A new skill – installed a waste water pump on the boat

Our boat came with a very nice kitchen, and a Belfast sink. All very nice, but it was draining at a extremely slow pace. After checking for blocks etc. we discovered that the fall between the outlet of the sink, and the outlet from the boat, there was next to no vertical drop.

So the solution would be to either move the Belfast sink up, or install a punp.

I went for the last option, and as I wanted this running off the boats 12V system (we have 230V mains as well – but for lots of reasons I did not consider this a good solution). And that led us to the Whale Gulper pump.


Reading up on marine pumps it comes very highly recommended – so we ordered one, and today was the day to install it.

All very simple, and when I connected it to 12V it immediately drained the sink! Success.

Now I just need to find a suitable switch for it – but that’s for the next visit to the boat.

The small things in life

Early yesterday morning one of our neighbours rang the doorbell with the message “there are a number of BT guys outside with cables”.

Of course I walked out to talk to them, and there they were with a big roll of fibre just outside our door! As they were from OpenReach there was not a lot they could say, except to confirm that we would get fibre to our doorstep, and that in 5-6 weeks time we would get activated.

For us – incredibly good news, as we have all kinds of niggly problems with both our broadband and telephones!

Good things may be coming for Christmas!

Redis is innovative again

ReJSON: Redis as a JSON Store
We’ve created ReJSON, a Redis module that provides native JSON capabilities. ReJSON should make any Redis user giddy with JSON joy.

I have used Redis for many years – both as a database cache and as a super fast in-memory database. But it has not evolved a lot for  a long time.

But this seems to have changed – RedisLabs (the commercial arm of Redis) has released a number of opensource/commercial modules for Redis.

The first one I have looked at is RedisJSON – as I saw the potential to upload a whole Azure Cosmos database for one of my projects into Redis, while improving speed and drastically lowering costs. (Cosmos is well known for being expensive to run.

So I’m currently writing a POC to test out my theories – onwards and upwards.

Remote control of Raspberry pi on boat

We now have a (rather good) LAN on our boat – but the last challenge is to access the computers on the boat.


4G networks do not generally hand out a IP address per endpoint, not even a dynamic IP address. So other means need to be used, and I stumbled across https://remote.it/, which has a free service for single endpoint use.

And they supply their own management apps for MacOS and IOS etc., or you can use other protocols (including VNC) to access the Raspberry pi.


I have just installed it, and will move the Raspberry Pi to the boat this weekend. As a matter of fact I will move 2 Raspberry Pis there, one to be a Plex/Kodi server, and one to manage our power devices – as we supply power from batteries/solar panels/generators/engine/shore, and it all needs monitoring to ensure it works correctly.

Raspberry pi, 1wire protocol and stability

After we installed a new boiler and a 10 port manifold to control our (waterborne) I needed to find out which heating loop from the manifold went where without spending weeks on my knees turning loops on and off manually, and then wandering around barefoot to find out which part of the floor was affected.

So I decided to put temperature sensors on every loop and a few other strategic points in the heating system.

So far I have 16 temperature sensors (DS18B20 sensors) controlled by 2 Raspberry pi Zero’s.


Why 2 Raspberry pi Zeros? – Well I ran into problems when I went above 10 sensors on the first raspberry Pi Zero, and decided to see if I could solve this part of the puzzle – as (for all I knew) there was a software or bandwidth limit stopping me at 10 sensors.

The DS18B20 uses a rather ingenious protocol called 1Wire, which enables a “multi drop” configuration of sensors originating from one set of wires. It can be run with 2 wires (parasitic power) or 3 wires (plus, round and data wires). I went for the last one – as using parasitic power sensed one step too far for me. So I used a breadboard attached to the Raspberry pi to make it easier to experiment.


I have had quite a few problems with this – even though the circuit is simple :


I’m using a bit more of a “star” configuration, as each sensor has approx 1m of cable connected to it.

I had a number of problems where the Raspberry Pi’s stopped working at “random” intervals – and lot of experiments with resistor values, swapping of power supplies and so on did not sort the problem out.

The solution to the problem (for me in this particular case) turned out to be the wireless connection to the LAN, as soon as I put a access point close to the Raspberry Pi;s – all stability issues of this type went away!

(More about the setup later)