
STE sas Milano - ITALY
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General Description
The BK77A5 and the BK77B5 are “PLL” synthesized UHF transceivers for use in Wireless
“Voice” ( Analogue Signal ) or “Data” transmission applications.
The transceivers operate on the 433.05-434.79 MHz ISM Band and are designed to comply to
the European Standards EN 300-220-3 ( class I ) and EN 301-489-3.
The transceivers employ NBFM ( Narrow Band Frequency Modulation ) with a 25 KHz
channel separation. The programming frequency step is 12.5 KHz.
A) BK77A5
The BK77A5 is designed in accordance with CEPT-ERC/REC 70-03 recommendation
( Annex 1 – Non specific short range devices ) for applications employing a 10 mW
max radiated power ( ERP ).
B) BK77B5
The BK77B5 has 500 mW output RF power ( 100mW in “ Low Power” ) and it is
programmable from 432 MHz to 436.1 MHz ( to cover also the Italian 436.000-
436.100 MHz Telemetry and Data transmission band ).
Fig. 1
CEPT ERC/REC 70-03 ISM 434 MHz Band.
Annex 1 – NON SPECIFIC SHORT RANGE DEVICES
ERP = 10 mW
Duty-cycle < 10%
433.05
434.75
MHz
Pout
10
mW
434.79