Anatomy of a 30 watt 7 MHz CW regenerative transceiver (and a DX demonstration)

Circuit description of a homebrew 30 watt 7 MHz CW regenerative receiver - transmitter. Contains demonstration of DX contact made with it.
Contents
0:00 Introduction
0:37 Transceiver description
1:20 Receiver in more detail
1:51 Transmitter in more detail
4:06 Circuit description
10:05 Reference for transmitter circuit
10:26 On air
14:19 Summary
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[@ASCIITerminal]

Nice work! I am not sure what is more impressive. The transceiver, or your ability to send CW without sidetone!

[@Paul_VK3HN]

Nice job Peter, things in the RF power amp stage actually get simpler when you can use a 30v rail!

[@frycz66]

Piotr, My name is Robert SP5RF and I am a ham radio from Poland (Central Europe). I am at the SP5KAB club and we often discuss your ideas, constructions and generally a simple minimalist way of practicing our hobby. What you do is very inspiring and often "puts us up" - I don't know if this idiom is well translated. :) Just when we want to go into another hardware race, another screen, a new more powerful processor, a new microphone with triple echoes, we realize that in Australia there is Piotr who on a simple antenna from a rod and yaesu FT 817 makes SSB communication with England on 400mW !! Thank you for this inspiration. There are many channels on YT, but you break through with the simplicity of the message, naturalness, and the consistent promotion of QRP refined in its simplicity. Keep doing it !! We greet you warmly !! 73!

[@vk3ye]

Thanks Frycz for your kind words - glad you enjoy the videos!

[@JamesCutlervk2tim]

That’s an impressive build, but even more impressive is how well you explained the circuit function. Very well done! 73 from VK2TIM

[@boweandrew3]

These are super videos simply amazing Peter great job

[@raafatalheety826]

Very good vk3ye.

[@Radionut63]

Awesome job on that radio!

[@IvanPassos]

homebrew transceiver cw excellent peter...

[@IvanPassos]

74HC04 between the pin 11 and 10 and the pin 14 will BC558 colector key transmitter :)

[@bill-2018]

That's a nice looking front panel layout Peter, always good to have things looking right. Nothing I ever built had sidetone either. 18 years using all H.F. ssb/cw tx/rx 6 Watts out but got FT817 recently because of small size for portable, so h/b rig I'm thinking of putting on 70 MHz and 5 MHz, I don't need two H.F. rigs. Have a 61BT one valve CW xtal tx on 5.262 MHz running 1.6 Watts out. I've successfully used Veroboard for 7 MHz projects. Recently dug out my 1.910 MHz xtal single BFY51 transistor tx built about 40 years ago.

[@bill-2018]

73 Peter. Bill, G4GHB.

[@marklowe7431]

Incredible

is there a easy way of switching between two bands and what components would you be able to use for multiple bands?

[@SpectreOZ]

The spot alignment feature is a clever solution/feature nice work Peter, BTW those knobs to the extreme right of the fascia look familiar perhaps something recycled from a HMV radio or similar circa 1970's :)

[@vk3ye]

+SpectreOZ Yes I go to a lot of trouble with knobs. Even pulling them off other projects to ensure that I have sufficient number to ensure they match and fit in with the item's decor.

[@SpectreOZ]

+vk3ye I will confess to relieving parted out Electronics for their dials/knobs as well... everything is useful more than once around.

[@breadfan3415]

I love watching your projects Peter! Is the RX circuitry exactly the same as the original one (f5lvz or so?) ??? Any links or PDFs available? I would like to give it's go. Thx.73!

[@raafatalheety826]

Good luck

[@user-re9rg3rk5m]

May the same generator (one for tx and rx) be better?

[@edbeckerich3737]

Did you have a reason for changing the values of your RC audio filter from W7ZOI web link?

[@vk3ye]

Probably to suit available components

[@raafatalheety826]

Thanks for you peter I want ssb the same transceiver this .73 from baghdad yi1hxh.

[@scharkalvin]

I suppose with vxo tuning a regenerative receiver would work acceptably, but I'd probably rather build a simple superhet design using SA610's. I'd probably use an Si5351 and a simple arduino as the vfo, if for no other reason than to be able to cover the entire 40 meter band, and have digital frequency readout. The cost of doing this is actually not much more than a vxo once you add the required tuning capacitor and vernier dial. (Two line LCD's or OLED displays from China on ebay are very inexpensive, possibly less than the cost of a NOS Japanese vernier dial.) I very much like the transmitter design. The inverter stages actually don't provide a truly balanced push pull drive (very close, but no cigar), however with a class C final (what do you set the resting current to with the bias adjust?) it really doesn't matter since you don't need linear drive.

