Recent content by spid3rx

Hello all, I'm now working on the 2.45GHz frequency transmission line layout on the PCB. I would like to know whether there is a design guideline for the 1) minimum length of the transmission line. how do I know or calculate? I can calculate the width of the TL to get the 50ohm impedance...

Hello all, I encounter some RF burn issue on the metal contact between an antenna with the grounding. The metal is actually connecting to the ground. I suspect that it could be due to the grounding effect which may be too long or too short for that frequency that is radiating. Because of...

maybe you can just explain how you get the final answer? the picture is quite blur to me ...

0xDEADBEEF No, as of I measured today and tomorrow, I don't get consistent data. I am thinking its due to the equipment thermal. I guess I should have let the equipment to be on for a while to let it stablize the thermal effect. If I attach (measure) and detach and re-attach (remeasure) ...

f95toli Thanks again, I slowly get the idea of the "drift" and should be aware that those thermal is really a nuisance in affecting the result if I am measuring really low resistance with accuracy. The IV measuremetn setup that you mentioned, is it that you are referring that we should have...

From my understanding, for like dipole/monopole antenna, the signal line and the ground line are separated. For DC, it will sees the transducer (antenna) as an open circuit, hence no current flow results no radiation.

thank you all for the comments. I really appreciate the feedbacks. It seems to me even the fundamental measurement requires a lot of in depth understandings. Yes, I suspected the oxidation and thermal, that's why I make a pcb, soldered all the 6 pins together, and make the sensing + probe on the...

Yes, I was suspecting it was trying to correct the resistance value. For the total of 6 pins that I measured, it will drop like from 110mohm to 80+mohm and it takes like 25 mins to reach that. not too sure how is possible to measure fowith that long period of time just for the resistance...

Hello all, I've been trying to measure the resistance of a pin, which the supplier spec at around 15mohms. I am using the hp 34401 multimeter with the 4 wire method to do the measurement. Its seems to me that when I probe the tip and the base of the pin, the resistance value is not...

Sorry, there was a typo there. I was a 2SD2216 transistor.

Hello all, I have been trying to simulate a circuitry involving a transistor for the microphone line. I believe it was used for amplication of the external audio signal (not too sure, maybe can share the circuit). I am using the ADS to simulate my circuit. The problem I faced was the...

its not old radio :) I am not trying to mute the speaker output jack, instead I want the audio. this can be done with the help of the dc block.

Thanks sphiecentaur. The main reason for single ended connection, the audio amplifier sees a low impedance that is going to ground hence causing stress in order to provide higher current. Correct me if I am wrong :) For BTL, even without the DC block, the speaker will work, is it been...

Hello all, This is my first post in this forum. Hope can get some constructive help from the community. I did some testing with some radios which is actually a double ended circuit (BTL), meaning it has the spk+ and spk- port. When I want to connect it as a single ended circuit, meaning...