No registered 14C counts

There are no registered ¹⁴C counts.

1. Start a single run on a known standard (OxII).

2. Check that the ¹²C currents are still present (20 - 30 μA ¹²C⁺ on a solid sample).

3. Look up tuning settings from a previous time when the system was working:

   1. Compare with present settings to see if a setting is significantly different than usual.

   2. Apply the old settings.

4. If the ¹⁴C counts are still missing, check the detector settings:

   1. Check that the bias voltage is set.

   2. Check that the detector pressure is stable.

   3. Adjust the discriminator setting if necessary.

5. Make sure the slits are not blocking the beam.