Part 15 testing

[itsmoked]

For a simple small product that can be dropped into a test space and isn't expected to have any issues at all does anyone have a cheap test site for Part 15 registration.

Or does someone have a setup that lets them prove their product meets the requirements so a test house can be asked to quote on a slam dunk?

Keith Cress
kcress -

http://www.flaminsystems.com

 

[MacGyverS2000]

At my former place we used a space we created... a relatively small room (closet?), conductive pyramid foam on the walls, rotating table, etc. Nothing special, and the foam was probably the most expensive piece in the room, by far.

Dan - Owner

http://www.Hi-TecDesigns.com

 

[itsmoked]

And a $70k oscilloscope with a spectrum analyzer option?

Hadn't thought about doing it myself.

Did you use a hand-held antenna hooked to a scope and do a walk-around?

Keith Cress
kcress -

http://www.flaminsystems.com

 

[Skogsgurra]

A turn-table and a fixed antenna is a lot better. Use a small geared synchronous motor that doesn't contribute to EMI level.

The biggest difficulty is to stop external EMI from getting in. Use line filters for your mains connection. And double walls are always nice.

Do a reference run to see what the residual levels are and then subtract the reference level from the actual device's measured level.

This will take you a long way when getting it right. But you may need a final "official" measurement.



Gunnar Englund

http://www.gke.org

--------------------------------------
Half full - Half empty? I don't mind. It's what in it that counts.

 

[MacGyverS2000]

As Gunner said, it was a rotating table and a fixed antenna.

Scope is outside the room, so I didn't include that in the cost ;-)

No need to purchase an expensive scope... plenty of older stuff will be acceptable. I have a spectrum analyzer from the 70's (?) that cost me $20 (got three for $60, actually, and sold the other two on eBay for around $2k total), good up to a couple GHz.

Dan - Owner

http://www.Hi-TecDesigns.com

 

[VEBill]

I assume that final testing would have to be performed at an FCC accredited facility. This probably carries a minimum baseline cost in the low thousands.

Also, if you get into anything marginal, then a homebrew test set-up probably wouldn't be precise enough to determine which side of the limit the UUT sits.

The accredited lab will of course provide the actual graphs, so one could (afterwards) go home and try to replicate those exactly... ...assuming one has many months of free time and unlimited patience.

 

[DRWeig]

Least expensive I have found is ETL, but TUV, Metlab are in the ballpark. The last "easy" one I did cost maybe $2500 if my memory is working right tonite (caution: that's not always the case).

Is your device an intentional emmiter or an unintentional emitter? What's the highest frequency inside? Lots more things can be exempted from part 15 than you'd expect if you read carefully...

Good on ya,

Goober Dave

 

[itsmoked]

Hi DW.

Unintentional, battery power-able (for testing) 8MHz internal RC oscillator.

If I use a Credence ScanEM-EC probe turned to maximum sensitivity it doesn't sense anything anywhere on the board. If I use a ScanEM-HC probe in one very specific place it senses enough to change the brightness of the probe's first (green) of 5 LEDs about 50% once a second.

As for TUV, that is the biggest bunch of jerkwads I have evah had the displeasure of trying to work with. I cannot understand how they stay in business. An awesome demonstration of ineptitude, created by mandatory rules, I have ever seen.

ETL seems to have been sequestered by Inertek. They appear to have their act entirely together but the prices are way beyond the subsumed ETLs.

Keith Cress
kcress -

http://www.flaminsystems.com

 

[Skogsgurra]

You know, TÜV (Technischer ÜberprüfungsVerein) has German roots. EMC in EU is mostly tougher than FCC 15. I guess they may have a problem getting used to FCC 15. Also, in Germany "Ordnung muss sein!" Don't expect them to be less difficult than the IRS. But they are also after your money.

If you were in EU, you could present a TCF and self-declare that your device is OK. Does that possibility exist in the US? Of course, you need to be fairly sure about what you say.

Gunnar Englund

http://www.gke.org

--------------------------------------
Half full - Half empty? I don't mind. It's what in it that counts.

 

[DRWeig]

8 Mhz is over the exemption limits, so actual testing is required instead of self-declare that Gunnar mentioned.

Since you haven't mentioned the exact nature and use of the device, though, it might be worth taking 10 minutes to review the list of exceptions. There are quite a few. Section 15.103.

http://transition.fcc.gov/oet/info/rules/

Good on ya,

Goober Dave

 

[itsmoked]

Hi Skogs. Yep, I know TUV is German related and hence it's even more puzzling that the place is so screwed up.

Dave; Thanks a bunch for that link. Good stuff there that's clearly written. There are a lot of exemptions I wouldn't have expected.

Keith Cress
kcress -

http://www.flaminsystems.com