Re: Fried Ch0 S11 port #hardware


Reinier Gerritsen
 

It's not the RFID reader that caused the problem, it's the antenna I'm designing. And these antennas are just a stack of sheet metal and spacers, all of the right dimensions of course. I need the VNA to tune the antenna to the exact frequency and impedance I need. Adhesive copper foil, a sharp knife and lots of experience is all you need.
I'm not sure what would happen if I put a 1W RFID transmitter directly at the input, I would probably fry some tiny resistors ;). By the way, RFID is of course well regulated for safety. The output power from the antenna is limited to 2W ERP in Europe. Safe distance is around 25 cm.

Reinier

Op 30-11-2020 om 11:28 schreef Stephen Laurence:

Thankyou. I am learning all the time (got to keep a 70yr old brain alive somehow).

I am getting some switches just in case. I have tools to (theoretically) replace them (controllable hot air gun, tweezer soldering iron, cheap Chinese microscope etc) and some dead Ipads to practice on.

However I will be careful. I am surprised rfid equipment could cause damage as it has to be safe for the public and equipment they might be carrying ( eg phones). Nevertheless, I might buy a stock of these diodes as well.

A stack of built v2 boards might be a good investment too, as most of the v2 variants (v2N, my favoutite) use it with additional bespoke boards for the niceties (display, switches etc).

Steve L

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