Unanswered Questions
16
votes
0answers
654 views
Analyze My Homebrew Diplexer
I'm in need of a diplexer that'll separate RF signals from a single feedline to two antennas. What I designed and built was a diplexer that would allow ~38 Mhz and below out port 1, with ~38 MHz and ...
8
votes
2answers
496 views
EMI Filtering on LVDS lines
This question is slightly related to: What's radiating on my PCB?
These are Beckhoff's EtherCAT industrial IO modules. Each module is connected to its neighbours by 100mbps LVDS. Each module contains ...
5
votes
0answers
352 views
Name for this type of connector?
Can Anyone help me to identify this board to board connector?
7 springs connector on top and 8 on the bottom.
answer
Found a Korean company producing it. Thanks.
This is the plug on the other ...
5
votes
3answers
184 views
Wheatstone bridge sensitivity and accuracy
From my earlier question I was able to wire up 2 SEN-10245 weight sensors (each forming one half of a wheatstone bridge) with an AD620 InAmp & 47 Ohm resistor (to set the gain to ~1000). I then ...
5
votes
0answers
168 views
Unable to get bootloader working on custom PCB with AT32UC3L
I have designed a PCB for a client recently, everything is fine with the hardware and software (application is working as it is supposed to). Now we are facing the need to update the program inside ...
5
votes
1answer
79 views
Industry standard measure for coaxial cable stiffness?
Is there an industry standard measure for coaxial cable stiffness? By stiffness I mean the spring force experienced when bending or deforming the cable.
In my search for a highly flexible lab test ...
4
votes
1answer
169 views
Safe shutdown/restart Raspberry Pi due to a power loss
I am a total beginner in electronics so I need your advice. Does this simple circuit provide for a safe shutdown, with two super caps of 10F?
(Original image)
4
votes
1answer
217 views
DIY NFC boosting antenna for a mobile device
I am very new to this. I'm a dentist trying to improve client flow in a busy office.
I would like to develop a cheap proof of concept for an NFC enabled client tracking system using a hacked mobile ...
4
votes
0answers
192 views
Arduino to Android serial communication issue
I've been trying to use this serial for android library now, but I can't make it work. I'm trying to run this little program in android:
...
4
votes
2answers
376 views
Why does ADC conversion time vary?
I'm using TI Tiva C TM4C123GH6PM on a Launchpad combined with an AD 9850 DDS to create frequency modulator.
Currently I have an extremely simple program which basically sets up microcontroller's ...
4
votes
0answers
174 views
Simulating a magnetic field in Spice
I am trying to simulate a circuit that involves pickup coils in Spice. How would one simulate the magnetic fields that the pickup coils can sense? Additionally, how would one get a frequency response ...
4
votes
0answers
92 views
Implementation of AES algorithm using Systolic architecture
I need to generate a VLSI Systolic array to implement the AES encryption algorithm with key length of 128 bits. Following are the possible ways :
Systolic for Key expansion
Systolic in MixColumn ...
4
votes
1answer
421 views
SPI Read returns only 0 in slave when I hook up SS to INT
I am coding a SPI slave using a PIC16F877A in CCS C and need to be aware when the SS line (pin 7) goes from high (idle) to low (active) as information from the master is framed as a stream of bytes ...
4
votes
1answer
368 views
Why is the loaded Q of a critically coupled two-resonator circuit approximately equal to 0.707 times the loaded Q of one of its resonators?
From RF Circuit Design by Christopher Bowick (page 32 bottom of the page left column):
The loaded Q of a critically coupled two-resonator circuit is
approximately equal to 0.707 times the loaded ...
4
votes
1answer
315 views
Battery powered sensor node power down circuit
I am using the BQ24079T to control power for a wireless, battery powered sensor node. The MCU will operate in one of two modes: periodic sample mode where it takes sensor readings and then sleeps, or ...
