Optical Encoder

[WA5VGO]

I have an N3ZI DDS VFO and would like to upgrade the encoder. I want an encoder with a 3/8” mounting bushing and a standard 1/4” shaft. I know absolutely nothing about this. His instructions suggest a Bourns type EM-14 as a good upgrade. These encoders are available with anywhere from 8-64 pulses per revolution. Which one do I need?

Thanks,
Darrell

[WBear2GCR]

I'm no expert, actually zero experience in practice. But, intuitively, if the program remains
the same, no modifications, the higher the number of pulses per turn the faster the rate
of change of frequency per rotation. More pulses per revolution.

Why not just ask N3ZI for the spec on the stock one?

Also there may some logic variants, such as pulls high or low...

                    _-_-

[MikeKE0ZUinkcmo]

HERE'S ONE, and THIS IS ANOTHER TYPE

Mike

[w8khk]

Mike offers some nice options, here is what I used:

Signswise 600p/r Incremental Rotary Encoder Dc5-24v Wide Voltage Power Supply 6mm Shaft  $16.99

https://www.amazon.com/Signswise-Incremental-Encoder-Dc5-24v-Voltage/dp/B00UTIFCVA/ref=sr_1_3?gclid=EAIaIQobChMIysedk4qn5AIVw56zCh2ygQfMEAMYAyAAEgIxQ_D_BwE&hvadid=175901296281&hvdev=c&hvlocphy=9010790&hvnetw=g&hvpos=1o3&hvqmt=e&hvrand=8306219883670471058&hvtargid=kwd-29187206&hydadcr=25938_9540024&keywords=optical+rotary+encoder&qid=1567047332&s=gateway&sr=8-3

I use it to directly control the frequency of my DDS with an Arduino Nano processor.  The tuning rate may be adjusted programmatically  by dividing the count in software before processing.

This takes a nice heavy knob with a 1/4" shaft hole, no detents, ultra smooth tuning for small or large frequency excursions.