This is a beautiful piece, thank you for keeping it up and sharing your work with us. Really love those windings in it, fascinating how magnetism works.
Thanks very much for your video. It's interesting to see how these radio sets used to work. I am quite amazed you have kept this one running especially the fact that it uses such old valves.
Thanks 🙏 for watching and subscribing. I’m glad you enjoyed the video and hope you enjoy my other videos. Ham radio and antique radios are one of my passions. I just turned off that radio before I saw your comment. I listen to them daily when I’m home and not traveling. Thanks again take care 😃
Thanks for subscribing and watching. I’m glad you enjoyed the video. Please check out my other antique radio videos. My home brew 6V6/807 transmitter. And A/B power supply battery eliminator. The National SW3 is an awesome receiver. Take care my friend KA1VMW.
Thank you Mark for doing the video on this radio. I especially like seeing you tune it, the internal workings, and the differences between the tube types. Before watching your video, I pulled the schematic, figured out how it worked, and determined what components the front panel knobs were connected to. The only thing I could not figure out is, what do those thumb wheels below the variometers connect to? From pictures, they seem to be part of the variometer assembly. I had no idea this was a one tube receiver. Alfred Grebe was quite advanced in his designs for that time period. His antenna input circuit resonates antenna capacitance to improve receiver gain. The variometers are used in place of tuning capacitors, found in later receivers. In this circuit, they are actually resonating the tube grid and plate capacitance to accomplish the tuning. However, due to the relatively high grid-to-plate capacitance (Miller's Effect), the circuit is guaranteed to oscillate when both the grid and plate are tuned to the same frequency. That's why you must detune the plate to stop the circuit from oscillating. Regenerative receivers are always radiating the signal they are tuned to. Obviously, more signal is being radiated the closer you get to the oscillation point. This is why they act like they have a BFO (Beat Frequency Oscillator) when receiving CW and SSB. Operating this radio in the early 1920's must have been instantly addictive.
The early UV200 and the UV201 drained 1 amp on the Filament. That’s why early radios had many audio jacks so you could eliminate any tubes not needed. First jack detector with headphone use. 2nd jack detector and one stage of audio headphone or speaker if you have a strong signal. 3rd jack detector with two stages of audio driving a speaker even for weak signals. As you noted the CR-8 has a detector tube in the box. The earlier CR-3 the detector tube was in the amplifier box. The amplifier I’m using is a home-brew with period parts. The vernier knobs have a steel shaft with a rubber tire behind the main tuning knob. The grid variometer is the station selector tuning the plate variometer is for regeneration. The small knob to the right is the rheostat for the filament. The small knob to the right of the rheostat is a switch to change the wavelength (band). It adds or removes condensers from the circuit. As you noted the variocoupler is a taped coil with a rotor coil to tune the ANT. There are grounded metal plates behind the variometers and variocoupler to eliminate hand capacitance. Thanks again 🙏. 73’s my friend
@@curlyzim1 Thanks Mark for the detailed explanation, which really helps my understanding. With all the tube radios I have restored, none have been 1920's era, (only 1930+) which are the most interesting. I actually have never seen that many for sale and, of the ones I have seen, the seller wants too much money for something requiring a major restoration effort. I did work with an electronic Tech in the 1980's who I believe was born about 1920. He, along with some of his buddies in the same neighborhood, built home brew regenerative recievers for use primarily on the AM broadcast band. If two of them were operating at the same time and found each other's Beat notes, they would communicate by Morse Code, using the antenna connection as a Key. With everyone in the neighborhood picking up this interference, I am confident this is how Radio Amateurs acquired the name of "Hams". 73! Bill Harris, AC8AQ
@@qwertykeyboard5901 Thanks 🙏 for the nice comments and watching. Please check out my other vintage radio videos under my vintage radio playlist. 73’s my friend 👋
![Electronic Circuitry Diagnosis And Fault Finding! [Repair]](http://i.ytimg.com/vi/LC7OjuYAOQE/mqdefault.jpg)
This is a beautiful piece, thank you for keeping it up and sharing your work with us.
Really love those windings in it, fascinating how magnetism works.
Your two stage homebrew amplifier works well. Now I know why the horn loud speaker played loud in on of your previous videos. Very nice.
