From time to time someone start searching for part number of the VFO encoder.
Here is a selection of part numbers for encoders without detent (no clicks) and with detents (like the original one).
To match the desire of the user, ICOM use a lever to "add" detents to some of their radios. When using in mobile, detents may be convenient while using it stationary, no detents might be the choice.
There are a lot of manufacturers that make cheap PC11 type encoder but the reliability is not very good; while they can be used in home-made projects, in the radio a more sturdy one is needed.
Also, they might fail and most hams try to find a faster way to repair the radio than to send it back to China and wait a few months.
Therefore, here are a few options for those "brave hams" that will take the things into their hands and will repair the radio by themselves.
As a personal observation, with more than 18 pulses per revolution it is a pain to use a no detents encoder...
No detens:
PEC11R-4020K-S0018 with knurled shaft, 20mm lenght, no detents, momentary switch and 18 pulses per revolution.
PEC11R-4025F-S0018 with flatted shaft. From ALPS, EC11E, 20mm long flatted shaft (only) momentary switch.
With detents:
PEC11R-4120K-S0018 - 20mm long shaft, knurled (4120F for flatted shaft), momentary switch.
PEC11R-4125K-S0018 - 25mm long shaft, knurled (4125F for flatted shaft), momentary switch.
No detents:
EC11E153440D with 15 pulses per revolution. Flatted shaft. 20mm long, momentary switch.
EC11E18344OC with 18 pulses per revolution. Flatted shaft. 20mm long, momentary switch.
With detents:
EC11E18244AU with 32 detents, 18 pulses per revolution. Flatted shaft. 20mm long, momentary switch.
EC11E15244B2 with 30 detents, 15 pulses per revolution. Flatted shaft. 20mm long, momentary switch.
Serrated (knurled). Please check the dimensions of the shaft for proper selection of the knob.
Without detent:
EC11G1574402 - 15 pulses per revolution, momentary switch.
With detent:
EC11G1564411 - 30 detents, 15 pulses per revolution, momentary switch.
For both producers I reccomend study their product selection datasheets which can be downloaded as pdf clicking on their names.
The pinout of the above encoders is compatible with the one in the radio.
I usually like to have longer shafts and cut them to my needs so, if you want a shorter one, just check the datasheets for the part number.
Both manufacturers are producing compatible encoders for VFO, VOL and FUNCTION.