This AM radio still costs thousands of dollars—why?

Video Description

My Dad put his Potomac FIM-21 Field Intensity Meter on the bench. In 1986, this radio cost $1,950—which is nearly $6,000 today! (And this isn't even the most expensive AM radio today—there's a newer version for $15,000!) It measures the field intensity of AM radio signals in volts, and a calibrated unit like this one can be used for official readings sent to the FCC for broadcast stations in the US. A few other things we mentioned in this video (some links are affiliate links): - Potomac FIM-21 Field Intensity Meter: https://pi-usa.com/legacy-products/ - RTL-SDR v4 dongle: https://amzn.to/3KvDbku - SaferCCTV AN-200 Indoor AM Loop Antenna: https://amzn.to/3KvDdZE - Gqrx SDR software: https://www.gqrx.dk - We made a hot dog talk... with RF: https://www.youtube.com/watch?v=GgDxXDV4_hc - Workbench build video: https://www.youtube.com/watch?v=JV1Iv9bXkdI Support me on Patreon: https://www.patreon.com/geerlingguy Sponsor me on GitHub: https://github.com/sponsors/geerlingguy Merch: https://www.redshirtjeff.com 2nd Channel: https://www.youtube.com/@GeerlingEngineering 3rd Channel: https://www.youtube.com/@Level2Jeff Contents: 00:00 - Field Intensity Meter 21 01:13 - Over 900! 02:22 - How to take a measurement 03:14 - Loop antennas, nulls, and SDR 05:56 - External antenna testing 08:16 - What about FM? 09:16 - Why it costs thousands of dollars 10:46 - Field Calibration 13:33 - Is it still useful? 14:46 - The importance of calibration 15:50 - Justifying the cost... with a hot dog?