1.2 GHz AV Rx Antenna upgrades?

[henkvdw 0]

I recently got a system similar to this:

http://www.hczye.com/en/product_detail.asp?productid=422

Mine has a 1000 mW Tx that looks exactly the same as the 1500 mW unit in the link.

I'd like to upgrade the Rx antenna with something like this:

http://www.l-com.com/item.aspx?id=20248

When I started doing the research, I noticed that the connector on the L-com patch antenna is SMA (implying 50 Ohm impedance?).

The specifications for this antenna indicates that it is good for video though.

The antenna connector on the Rx is Type F (implying 75 Ohm impedance?).

So it seems there is a mismatch here.

Probably my limited knowledge of this subject is to blame.

My understanding is that video gear uses 75 Ohm?

I also noticed on my 900 MHz Rx (Racewood) the antenna connector is SMA.

This confuses me more.

Anybody able to clarify this for me?

Thanks

Henk

[Mr.RC-Cam 129]

The F-connectors are not good choices for 1.2GHz, but you will find them on low cost A/V systems because of the savings to the mfg.

The satellite tuner modules found inside the 900-1.3GHz receivers typically have 75 ohm RF inputs, even when a SMA has been used. So, either way you end up with a 50ohm/75ohm situation. The minor mismatch is actually nothing serious to be concerned about. So, go ahead and use an RF adapter to convert the F-connector to SMA.

Honestly, I'd recommend you rescale the GP Patch for use on your frequency. It works great. After all, you're on a DiY site, where building things is king.