It was a double wall screen room
With 5W HTs a foot apart, one inside, one outside, caming the door shut
took them from overload to being undetectable.
At the time (before I quit and went to college) I did the RFI
measurements and instrument calibration for the plant. The signal
strength measurements were done with a Singer Metrics receiver. The
isolation was beyond its ability to measure.
73
Roger (K8RI)
On 12/5/2016 8:08 PM, jimlux wrote:
On 12/5/16 1:06 PM, Roger (K8RI) on TT wrote:
When I was a tech my desk was in a double wall commercial screen room.
The screen was Copper. The door shut into a frame lined with heavy
finger stock. The door latched using a cam.
Commercial screen rooms do use copper screen.
Indeed - http://www.ets-lindgren.com/iDEI-Screen
I wonder, though, what the attenuation of that is vs the solid panels.
Screen - double layer electrically isolated
Magnetic (14 kHz): 68 dB
Electric (14kHz): 120 dB
Planewave 450 MHz: 110 - 120 dB
Planewave 1 GHz: 90 - 110 dB
Microwave 10 GHz: 50 - 80 dB
vs a solid (Lindgren type 81) single layer
Magnetic Field
20 dB @ 1 KHz
56 dB @ 10 KHz
100 dB @ 200 KHz
Electric Field 100 dB from 200 KHz
thru 50 MHz
Plane Wave 100 dB @ 50 MHz to 1 GHz
Microwave 100 dB @ 10 GHz
So it looks like a single layer screen is not as good as a single
layer solid..
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