HP 212A - Troubleshooting Chart

Parallel combinations of lower wattage resistors may be used
successfully, however, lead and component length should be kept
as short as possible.
When R21 is replaced by a single,
cylindrical resistor, the re-
placement should be mounted so its axis is horizontal and paral-
lel to the side of the instrument.
Replacement
resistoYs for RZI !and R22 may be procured from
Hewlett-Packard Company. When possible, parts order should
be accompanied by serial number of instrument to be serjiced.
4-6 TROUBLE SHOOTING CHART
The following trouble shooting chart is a list of observed symp-
toms.
The solutions for each symptom are listed in order of
expected probability.
Each suggested remedy is followed by a
note giving cautions and checks that should be made following
replacement of a component. When no caution or check is listed,
the component may be replaced without other than normal pre -
cautions,
Dial calibrations will usually be inaccurate following
a tube change within a multivibrator circuit.
If a tube is removed
for checking and is not found faulty, it should be returned to the
same socket,