Too many buttons

 I have a standard ham licence (VK7HPC) and am currently poking at a Retevis RT95 (same as the Anytone AT-778UV). As I'd like to use it for digital modes, Steve (KM9G) over at Temporarily Offline Ham Radio has a playlist where he's investigating the pinout to make a microcontroller APRS interface, however he's not yet mentioned how to memory jump or enter a direct VFO frequency. Sure CAT control would be nice, but this radio's under 200 AUD delivered, so that's unlikely to happen. 

So, the manual hints at "keypad serial data" on pin8 so with a bodge together of 2 cat5 outlets, some wire and a logic analyser, lets see what we can find...

Force of habit means I used the T568A colours, so the from the pinout shown here you'll need to swap the orange/green pairs round. 

Anyway: Up, Down, PTT all get pulled to ground when pressed as expected and there IS some serial data on pin8, now I need to sample and collect more...

Update

In a stroke of good fortune, it appears to be plain ascii at 9600 baud. Pressing each key in turn spat out AL~K1, AL~K2, ... AL~Kx where x is 0-9,*,#,A-D and / (the latter being the toggle for A/B input)

Next up will be introducing it to little bobby microphone and seeing if I can send commands to the radio directly from a microprocessor

Particulate measurements near bushfires

Back in the 2019 Tasmanian bushfires we were lucky enough to be the other side of the Huon River from the fireground,  however we had a LOT of smoke (compare the photo below to the street view image)

We were also lucky enough to take part in a Huon Valley trial to compare HEPA filter systems which used a pair of CSIRO Smoke Observation Gadgets (further details on these units in Sensors 2021, 21(21), 7206; https://doi.org/10.3390/s21217206) to log the air quality (pm2.5 and pm10 measurements) inside and out. 

It's now 2025, and while we've been very lucky compared to the US and mainland Australia, we now have a bushfire nearby (~6km from our house) that contains the following advice:

Residents should be aware that smoke and ash may be visible in the Channel area over the coming weeks, and anyone who is at higher risk from smoke should enact their personal health plans.

So, it's time to DIY some new smoke sensors! (I would just rely on the excellent BLANkET network already in place in Tasmania, but there aren't any downwind of the current fire)

Hardware

I already have a pair of PMS7003 sensors unused in a 'future projects' box, so we'll use them. They are supported by esphome, so using an esp32/esp8266 with them seems a simple choice

Mine (located in Kettering) will use a wired esp32 (because POE makes that simple), and I'll see if I can get one mounted at the Channel Men's Shed in Margate which will need to use wifi

I don't have a nice shiny 3d printed enclosure, so it'l use something like an old yoghurt tub to weatherproof them.

Build

.. To Be Continued at the weekend :-)