Saturday, 7 December 2019

Nano Controlled Step Attenuator


Long time since my last posting but there has been always some sort of activity going on in the shack. Most of the time has been devoted to developing an all band transceiver. I’ll post something on this at a later date. It has been a challenge and hard to know where to start for the post.

I’ve also started a long time waiting project, Auto Step Attenuator.  For this project I’ll be using the pe4302 chip board from eBay. I had one for quite a while now but I've ordered 2 more which will be used in this project.  It will likely be in the new year to complete as I don't think I'll get the parts before Christmas. But one never knows.

DuWayne KV4QB, has done a Step Attenuator project and was kind enough to give me a board he designed for it at FDIM this year. So, I will not reinvent the wheel here and follow his design.  Thank you DuWayne. Here’s a link to his blog where you can read not only about his attenuator project but other great things he has done. http://kv4qb.blogspot.com/

As is with DuWayne’s project, I’ll use 2 pe4302 boards connected in series with the control lines in parallel. This will mean that the attenuator steps will be in 1dB increments which is fine for anything I’ll require. Max power input is +24dbm which is again fine for my purposes.