I see that having the "Dollar Tree" plate engraved would have broken the FDIM awards budget. Thank goodness someone remembered to bring a "Sharpie" marker or Hans effort would have gone unrecognized. 😀 I am reminded of an old joke about a man who was tarred, feathered and threw out of town on a rail. When asked how he felt about it he replied "If it wasn't for the honor of the proceedings, I've just as soon have walked!"

That is completely awesome, Hans! I do especially love your heatsink innovation! In hindsight that I would not have anticipated until I saw the drinks in the video, you could double the duty of your device as a "tea maker" by immersing the tubes in cold (distilled) water and running the supply voltage up, up, up!

Wow! Smart design and excellent result. Congratulations, Hans!

I love to see what happens when people think outside of the box ... absolutely brilliant ! - de VE3WMB

Great work 🙂👍 Looked like you had a lot of fun with a great crowd.

Ingenious, especially the xtal coupling. Well done.

@joeteejoetee

2 жыл бұрын

Yes indeed!

What great fun, Hans.

👍❤

Well done Hans!

Very interesting (and remarkably clean)! Well done! I've always thought those old metal can 2N2222 "switching" transistors are quite amazing devices, and will lend themselves to almost any application. Out of interest which of the many manufacturers who produced it, made the 2222's you used?

nice to see David NM0S there helping

I love this sort of contest, and Hans has knocked it out of the ballpark.

What great fun that would have been. I would like to do something similar one day. Could that be referred to as "overclocking"? How clever. Enjoyed, Thanks for sharing.

I can see in the video that the official power measuring device was a QRPometer, designed by Dave Cripe NM0S.

@Randrew

2 жыл бұрын

I was wondering why the certificate said David Cripe was the president of N-type Metal Oxide Semiconductor. Ha! That was a 0, not an Oh.

@joeteejoetee

2 жыл бұрын

Where can I buy one of these?

Wonderful effort Hans, so much fun when amplifier theory and practice come together in something like this. Loved seeing the device under a perspex safety cover, in case of 2N2222A thermo non nuclear destruction!

👍Well done Hans and thanks for sharing. I remember a while back wondering if I could build a XTAL controlled astable RF multivibrator TX. I think an audio astable multivibrator was one of my first projects as a kid 😊. I wondered about using BC107s or IRF510s. Using transistors that can handle the current without the crazy big heatsinks might make for a useful simple QRP TX circuit that would give a few Watts out? I wonder if you tested your 2N2222A TX on air? Perhaps how it sounded in terms of chirp?

Thank you very much for this very technically detailed video. Bravo. 73's ! KJ4QJF

I'd love to see something like this with a dual section thermionic valve!

Also see my colleagues from Collins ARC in the Background

When I saw the two coppers tubes, I immediately assumed that you had implemented 'heat pipe' technology. It seems that you haven't. Heat pipes would be a simple modification: Ensure that the 2N2222A transistors are tightly sealed into the tubes (already done that step I'll bet), then add a phase change fluid/gas, and turn the assembly vertical (2N2222A at the bottom), and add additional heat sink area at the top. Pressure in the tubes might need adjustment, depending on the fluid/gas chosen. The liquid phase fluid will boil and carry away heat to the top, where it'll condense and flow down to repeat the cycle. Heat pipes can carry away many times the heat of a normal copper pipe. Temperature should be stable and thus power could be nudged up further. For additional ideas, look into the crazy computer 'Overclockers'.

I love nerds!!!

Concratulations Hans! I thought that the 5W on the QCX and Co, are a good choice, to have a simple and effective PA. But I have to 'replace' my mind! This is far, the more interesting way, ... ! "We salute you!" 73/72 de Markus ; db9pz

@everettcatlin4328

2 жыл бұрын

Congratulations Hans DE WA2BHS

Thanks Hans - an inspiration. Apart from the crystal the circuit appears quite similar to the Kalitron oscillator as featured in various RSGB books from the '60s & 70s. My brief experiences is that they start up reliably when free running. Over a wide frequency range too. I wonder what power you could get out from one using BD139s, or maybe a Darlington pair arrangement.

@vk3ye

2 жыл бұрын

Hans - another thought. There's balanced mixer circuits not unlike this oscillator. I wonder if it would be possible to operate it as a balanced mixer simultaneously with oscillating. Then it could form the basis of a simple DC CW transceiver driving a crystal earpiece (with extra audio amplification needed).

Are you planning on entering the 2024 contest? If so how much power are you up to? Thanks DE KE5RJJ