Low-Water Indicator | Project 17/20 | Maxitronix 20in1 | In The Lab With Jay Jay

This post is part of my video blog and you can find more information about this video over here.

You can support this channel on Patreon: patreon.com/JohnElliotV

In this video we do the 17th project from the Maxitronix Sensor Robot 20 (20in1) Electronics Project Lab Kit: Low-Water Indicator.

We use the Rigol MSO5074 Mixed Signal Oscilloscope to see the output of the astable multivibrator. In the video I make a mistake and attach the probe to the wrong pins.

We use the METCAL PS-900 Soldering Station to solder the wires I use for the banana plugs I attach to the touch sensor an voice sensor (microphone).

We use the UNI-T UTi260B Thermal Imager to look at the heat profile of the circuit. We see that the low resistances (470Ω and 1KΩ) get the warmest, but the higher resistances (e.g. 10KΩ) are also slightly visible.

We use the Fluke 17B+ Digital Multimeter to check the resistance of the touch sensor.

We use the Peak Electronic Design Atlas LCR45 LCR Meter to measure the resistance of the resistor we use in the LED attachment circuit. This extra circuit allows us to switch out the buzzer for an LED, which makes a lot less racket. The resistor it uses turned out to be 470Ω.

We use the Riden RD6006 Bench Power Supply to provide 9V for our test circuit. Usually I take a current reading to see how much power the circuit draws in its various states, but I forgot!

We use the Horusdy Soldering Station with Hot Air Gun for its hot air gun in order to shrink the heat shrink which we added to the banana plug cables we attached to our sensors.

Thanks very much for watching! And please remember to hit like and subscribe! :)





Following is a product I use picked at random from my collection which may appear in my videos. Clicking through on this to find and click on the green affiliate links before purchasing from eBay or AliExpress is a great way to support the channel at no cost to you. Thanks!

Yum Cha 9-Inch Needle Nose PliersThis is an image of the product.notes

Let’s go shopping!

Mail Call #16: METCAL PS-900; Peak Atlas DCA75 Pro, LCR45, ESR70; ESP32; Pi Zero, Pico; and More!

This post is part of my video blog and you can find more information about this video over here.

You can support this channel on Patreon: patreon.com/JohnElliotV

In this video I receive the following equipment in the mail:

As I mentioned the open-source architecture books are available free online: The Architecture of Open Source Applications.

Thanks very much for watching! And please remember to hit like and subscribe! :)


Following is a product I use picked at random from my collection which may appear in my videos. Clicking through on this to find and click on the green affiliate links before purchasing from eBay or AliExpress is a great way to support the channel at no cost to you. Thanks!

Aussishop CalipersThis is an image of the product.notes

Let’s go shopping!

METCAL PS-900 Soldering Station

Update: my notes about my METCAL PS-900 soldering station are on my personal wiki, over here: METCAL PS-900 Soldering Station.

The other day I was doing some soldering with my Horusdy Soldering Station but I got the feeling its soldering iron was under performing. I just wasn’t getting good solder joints even though I was using good solder and plenty of flux.

So today I did some research and found myself a new soldering station: METCAL PS-900 Soldering Station. I found one for sale on element14 for AU$458.59 which as far as I can tell was a really good price. They were going for more like AU$700+ on Amazon, eBay, and even AliExpress.

I did also research and consider some other options from JBC, Metcal, Weller, and Hakko.

I also picked up a couple of spare tips:

The tip it came with was the METCAL SFV-CH10, 30° Chisel, 1.5 mm Soldering Iron Tip.

I am expecting that the 1 mm chisel tip is going to be my weapon of choice, so I got two of those. (Update: this was a mistake, the 1.5mm or 2mm option would have been a better choice.)

Conspicuously absent on this soldering station is a temperature setting. That’s because these METCAL irons come with SmartHeat technology, as ChatGPT explains. For the SFV-CH10 the Curie point is designed to maintain a nominal tip temperature of around 380 °C (715 °F) under typical load conditions.