Wow that is good going! These things are fun and they draw attention to the strange signal. The problem is that most guys have modern commercial rigs that have sharp filters and you never show yup in their passband.
Well, the little transmitter made its first contact coast to coast! Showing off on 7057 kHz, the little peanut whistle worked VE7SL first call. Thanks Steve!
Pause at the diagram you are interested in, and use the Windows scissors to capture an image. The quality when I am at full screen on the video is usually adequate.
Thanks, Mike. I set up a ~160VDC power supply on an inverted loaf pan using a a Heathkit 54-59 transformer with dropping resistor for the 2.5v heaters. .@@MIKROWAVE1
Many thanks for sharing these past three very interesting videos Mike. A while ago I built a similar 1930s style breadboard transmitter. It was a single 807 tube power oscillator transmitter and great fun to build and get working. I like the 1920s style and would like to build another breadboard transmitter in the future after my latest projects are finished. Really enjoyed watching these videos and a thumbs up to all. Well done...David M0DAD North East UK.
Hint - its working almost identically and at power - but a bit of chirp on 1 of them and 1 clean. So the lower Mu and emission of the older tube is a slight factor as expected. Converting over to tubing and upping voltage next.
Built my 1st Transmitter back in "65 teenager Borrowed a 50C5 from parent's Clock radio using 390 ohm 10 watt resistor (No Pwr transformer, Direct 120 vac Mains) 1/2 Wave Doubler on Plate & Screen, Tank Circuit 50 ohms matched all on 6" × 9" pine board.....>10 Watt RF Out == Plenty of Cheap & simple RF contacts DX range !!
Yes the old W5LET "Widowmaker"! I did a video on this with a Euro twist several years back. CAUTION you know HV can kill. th-cam.com/video/7n-52exDO3w/w-d-xo.html
Mike, I have used many times, the Windows Snipping tool to capture Schematics off of a TH-cam Video. Snip is a great tool to use when a web page is locked out from printing/saving/copying its content.
Note that there are legal (FCC) requirements for this type of transmitter. You seem to be scoffing at these requirements, likely because you feel the chances of being harassed by the FCC are minuscule. (true) They only go after really blatant violators.
Mike. I've sometimes wondered if Ross Hull's Australian ham licence was valid for use in America back in the twenties. Someone said to me he never had an American ham licence. I haven't been able to find any reference to him having had that. Considering the position he held when there, and the man's intelligence, I can only conclude he didn't require it.
That is a great question. I would assume that reciprocal operation is the answer. But this would not have precluded that he might have obtained a US call. My good friend Andrew VK3CV got WQ1S over here when I worked with him.
Hi Mike, I see you mention directly-heated valves including the LS5A at 0:43. I have an unused LS6A which I would love to use in this way. Will you explain at some point how to adapt the circuit for a directly-heated triode, please? Regards, Phil M1GWZ.
Wow that is an old valve all right and perfect to try in this. It has a 5V filament and can take quite high plate voltages. Assuming you have 5VAC you just need a pair of capacitors from each filament to ground like 0.01s. Then a pair of 22 to 50 Ohm 2W or higher power resistors off each filament tied together that form the center tap that goes to the key jack. That's it!
What would be the recommended technique to wrap the 1/4 inch copper tubing around a pipe? Clamp the pipe vertical and walk the tubing around the pipe or have the pipe horizontal on a work bench and rotate the pipe with a bar and feed the tubing?
Buy "soft" tubing and you can easily wrap it by hand; it's hardly stiffer than the #12 wire in the reference circuit in these videos. A little care will keep the tubing from collapsing as you wind it.
I am concerned about building this on a board due to my cats jumping on the table. Would building in an Atwater Kent model 35 metal chassis still work, or will it mess up the coupling or something?
Question: Assuming the DC components are battery powered and all wired up could the heating of the cathodes be done by non electrical means. Like with a custom built tiny propane torch tip or something similar?
