HP 8647A - Page 124

604
Description
Cause
What
To Do
605
Description
Cause
What To Do
608
Description
Cause
What To
Do
611
Description
Cause
What
To Do
6 12
Description
Cause
What
To Do
+38Vpouer supply failure
The +38 V diagnostic test point decreased by more
than approximately
2.2 V.
The +38 V supply on the A2 power supply has failed.
Check the
+38 V supply.
ALC out-of -lock div het main band
The ALC loop is out of lock in the indicated bands.
Either the
A6 output has failed, or the signal from
the
A5 synthesizer has failed or the A4 reference has
failed.
If only the het band has failed it is possible
that the
A4 reference has failed.
Check the input to the
A6 output from the A5
synthesizer and the A4 reference.
Synth out-of-lock divhetmainband
The synthesis loop is out of lock in the indicated
bands.
Either the
A5 synthesizer has failed, or the signal
from the
A4 reference has failed.
Check the input to the
A5 synthesizer from the A4
reference.
200
kHz reference missing at synth
The A5 module indicates that the 200 kHz reference
signal from the
A4 module is not being detected.
Either the
A4 module has failed to output the 200
kHz reference signal, or the A5 module is failing to
detect the signal.
Check the
200 kHz reference output of the A4
module at the input to the A5 module.
Reference out-of -lock at 10 MHz
The A4 module indicates that the 10 MHz reference
VCO is out-of-lock.
Either the
A4 module has failed or a bad external
reference is connected.
Disconnect any external reference and power-up the
instrument again or replace the
A4 module if the
error is still present with no external reference.
Service Error Messages 50-5