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PCE
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DIFF Subgroup
H04L 27/28

with simultaneous transmission of different frequencies each representing one code element

Introduced: September 1968

Full Title

Full titles differ between systems:

IPC:

Modulated-carrier systems > Systems using multi-frequency codes > with simultaneous transmission of different frequencies each representing one code element

CPC:

Modulated-carrier systems > Systems using multi-frequency codes (H04L27/32 takes precedence) > with simultaneous transmission of different frequencies each representing one code element

No child classifications to compare. This is a leaf node in both IPC and CPC.