Poor Man’s Conductive Pre-Compliance Testing

I want to do some pre-compliance testing on Scammer Jammer. I have an inexpensive spectrum analyzer to do radiated testing. Conductive testing requires more expensive equipment.

First, you need an LISN device and, in my case, it needs to be connected to 110V and I’ve learned trying to do that myself is expensive and dangerous. Plus, the testing is, according to this, is in the frequencies 150kHz to 30MHz. My spectrum analyzer STARTS at 30MHz. There is no way for me to test frequencies that low with equipment I can afford.

While researching pre-compliance testing, I stumbled across this article:

http://www.compliance-club.com/archive/keitharmstrong/emc_testing2.html

According to that article, you can wrap an extension cord around an AM radio, connect it to the power mains, connect the other end to the device under test, and then you can hear any EMI on the radio.

I tried using a radio in this manner, and sure enough found Scammer Jammer’s LCD back-light circuitry was creating a lot of noise.

The following video shows how I setup the radio and tested Scammer Jammer:

I am using a Radio Shack DX390 General Coverage Receiver or (Sanjean ATS 808). A normal radio’s AM band covers 540kHz to 1210kHz. My radio also supports the long wave band which cover 150kHz to 540kHz.

https://www.hkvstar.com/images/articles/588_ISM_Bands.jpg

 

Advertisements
This entry was posted in c-electronics and tagged . Bookmark the permalink.

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Google+ photo

You are commenting using your Google+ account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s

This site uses Akismet to reduce spam. Learn how your comment data is processed.