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:
looking for bias tee help - 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: looking for bias tee help Posted: Thu Aug
03, 2006 9:36 pm
Joined: Wed Oct 27, 2004
We're trying to make a 50 KHz to 3 GHz bias
tee. Here are the specs if anyone can help (for a price, of course).
S21 1dB or less to 3 GHz
S11/S22 1.6:1 or less to 3 GHz
isolation 30dB min
Input power 5 Watts
24V @ 3A
a chassis and pc board already fabbed. The board is FR4, .062 and 1oz
of copper plating. Also using 0.1uF 1206 for the coupling cap. For the
bypass, we're using 1000pF, 0.022uF and 10pf 1206 caps. Where we need
help is selecting the proper inductors, not only for performance and
power, but size. I'm told that we need a number of inductors to cover
about 4 octaves. Inside the chassis, we're limited to 1.2"H X 1.6"L
X .480" depth. Anyone with the proper CAD tools may be able to help.
Project should be in the area of 2-3 hours time. Please let me know
at the earliest if you can help. Thanks in advance.[/code]