UHF MASKING


 Masking is the phenomenon whereby certain sounds are not heard because of the simultaneous (or near-simultaneous) presence of other sounds of a similar frequency but at a higher level.

Back in the 1960's experiments were carried out to try and create UHF Masking to disguise [or hide] UHF Voice/Data transmissions.

The trials involved Fleet fitted UHF gear {692's and 696's - see Transmitter page}, an ordinary noise source, and a special aerial which was not named or branded.

The following pictures come from that time.

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692 TX

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696 TX

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696 TX's

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MASK NOISE SOURCE

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MASK AERIAL REFLECTOR

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MASK AERIAL