Demo #8: Unboxing and Product Review of Rown Fusny R03U Wireless Mono Headset | In The Lab

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In this video we unbox and demo the R03U Wireless Mono Headset sent to me for review by Rown Fusny. This headset supports wireless connectivity for both USB and Bluetooth. I really enjoyed using this product and their customer support was first class.

It’s a mono device which means it only has a speaker for one ear, which is really good for your situational awareness because you can hear what’s going on in your environment through your other ear. Both the headphone and the microphone worked properly in both USB and Bluetooth mode.

I wasn’t able to get the USB mode to work on my Windows 10 machine, but I don’t know if that was related to the USB hardware on that computer or if it had to do with Windows 10 support for the device. I was able to get USB mode working on a Windows 11 Pro computer and one of my Debian 12 (bookworm) computers. I tested the Bluetooth mode on both iPhone 6s and iPhone 8.

One thing that I needed explained to me was that after you pair your Bluetooth device you may need to double click the power button on the headset in order to toggle from USB mode over to Bluetooth mode in order to activate the device. That’s why I had to contact customer support, because I was confused by this.

The device gives you status updates via audio. So if you toggle to USB mode it says “USB mode” and if you toggle to Bluetooth mode it says “Bluetooth mode”. If you disconnect the USB dongle or unpair the Bluetooth connection it says “disconnected”.

There is a microphone mute button on the headset and there are volume control buttons too. I tested the volume control buttons via Bluetooth but forgot to test via USB… hmm. Gimme a tick. Yep, the volume controls work on USB too!

Overall I was very pleased with this device and I would happily recommend this product!

In preparing this video I made some notes about my headphones which are still available on my wiki.

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Yum Cha 16MP USB CameraThis is an image of the product.

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Analog Meters for Learning the Art of Electronics

I was flipping through my copy of Learning the Art of Electronics: A Hands-On Lab Course (I have the first edition, this second edition comes out in Australia on 3 April 2025, I have a copy on pre-order, I think it’s already available in the USA) and I noticed that some analog meters are used in the first lab course.

So in preparation for doing that I purchased some analog meters, being these:

I am planning to start working through these projects on my YouTube channel @InTheLabWithJayJay at a rate of one project every 28 days starting April 1st. April 1st, being April Fools’ Day, is of course the traditional date for launching IT projects and it is also the one year anniversary of my video (which happens to be my most popular YouTube video by a large margin): New Book Teardown #3: Learning The Art of Electronics: A Hands-On Lab Course (2016) | In The Lab.

Interlude #14: Making BNC to Jumper Pins Cables for My Oscilloscope | In The Lab With Jay Jay

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In this video we make two cables for use with my oscilloscope or other devices with BNC sockets. The cables have a BNC connector on one end and two male jumper pins on the other end. This is so that I can easily connect my oscilloscope (or signal generator) to a breadboard.

Equipment which I might use these new cables with includes my Rigol MSO5074 Mixed Signal Oscilloscope and my UNI-T UTG962E Signal Generator.

In the video we use the METCAL PS-900 Soldering Station for soldering.

We use the EEVblog BM2257 Digital Multimeter to continuity test the cables and to check for shorts.

We use the Horusdy Soldering Station with Hot Air Gun for shrinking out heat shrink.

We use the Hakko CHP 3C-SA Precision Tweezers for pulling the heat shrink over the wire.

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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!

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Voyager bug fix

This is too cool. A core dump then binary patch to work around memory hardware failure 15 BILLION MILES AWAY: How NASA Fixed a Software Bug 15 BILLION MILES AWAY | Voyager 1

Arduino Keyboard library not working on Debian KDE

Man, I just spent quite a bit of time diagnosing this particular issue.

The problem was that my Symbol Keyboard stopped working. This is a USB keyboard I made from an Arduino Leonardo. The touch screen was working okay, but the keypresses weren’t being delivered over USB.

Long story short, the 7-port USB 3.0 hub attached to my workstation needed rebooting! I disconnected the power supply and disconnected the upstream USB cable to remove both sources of power, then when I reconnected everything my stuff started working again, including my symbol keyboard.

Lesson learned: if you’re debugging a USB device failure try plugging the device directly into the host to avoid any potential issues caused by your hub(s).

It was lucky I had a spare 104-key USB keyboard in the cupboard because I needed one while diagnosing this issue (the Windows box I was using only has a tenkeyless 87-key keyboard plugged into it but the Windows alt-key codes require use of the number pad).

The latest incarnation of my symbol keyboard looks like this:

John's symbol keyboard

Unboxing #25: Unboxing the EEVblog BM2257 Multimeter | Learning Electronics 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.

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In this video we unbox the Brymen EEVblog BM2257 Digital Multimeter which arrived recently from my mate Dave Jones of EEVblog fame. Thanks Dave!

In the video I mention about the Multimeter Fuse Pack available at the EEVblog Store (but out of stock), but I don’t think that particular fuse pack has the fuses I need for the BM2257. I have asked about what fuses to get on the EEVblog Forum: Appropriate fuses for EEVblog BM2257 Multimeter.

The BM2257 came with Zinc–carbon batteries which I haven’t seen before. You learn something new every day!

There will be a demo video coming out soon to go with this unboxing video, just like I did for my Fluke 17B+ Digital Multimeter:

I am very happy to have my new BM2257. Thanks again Dave. <3

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Yum Cha BM800 Condenser MicrophoneThis is an image of the product.

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EEVblog BM2257 Multimeter

Dave Jones of EEVblog fame sent me an EEVblog BM2257 Multimeter. Score! Thanks Dave! The unboxing and demo videos will be coming out on @InTheLabWithJayJay next week.

I did check in the manual but I’m still a little confused about which are the best fuses to get, so I have asked over on the EEVblog Forum: Appropriate fuses for EEVblog BM2257 Multimeter.

John's new EEVblog BM2257 Multimeter

Concluding Maxitronix 20in1 | Maxitronix 20in1 | Learning Electronics In The Lab With Jay Jay

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In this video we conclude our Maxitronix 20in1.

The videos we made for this feature of the show:

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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 Double-ended Cotton SwabsThis is an image of the product.

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