Tabor Electronics 5251, User Manual

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TE5251
User Manual
1-10
SCLK IN
This SMB connector accepts sample clock signals from an external
source. Signal range is from dc to 250 MHz and amplitude level is
PECL (positive ECL level). The purpose of this input is to replace
the internal clock generator either for low noise applications or for
synchronization purpose. The sample clock input is active only after
selecting the external sample clock source mode.
REF IN
This SMB connector accepts 10 MHz. Signal level can be either
TTL or 0 dBm, depending on the selection made on the jumper
settings that is made on the board. The instrument is supplied with
TTL input setting. Changing to 0 dBm can be done only when the
card is removed from the chassis and only by qualified service
engineer.
The external reference input is available for those applications
requiring better accuracy and stability reference than the one
provided inside the 5251. The reference input is active only after
selecting the external reference source mode.