looking for bias tee help - RF Cafe Forums
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Post subject: looking for bias tee help Posted: Thu Aug 03, 2006 9:36 pm
Joined: Wed Oct 27, 2004 4:56 pm
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
RF/DC isolation 30dB min
Input power 5 Watts
24V @ 3A
We have 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]