Copyright: 1996 - 2024
BSEE - KB3UON
RF Cafe began life in 1996 as "RF Tools" in an AOL screen name web space totaling
2 MB. Its primary purpose was to provide me with ready access to commonly needed
formulas and reference material while performing my work as an RF system and circuit
design engineer. The World Wide Web (Internet) was largely an unknown entity at
the time and bandwidth was a scarce commodity. Dial-up modems blazed along at 14.4 kbps
while tying up your telephone line, and a nice lady's voice announced "You've Got
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My Hobby Website:
Filtering noise in IR headphones - RF Cafe Forums
RF Cafe Forums closed its virtual doors in 2012 mainly due to other social media
platforms dominating public commenting venues. RF Cafe Forums began sometime around
August of 2003 and was quite well-attended for many years. By 2010, Facebook and
Twitter were overwhelmingly dominating online personal interaction, and RF Cafe
Forums activity dropped off precipitously. If the folks at
phpBB would release a version with integrated
sign-in from the major social media platforms, I would resurrect the RF Cafe Forums,
but until then it is probably not worth the effort. Regardless, there are still
lots of great posts in the archive that ware worth looking at.
Below are the old forum threads, including responses to the original posts.
|-- Amateur Radio
Gripes & Humor
-- CAE, CAD, &
Test & Measurement
Post subject: Filtering noise in IR headphones Posted: Thu
Jan 12, 2006 1:08 pm
Hello all, a tricky question:
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)
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.
- hope you know what value and where to put those caps.
4. does your
ir led has enough bias?