need help: L-Band active antenna

[kd7rto]

I've got an antenna that was used to provide GPS timing to a ribidium oscillator. On the original equipment, I measured 5 volts DC going to the antenna. I believe this should be suitable for inmarsat, and for generally exploring 1-2 GHz with my AR5000.

My question is what do I need to introduce the dc voltage toward the antenna, and to block it toward the receiver?

[zz0468]

You need a device called a bias tee. You can build one yourself easily enough, or you can throw money at the problem and get one ready made. Mini-Circuits sells some decent ones.

[xz]

Hi,

regarding your antenna, you ned to find a 'power inserter' which will indeed provide a DC + RF path to the antenna and a RF path to the receiver. The GPS antenna will most likely have a narrow filter in it, especially if its from a timing application, this will limit your reception to 1574.42 +- a few MHz. You would be better off getting the original GPS / Rb oscillator and using that if it provides a 10MHz out, to lock the ar5000 to, and then build a wideband LNA for 1 to 2 GHz, there is tonnes of stuff to listen to from space.

regards,

Paul
UHF-Satcom.com - The #1 online resource for VHF to EHF satellite reception and monitoring

[kd7rto]

Originally Posted by xz

there is tonnes of stuff to listen to from space.

"Listen" as in view on a spectrum analyzer, or audio that can be demodulated, and data which can be decoded?

Here's what I am familiar with, that your average joe at home can monitor:

AMSAT and the ISS on ham freqs.

Wefax from NOAA 15, 17, 18 and 19.

FTA and subscription TV on c and ku bands.

Sirius and XM, using proprietary devices.

GPS to commercially available devices.

Pirates on 255.55 and 256.85 MHz.

Inmarsat std-C, with the inmarsatdecoder.com demo program.

In addition, I've picked up signals from Cosmos 2414 on 149.97 MHz, and Cosmos 2429 on 150.03 MHz, but I'm unaware of any method to decode them.

Am I missing anything?