RF Shield for the A1200 Needed

Peter Corlett abuse at cabal.org.uk
Wed Jan 21 07:04:41 CST 2015

On Tue, Jan 20, 2015 at 12:53:25PM -0600, Chris Elmquist wrote:
> On Tuesday (01/20/2015 at 05:21PM +0000), Peter Corlett wrote:
>> The original purpose of the shield is presumably to satisfy 1980s-era FCC
>> emissions rules preventing stomping over HF, but that boat has *long* sailed
>> and HF is just a wasteground now.
> Ummm.  No.  Speaking as both an Extra Class amateur operator active on HF and
> an electrical engineer developing embedded system products that must comply
> with the law, the boat has not sailed and HF is not a wasteground by any
> stretch of the imagination.

The bellyaching from British hams about dodgy ADSL and powerline kit stomping
over HF must be a complete figment of my imagination then.

>> (Here in EU-land, we never needed to give a damn about FCC regulations even
>> back then.)
> Effectiveness of the shield being discussed aside, FCC part 15 absolutely
> still requires testing across the HF spectrum and up to 1 GHz.  If the device
> will be used in a residential environment then you must submit your test
> results from a certified test house to the FCC for filing.

> In the EU, unintentional radiator emissions are governed by IEC, TC77, CISPR
> and ISO and devices need CE certification and labeling. The rules are far
> more strict than those in the US.

I have but a lay understanding of the various rules regarding CE marking, but
it's still ultimately a self-certification scheme that doesn't seem to see much
enforcement in the UK.  Occasionally there's a news story about Trading
Standards doing a bust on counterfeit and mismarked goods, but it's like drug
busts in that it's newsworthy because its a rare occurence, and supply mostly
continues unabated.

In particular, OFCOM is the government department whose job it is to police the
radio spectrum, and enforcement is slow and spotty.  Given I could probably
stand outside of their office with a FM radio and pick up a half-dozen pirate
radio stations, this is very much a department that needs a boot up its arse.
Long gone are the days of the Radiocommunications Agency whose officers had
much the same search and seizure powers as Customs and tax officials, but
without the cheerful and forgiving nature.

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