Update - Rotary Encoder Contact Bounce on the UBITX Transceiver

Rotary encoder quadrature output

In my previous post I mentioned that the hardware filtering of the rotary encoder had improved the reliability, but occasionally I would still get inconsistent results, especially when turning the knob quickly.

Rotary Encoder Contact Bounce on ubitx

Unfortunately, after a while the reliability got worse again. I suspected either dirty contacts or a faulty rotary encoder.
I squirted a load of switch cleaner/lubricant (Servisol Super 10) into the gaps in the housing and rotated the encoder a few times. After allowing time for it to drain/dry I switched on the radio and tried tuning it with the rotary encoder. It worked flawlessly.

Conclusions

No amount of filtering will fix a faulty rotary encoder, or one with dirty contacts.
However, I still recommend using adequate wetting current and applying some filtering, either in hardware or software (refer to original article). Any mechanical rotary encoder with exhibit some degree of contact bounce/chatter and operating the contacts at very low currents will make them less reliable.

If I get any more problems with the rotary encoder I think I shall be replacing it.

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