I see a problem with a propane torch or any other flame heat source, in that the cathode you're trying to heat needs to be inside the evacuated envelope of the triode. A flame needs the oxygen from the air to burn... There's no good reason you couldn't use a battery source to light the filament, though. Many early receivers used a 2V lead-acid cell for filament power, and there were exchange programs at radio stores where you'd bring in your discharged filament cell and exchange it (and a little money, one presumes) for one fresh off the charger. The filament cell would last around a week in normal use (an hour or two each evening). This was for single tube receivers, but the filament in this single tube transmitter wouldn't use significantly more power (though the voltage is a little odd at 2.5 V for the Type 27). Two D size NiMH cells ought to do the job for a couple hours, at least. When I was quite small (around first grade, give or take) my parents had a multi-band tube radio that had provision for battery operation on two dry cell batteries: one 6V lantern type for the filaments (it was a 1950s design) and one 45V for the plates. The lantern battery was a pretty beefy 4-cell carbon zinc type, but the 45V B battery was hardly larger, despite having 30 cells -- and it would last ten times as long as the filament battery because the plate current was tiny. Unfortunately, I could never get them to buy a B battery (they may not have still been available in rural Idaho in 1965; any drug store would have had them ten years earlier).
I've worked 4 states on mine so far! It sounds pretty good! Thanks Mike!
Wow that is good going! These things are fun and they draw attention to the strange signal. The problem is that most guys have modern commercial rigs that have sharp filters and you never show yup in their passband.
Well, the little transmitter made its first contact coast to coast! Showing off on 7057 kHz, the little peanut whistle worked VE7SL first call. Thanks Steve!
Ok hvala i Vama takodje.
It would be nice if you had a website to download diagrams from for those of us that do not use facebook.
Here's one that doesn't use facebook.
Pause at the diagram you are interested in, and use the Windows scissors to capture an image. The quality when I am at full screen on the video is usually adequate.
It's a simple enough schematic to just draw while the video is on pause. Low tech, just like the project.
This series is wonderful! It follows in the legacy of Bob Heil's Pine Board AM Transmitter Project. Well done!! 73 DE K1TB
Thanks for watching. I will get the next one up Wed.
Thanks, Mike. I set up a ~160VDC power supply on an inverted loaf pan using a a Heathkit 54-59 transformer with dropping resistor for the 2.5v heaters. .@@MIKROWAVE1
Butterfly the capacitor to reduce sensitivity. Possibly have a fixed capacitor to get the correct value. Thanks for nice videos.
Great idea. Butterfly and Dual section caps are out there too! Differential Caps are a bit harder to find.
Many thanks for sharing these past three very interesting videos Mike. A while ago I built a similar 1930s style breadboard transmitter. It was a single 807 tube power oscillator transmitter and great fun to build and get working. I like the 1920s style and would like to build another breadboard transmitter in the future after my latest projects are finished. Really enjoyed watching these videos and a thumbs up to all. Well done...David M0DAD North East UK.
Wow a 807 Power oscillator. Now that will crack your fanny! er I mean Crystal.
Great Video and Information !!!
Thanks for watching!
Svaka cast doktore
Pozdrav cooking recepti. 73 Milan
Milan, hvala ti što si gledalac mog kanala.
Interesting videos! Thanks for putting them on TH-cam. 73's KG7UUJ
Great job on this series! Thanks Mike.
This should kick a few off the cliff that have wanted to try one.
Excellent, thank you Mike. Looking forward to seeing the Type 27 on the wood.😅
Hint - its working almost identically and at power - but a bit of chirp on 1 of them and 1 clean. So the lower Mu and emission of the older tube is a slight factor as expected. Converting over to tubing and upping voltage next.
Built my 1st Transmitter back in "65 teenager Borrowed a 50C5 from parent's Clock radio using 390 ohm 10 watt resistor (No Pwr transformer, Direct 120 vac Mains) 1/2 Wave Doubler on Plate & Screen, Tank Circuit 50 ohms matched all on 6" × 9" pine board.....>10 Watt RF Out == Plenty of Cheap & simple RF contacts DX range !!
Yes the old W5LET "Widowmaker"! I did a video on this with a Euro twist several years back. CAUTION you know HV can kill. th-cam.com/video/7n-52exDO3w/w-d-xo.html
👍Thank you sir.
Mike, I have used many times, the Windows Snipping tool to capture Schematics off of a TH-cam Video. Snip is a great tool to use when a web page is locked out from printing/saving/copying its content.
I am guilty this - to tell a story or show something clearly that I can not produce in a timely manner.
Thanks Mike for the contacts during the BK Contest !
Hope to run into you on the Linc Cundall coming up!
Note that there are legal (FCC) requirements for this type of transmitter. You seem to be scoffing at these requirements, likely because you feel the chances of being harassed by the FCC are minuscule. (true) They only go after really blatant violators.
