As described by John Ehlers :
This pass-band oscillator seeks to pass-band out both high and low frequencies from
market data to eliminate wiggles from the resultant signal thus
significantly reducing lag. This pass-band indicator achieves this by using 2
differenced EMA's of varying periods. (40 and 60). Trigger points for
the pass-band oscillator are added with a RMS cyclic envelope over the Signal
line. Output of the pass-band waveform is calculated by summing its square over
the last 50 bars and taking the square root of the averaged sum to
create trigger levels.
Buy when pass-band crosses above its -RMS line. Short when pass-band crosses below the RMS line.
Deviation from the original is that different calculating periods are allowed (defaults are as he described, but any calculating periods are allowed)
This indicator also has somewhat unusually big choice of prices - 22 types - you shall find their descriptive names in the drop down choice box for prices (they are self descriptive so there should not be a problem in recognizing what do they stand for)
Indicator is already having all the usual set of alerts and is multi time frame. Addition of filled areas when the RMS envelope is exited is added in order to help pinpoint (along with alerts) the moment when the break happens. Some parameters experimenting is advised though - John Ehlers usually tests his idea on commodities - where the volatility is significantly lower than in forex - and some adjustments to forex conditions are probably a sensible choice