes
1M, 4.7M, 2.2M, 750k, 2.2k ohms resistors
@devbisme suggested I give the circuit 18v and that gave me a pulse that worked well! So the circuit seems to be some sort of voltage doubler. And when I got the propeller to bias the transistor - as long as I remembered to connect propeller ground to circuit ground - it WORKS!!
Okay so the key was putting Propeller ground to circuit ground. I think before I put it to the power rail which was why 9v wasn’t doing anything. But now with 9v, it works with everything’s properly connected!
@atdiy/@tymkrs
Getting a solenoid valve to pulse...or not.
So I’ve been working on trying to get a solenoid valve to turn on and attract a plate above it to simulate a pulse as per this circuit:
So I’ve used a 9v battery and an @tautic breadboard power supply both. The pulse generator is a on-off signal from a propeller pin. Here’s a picture of my setup:
So you see the red and green wires from the solenoid. I’ve got a 2n3904 there being biased by the signal from the propeller (yellow wire) going through a protective 12k resistor.
The collector is connected to 5v (or 9v) through a protective diode and the emitter is connected to ground. The solenoid has one end on the power rail and the other end on the collector. This seems a bit strange but I can’t pinpoint what.
When I measured voltage with the 9v battery, even though the battery itself was good (7-8v), at the breadboard, I was measuring something like…0.5v across the rails. ???!
Does anyone have any ideas what I may need to do? I have a feeling something is funky with ground but also the measurements that I’m making don’t seem right. And I tried measuring current but got 0 in both cases (and yes, I used the working multimeter :p).
@atdiy/@tymkrs
Onwards and upwards to backplanes!
More functionality! More! So the little led heart I’ve been working on can currently physically show the electrical activity of the heart, but I’d like to be able to have a LCD show what rhythm it is, let people feel what that rhythm feels like, and how it sounds as well (http://forums.parallax.com/showthread.php/148063-MISSING-documented-circuit-setup-for-propeller-audio-output). All of that functionality though won’t be able to fit on a small sized PCB.
So a backplane it is!
Objectives: To incorporate a pulse generator, LCD, heart rate receiver, and audio that can interface with the LED heart PCB.
Attempt 1:
I needed to get a proper symbol for the voltage regulator, add some diode protection and resistor protection for the transistor. I also needed to put the input and output capacitors of the regulator parallel style instead of in series. And clean up how the schematic looked a little bit :)
Attempt 2:
At this point I think we’re verifying voltage and current that this particular solenoid (coil of wire around) and after throwing a busted multimeter against the wall, when the switch is on:
- Voltage: 4-6v
- Current: 32mA
- http://kaizerpowerelectronics.dk/calculators/transistor-base-resistor-calculator/ = resistor of 16.8k ohms
This is what that pulse generator idea is based on:
So! When measured, the current runs at about 0.032A which when the transistor is “fully on”, you can assume about 0.064A. Based on the calculator, that’ll give us base resistor values of 15750 to 7875ohms respectively. So let’s go with a nice medium of 12k ohms.
@atdiy/@tymkrs