Thank you my friend 😃. Have a very Happy Thanksgiving 🦃. And all the best to you and your family 👋
ive always wanted an old wood cabinet radio/record player. but i sure do not want to move it!
Thanks very much for your video. It's interesting to see how these radio sets used to work. I am quite amazed you have kept this one running especially the fact that it uses such old valves.
Thanks 🙏 for watching and subscribing. I’m glad you enjoyed the video and hope you enjoy my other videos. Ham radio and antique radios are one of my passions. I just turned off that radio before I saw your comment. I listen to them daily when I’m home and not traveling. Thanks again take care 😃
Thanks for preserving this interesting piece of history.
Thanks 🙏 for subscribing 👍 and the nice comment. I’m glad you enjoyed the video.
That must've been one of the first commercially available ones of its time! Seriously old tech.
Excellent. 102 years ago. Nikola Tesla one of the greatest would have been around 65. We've come a long way
thanks have built a few regen receivers have wanted a Grebe
am lucky have a nice National SW3 Thrill Box with PS and a few coil sets
Thanks for subscribing and watching. I’m glad you enjoyed the video. Please check out my other antique radio videos. My home brew 6V6/807 transmitter. And A/B power supply battery eliminator. The National SW3 is an awesome receiver. Take care my friend KA1VMW.
Thank you Mark for doing the video on this radio. I especially like seeing you tune it, the internal workings, and the differences between the tube types.
Before watching your video, I pulled the schematic, figured out how it worked, and determined what components the front panel knobs were connected to. The only thing I could not figure out is, what do those thumb wheels below the variometers connect to? From pictures, they seem to be part of the variometer assembly.
I had no idea this was a one tube receiver. Alfred Grebe was quite advanced in his designs for that time period. His antenna input circuit resonates antenna capacitance to improve receiver gain. The variometers are used in place of tuning capacitors, found in later receivers. In this circuit, they are actually resonating the tube grid and plate capacitance to accomplish the tuning. However, due to the relatively high grid-to-plate capacitance (Miller's Effect), the circuit is guaranteed to oscillate when both the grid and plate are tuned to the same frequency. That's why you must detune the plate to stop the circuit from oscillating.
Regenerative receivers are always radiating the signal they are tuned to. Obviously, more signal is being radiated the closer you get to the oscillation point. This is why they act like they have a BFO (Beat Frequency Oscillator) when receiving CW and SSB.
Operating this radio in the early 1920's must have been instantly addictive.
The early UV200 and the UV201 drained 1 amp on the Filament. That’s why early radios had many audio jacks so you could eliminate any tubes not needed. First jack detector with headphone use. 2nd jack detector and one stage of audio headphone or speaker if you have a strong signal. 3rd jack detector with two stages of audio driving a speaker even for weak signals. As you noted the CR-8 has a detector tube in the box. The earlier CR-3 the detector tube was in the amplifier box. The amplifier I’m using is a home-brew with period parts. The vernier knobs have a steel shaft with a rubber tire behind the main tuning knob. The grid variometer is the station selector tuning the plate variometer is for regeneration. The small knob to the right is the rheostat for the filament. The small knob to the right of the rheostat is a switch to change the wavelength (band). It adds or removes condensers from the circuit. As you noted the variocoupler is a taped coil with a rotor coil to tune the ANT. There are grounded metal plates behind the variometers and variocoupler to eliminate hand capacitance.
Thanks again 🙏. 73’s my friend
@@curlyzim1 Thanks Mark for the detailed explanation, which really helps my understanding.
With all the tube radios I have restored, none have been 1920's era, (only 1930+) which are the most interesting. I actually have never seen that many for sale and, of the ones I have seen, the seller wants too much money for something requiring a major restoration effort.
I did work with an electronic Tech in the 1980's who I believe was born about 1920. He, along with some of his buddies in the same neighborhood, built home brew regenerative recievers for use primarily on the AM broadcast band. If two of them were operating at the same time and found each other's Beat notes, they would communicate by Morse Code, using the antenna connection as a Key. With everyone in the neighborhood picking up this interference, I am confident this is how Radio Amateurs acquired the name of "Hams".
73! Bill Harris, AC8AQ
I love how these early radios look insane.
@@qwertykeyboard5901 Thanks 🙏 for the nice comments and watching. Please check out my other vintage radio videos under my vintage radio playlist.
73’s my friend 👋