Yes, it is a very good contact. By creating such a standardized pinout, I can use the power for many new designs. I also recommend this to other designers of ham radio equipment.
We have in the US Nuvistors .This are small vacuum tubes that were designed for portable communications ..They are very small tubes ,and they last forever ..
Brilliant project, as always, I am precisely working on a similar project but for AM, using a hexode triode ECH81 as oscillating and modulating tube, and with excellent results. 73 of EA1FLL 😊
Thanks for the comment. It is not optimal with minijack. Can't find anything else that small. It withstands the tension well. There is a danger if you touch one with voltage. But since I use the ring for 250 volts, the current will always go the shortest way to the tip or gnd in the innermost part. But I never turn on the power until everything is mounted.
Wonderful!! I am now practicing my CW once again. I live too far from you, but maybe some day we can have a QSO! You are a good man to help keep older radios and tube technology alive! I have spent more time lately in the CW bands! Especially 80 and 40 meters. Thanks!
I have a 1960s Japanese-made Univox guitar amp that uses a pair of 6AQ5 output tubes. Nice sounding tube for audio applications. Basically a miniature 6V6.
@@LA6NCA Good idea! My father was a WW2 submarine officer on HMS Torbay, and Torbay was on one patrol off northern Norway covering an artic convoy. / My mother's war was never spoken of in her lifetime, but she was involved with French Section SOE, which I discovered with a bit of detective work. So she was part of the organisation that prepared agents to go to France, equipped with radios such as those you take such good care of. / And I am aware of the courage of Norwegians under the heel of the German jackboot, for which I have a lot of respect. / Plus I have Viking blood in me, as I have Macleod Scottish highland blood in me, which it is said leads back to King Harald Hardrada of Norway, killed at the Battle of Stamford Bridge in 1066. Best wishes, Zen
Very nice. I built it but I only had 12AU7 tubes at the time. But since the 12AU7 is a twin triode tube, only one tube was needed. The performance wasn't great but it worked to some extent. It could be because the tube is not meant to be used at such frequencies, or that I used 160v DC instead kg 250v. Update, I designed a new HV power supply that uses 12.6v for the thing and it outputs 350v DC. But the problem is that it takes 10 minutes for the thing to reach that, charging up the capacitors. And once I press the key, the voltage drops off quickly. It would be a nice video to show off your HV powersupply.
Thanks for the excellent video Helge. Have you published the schematic or other construction information about your switched mode power supply? That looks very interesting and useful.
Very well explained, thanks. I really like the care taken in grounding and decoupling. You are an experienced Ham, no doubt 😁 May be a little affraid of the 300V on the jack connector. I would certainly put my fingers on it one day or another 🤣. 73, F1SOC
Hi Helge, and thanks for the great video. I've been playing with similar MOPA style valve TXs for a while now and learning a lot. One thing that I tend to do is run from small Chinese SMPS boards which can be quite noisy. I'm really interested in your PSU set up. Are you using an TL494 driving fets and a mains transformer in reverse ? Would be really interested in a video on that. My current project is a small TRF RX and MOPA TX all based on Battery Valves. Hoping to do some Valve SOTA activity :-) 73s and GL
Thanks for the comment. I am using a 4046 oscillator driving two mosfet transistors. I can post some documentation on my internet site about it. www.laud.no/ww2/
@@LA6NCA hi. Thanks for the reply. That would be interesting to see. I did take a look at your website but only found your low current battery replacement.
Beautiful work... very nice transmitter. I didn't try anything with tubes yet. I must learn a little more about it... but I know for sure I want to have fun with this. Thank you for sharing this nice project. 73 DE YO6DXE.
I love these minimal builds. If you crash on a remote island it's good to know you can call for help even if you can't find a single transistor :) 73 de OZ1AN
Nice job, with a big whoopsie. Putting 250 volts through a 3.5mm plug is a bad idea in at least 4 ways. I’m sure you can think of at least two of them.
I have restored lots of real spy radios from WW2 and the Cold War. Have also made a number of videos about them. For me, this is a design in this "spirit". I don't really have any experience with QRP radio amateur QSO's beyond what I have done with these real spy radios.
every single volt is under the hood if well designed as it is also the case with any electric appliances. I'd be more worried about burning the finger tips.