Yes guilty. But I really scoff at obsessing on the miniscule at the risk of discouraging experimentation and learning by newcomers to the hobby.
Mike. I've sometimes wondered if Ross Hull's Australian ham licence was valid for use in America back in the twenties. Someone said to me he never had an American ham licence. I haven't been able to find any reference to him having had that. Considering the position he held when there, and the man's intelligence, I can only conclude he didn't require it.
That is a great question. I would assume that reciprocal operation is the answer. But this would not have precluded that he might have obtained a US call. My good friend Andrew VK3CV got WQ1S over here when I worked with him.
Awesome build .Wish I could get my radio licence in Canada but it seems there is souch red tape to get your armature radio licence
Passing (70%) a multiple choice exam of 100 questions and 60 Canadian I thought to get started?
Hi Mike, I see you mention directly-heated valves including the LS5A at 0:43. I have an unused LS6A which I would love to use in this way. Will you explain at some point how to adapt the circuit for a directly-heated triode, please? Regards, Phil M1GWZ.
Wow that is an old valve all right and perfect to try in this. It has a 5V filament and can take quite high plate voltages. Assuming you have 5VAC you just need a pair of capacitors from each filament to ground like 0.01s. Then a pair of 22 to 50 Ohm 2W or higher power resistors off each filament tied together that form the center tap that goes to the key jack. That's it!
@@MIKROWAVE1 Thanks, Mike! M1GWZ
What would be the recommended technique to wrap the 1/4 inch copper tubing around a pipe? Clamp the pipe vertical and walk the tubing around the pipe or have the pipe horizontal on a work bench and rotate the pipe with a bar and feed the tubing?
Buy "soft" tubing and you can easily wrap it by hand; it's hardly stiffer than the #12 wire in the reference circuit in these videos. A little care will keep the tubing from collapsing as you wind it.
There are some great websites that show how to do this. This is my friend Steve's site. qsl.net/ve7sl/tnt.html
Great Link, Thank You !!!@@MIKROWAVE1
Can you use a Grid Dip Meter to check the frequency that your coil winding will resonate at ?
Great idea!
I am concerned about building this on a board due to my cats jumping on the table. Would building in an Atwater Kent model 35 metal chassis still work, or will it mess up the coupling or something?
MEOW! Building it into a chassis of metal will be great as long as the big coil is an inch away from the metal sides of the box.
🏆🏆🏆🇧🇷🇧🇷🇧🇷
CQ Contest?
Question: Assuming the DC components are battery powered and all wired up could the heating of the cathodes be done by non electrical means. Like with a custom built tiny propane torch tip or something similar?
I see a problem with a propane torch or any other flame heat source, in that the cathode you're trying to heat needs to be inside the evacuated envelope of the triode. A flame needs the oxygen from the air to burn...
There's no good reason you couldn't use a battery source to light the filament, though. Many early receivers used a 2V lead-acid cell for filament power, and there were exchange programs at radio stores where you'd bring in your discharged filament cell and exchange it (and a little money, one presumes) for one fresh off the charger. The filament cell would last around a week in normal use (an hour or two each evening). This was for single tube receivers, but the filament in this single tube transmitter wouldn't use significantly more power (though the voltage is a little odd at 2.5 V for the Type 27). Two D size NiMH cells ought to do the job for a couple hours, at least.
When I was quite small (around first grade, give or take) my parents had a multi-band tube radio that had provision for battery operation on two dry cell batteries: one 6V lantern type for the filaments (it was a 1950s design) and one 45V for the plates. The lantern battery was a pretty beefy 4-cell carbon zinc type, but the 45V B battery was hardly larger, despite having 30 cells -- and it would last ten times as long as the filament battery because the plate current was tiny. Unfortunately, I could never get them to buy a B battery (they may not have still been available in rural Idaho in 1965; any drug store would have had them ten years earlier).
Yes I imagine - as long as the rod was protruding through the seal so you heat it externally. But that would likely break the seal!
I was thinking something like that about 10 minutes later. Doh! @@SilntObsvr
When is the 2029 transmitter? 😊😊
That will require the vintage fluidity interoctor first seen in 2340. Those things are getting scarce.
@@MIKROWAVE1 🤣😅☺️
73's🎙KD9OAM🎧📻🚧