[@weirdsciencetv4999]

Is it possible to make a hybrid superheterodyne/regen receiver? Where you translate the incoming signal to an IF, then have regeneration on the IF stage?

[@vk3ye]

Yes and common practice in the past.

[@weirdsciencetv4999]

@@vk3ye i love your designs!

[@engdroidyu9487]

74hc04 work for what?

[@johnrees44..G4EIJ]

Hi from the U.K., Peter...A brilliant build and video! Are the details included in any of your books, please? I look forward to more of your home brews!! A rarity these days..Cheers... John.. G4EIJ

[@vk3ye]

Hi John - Glad you enjoyed it. None of my books include transmitter and receiver circuits.

[@johnrees44..G4EIJ]

Ok...thank you for response, Pete..I look forward to spending time with my feet up, watching all your vids!😊 Happy new year to you! 73...John G4EIJ

[@letitrotfuckit]

Very Nice Work! I tried making similar stuff, but I never got any contacts. This would be a even better rig if it is tunned to 10 or 11 meters, the glory bands where I get 2 or three contacts a day. 73 K9RUSS

[@t76d777f6d]

Hey vk3ye, I'm new to amateur radio and want to do DX CW on a rig that will give me as much key time as possible. A lot of kits are "QRP" but as a beginner I am concerned this is not the best choice for me to start. This will be my first piece of equipment. I am licensed on the HF bands. I have experience building kits, but not a lot of experience designing electronics. Can you please guide me towards a solution? Any help is much appreciated. An opinion dump would be fantastic, you own't offend me. Thank you.

[@vk3ye]

+taiden Quick way: Build a QRP kit and then add an amplifier (either kit or built-up). Long way: Buy all 4 of VK3XU's books. Build several projects from scratch in it. Then attempt high higher power rigs or amplifiers.

[@t76d777f6d]

+vk3ye Cheers, thank you. Are you partial to any particular qrp kits or amps?

[@vk3ye]

+taiden Haven't built a decent CW QRP kit for ages. Check eham for kit reviews. Any kit must have these three features kzbin.info/www/bejne/npucp5RvgbJ1bZo

[@t76d777f6d]

+vk3ye Cheers, I watched that video and really enjoyed it. My problem is I am having a hard time interrogating the kits over the internet. It seems like a digital interface would be no good for frequency agility, especially like the MTR, would be poor for frequency agility, and a crystal based would be worse. I am not sure how to determine if offset is a common feature or if I should have a second knob for it. And as for transmit/receive switching I honestly thought it was automatic until I saw your video. I do not expect you to hold my hand, just trying to drill down to some options. Thanks

[@vk3ye]

+taiden Try this list of QRP kits www.qrptransceiver.com/#qrp-transceiver-kits

[@iceberg789]

how can anyone understand anything from those fast beeps ?

[@donsolano8830]

After trying to build a superhet receiver using two ne612 ic's until now. I'm beginning to think id rather build a regen..

[@kq6up]

These little projects are super cool. The only thing is buying parts one at a time from the local electronics store (yes we still have brick and mortar) ends up costing an arm an a leg. I do have somewhat of a junk box, but it is so disorganized and scattered. What is your advice for getting parts like this on the cheap? Also even getting them 1sie 2sie from digikey still ends up costing a lot. It looks like you scrounge everything, and I like that sticks with your minimalism. Do you have advice on scrounging for parts to build kits? If you have a video or a book about this, I would be happy to watch or purchase. 73 de Chris KQ6UP SK ..

[@vk3ye]

Chris - some articles on my website discuss getting parts. vk3ye.com/technical/index.htm

[@riottaba]

wot no sidetone

[@jeromegrzelak8236]

TRULEY INSPERATIONAL KG6MN

[@PU4YJS]

Excelent, vk3ye! Homebrew mounted your circuit, the best nice inspiratio. PU4YJS/Daniel

[@AndrewMurphy8383]

CANT get the book unless you are member of the club that is crying shame to