Because of the high maintenance needed to monitor and filter spammers from the RF Cafe Forums, I decided that it would
be best to just archive the pages to make all the good information posted in the past available for review. It is unfortunate
that the scumbags of the world ruin an otherwise useful venue for people wanting to exchanged useful ideas and views.
It seems that the more formal social media like Facebook pretty much dominate this kind of venue anymore anyway, so if
you would like to post something on RF Cafe's
page, please do.
Below are all of the forum threads, including all
the responses to the original posts.
Post subject: Filtering noise in IR headphones Posted: Thu Jan 12, 2006 1:08 pm
Hello all, a tricky question:
Instead of using batteries, I want to power a couple of IR headphones with an external source, so they are always on.
Then, when I connect a couple of wires where the batteries were, I get a lot of noise...
I'ver tried filtering (47uF in parallel with 100nF), ferrite, shielding power cable ...
The problem appears when connecting the wires to the battery poles, even if there are the normal batteries there and these wires are connected to no place (open circuit)
I mean, this cables act as an antenna for noise, but how can I solve it??
Post subject: Posted: Wed Mar 08, 2006 10:40 pm
Joined: Wed Mar 08, 2006 8:18 am
i assume when u use the battery the signal is clean but the external source, noise appears.
1. check if is it really a cable that act as an antenna. how? examine the short and long wire if the noise increases in longer wire then the cable is one that adds the noise.
2. what kind of external source? regulated/linear type of power supply, if possible dont use switching.
3. filtering - hope you know what value and where to put those caps.
4. does your ir led has enough bias?