----- Start Original Message ----- Sent: Tue, 10 Jul 2007 22:31:21 -0700 (PDT) From: Ernest Erickson aec9823@yahoo.com To: amsat-bb@amsat.org Subject: [amsat-bb] Re: Source for L-Band Preamplifier and Bias Tee?
Eric:
Try Mini-Circuits for bias Tees.
They are very high quality and very reasonable in price as well.
I believe the address is: www.mini-circuits.com
Give them a call, or Google them, you'll find them quite easily I am certain!
Hello,
I ran across some of their pages on preamplifiers but not bias tees. Thanks! I thought of them more for mixers, mmics and other parts.
Google is a blessing and a curse. I went through 10 pages of search results and came across papers on bias tees, companies that sell 400 GHz Bias Tees for over $1000. etc. Sometimes you need to figure out the right terms to get what you want.
Winradio came through and I am getting a replacement for my preamplifier. I am going to use only the bias tee on it. They have a diode to prevent backfeeding of power from the coaxial jack to the receiver port but leakage current will still cause voltage to build on the receive port with high impedance loads. My AOR AR5000 uses relays connected directly to the antenna port for switching and all the rf front ends use capacitors with no DC path to ground. I suspect that relay switching caused a spike. I gave feedback to WinRadio so they may correct the problem soon.
I am starting to use NEC and to make or modify L-Band antennas so I might as well order some stuff from mini-circuits and make my own preamplifiers as well. In 5 or 6 years I can become a RF Software Consultant. :)
73 Eric