  We use a new phase-calibration strategy to calibrate the phase of 86 GHz VLBI
observations of the FR I radio galaxy NGC 4261. Instead of switching between a
calibrator source and the target source, the target was observed while rapidly
switching between the target frequency and a lower reference frequency.
Self-calibration at the reference frequency yielded phase corrections which
were multiplied with the frequency ratio and applied to the target frequency
visibilities. The resulting detection of NGC 4261 is, to our knowledge, the
first of NGC 4261 with 86 GHz VLBI, and it is also the weakest source so far
detected with VLBI at that frequency.
