Nice. A quick peek through some of the videos reminds me of when I was a youngen and trying to learn. Had no money so I would strip old transistor radios and stuff for components and build on plywood as my proto boards :)
You remind me of when I was winding coils on pieces of 2X4's. 60 years latter my lab is full of HP, Agilent, Keithley, and Fluke gear. And now, with transceivers of all vintages on my shelves and desks I'm back to building gear on scraps of wood, and having a ball. But admittedly it's now a lot easier to tune the circuits than back when I did it all by ear. :)
@@johnwest7993 Cheers. I am only recently getting back into it at 58. But I am more Logic and Audio inclined than RF. I'm living with chronic heart failure and back on a tight budget. You should see 12V 21W array of 10 globes I made up as a cheap load tester lol I had a lot of fun making that :) > I had fun on plywood. For smaller projects I would dig up some old kitchen cabinet laminate which worked well. > These days I have packs of breadboard and veraboard, and use acrylic for cases. But I still like that classic wood grain feel :) I was looking at that speaker box and getting all excited lol
Bill - a tip on this. I'd check the audio bandpass characteristics. There is excessive hiss and audio is a bit thin, cutting off bass. Consider increasing the value of series capacitors in the audio stage and putting some capacitors in parallel at key points (eg across volume control and other audio stages). Depending on impedance around 10nF will help. While the shape won't be as tight as a transistor or IC low pass audio filter you should still get some improved signal to noise ratio with a better audio bandpass characteristic. Maybe consider some switches to switch in various parallel capacitors depending on whether you want the top cut or not - you don't want the top cut to be too harsh otherwise you lose sparkle and the audio sounds muddy, with readability falling on weak signals.
Thanks Peter. I think it sounds fine -- its transfer through the internet may be making it sound bad. I did check the audio bandpass characteristics and in fact changed the emitter bypass caps from 47 uF to 470 uF for better audio. It helped a lot. As for the hiss, again this may be an internet/TH-cam thing. I always check to see if the hiss is coming from the receiver or from the universe. In this case, it is the universe! Band noise. When I disconnect the antenna, the hiss disappears. Thanks for the recommendations, but our goal here was to develop a VERY simple receiver. So we don't have any feedback, we don't have a push pull amp at the final etc. These things might have been nice, but they would have added complexity, and that was something that we were (and are!) trying to avoid. We would be honored if the Wizard of Melbourne (you!) built one of these receivers (please first build it our way -- mods can come later ) and then did a video on it. 73 Bill
Do you know how much trouble you caused with the HRWB homebrew challenge! Everyone is building one or talking about it now. - Well Played Sir! - hahaha I'll be one of those people building one too! - smile -thanks for sharing -73
My apologies if I missed it on another video, but approximately how much current does the receiver draw with headphones? BTW, I'm sometimes an appliance operator, but less and less of one as I learn more and more about RF. There is no end to learning about RF. Your channel, other similar channels, and my books help me do just that. If I'm not mistaken, that learning process is what the amateur radio hobby is all about. It's not Super-CB. Thank for your channel and your simple, very inexpensive, but good performing gear.
That sounds a lot like SSB.I listen to a lot of SSB via webSDR.AND I mainly camp out on 75/80 meters where the freewheelers net is nightly Sunday through Friday at 22 to 00 hundred hours “1700 to 1900 UTC”. On 3916 kHz lower sideband.
I don't know. I see that many simple QRP receivers use a 10k pot in this role, so I used one here. I just reached into my junk box and picked out a 10k pot. I don't even know what the taper is. It works. But you can live without it. We recommend NOT making this mod on the original receiver. Build the receiver first, then add extras like the RF gain control. Then you can experiment to see if there is an optimal pot value and taper. 73 Bill
@ hey Bill, thanks for the reply ( you are up early!). I’ve posted several questions for Dean on exactly what is the actually correct original design in the comments to video blog 255. I have most of the contingencies covered but waiting for January. :) 73 ol’ man es tnx agn
@@jertres2887 I am in the Atlantic time zone, so it is not really that early. I was thinking that we might not have been as precise about the parts as many would have liked, becasue we often just reach into our junkboxes and find something that will work at the indicated spot in the circuit. This is real homebrewing -- this is not kit assembly, nor is there a BOM that keeps all the parts neatly specified. This is where it is important to understand what the circuit is doing and what the part is doing. So a bypass cap that is .2 uF 25V could easily substitute for a cap (from the schematic) that is supposed to be .1uF 16V. But the caps that determine the frequency of the oscillator are a different story, right? When I said that people should build the design that we put out, I was really talking about the overall architecture: BP filter, PTO, diode ring mixer, common emitter AF amp. I wasn't really suggesting that people build with EXACTLY the parts that we used. A lot of substitution takes place on the workbench in true homebrewing. 73 Bill
I get that, and probably most of the guys who say “mine didn’t’ work” thought that’s all they were doing, it’s kind of a fuzzy line between making do with what you’ve got and “changing” the design. I have been very guilty of trying to improve something and messing it up. I’ve kind of taken what you posted as the nominative “ideal” version, like maybe it was perfected in ltspice, and these are the closest values for what can be obtained without heroic effort… or… could be it’s what you could get reasonably easily that looked close enough. I don’t know and what I’d really like to be sure of is that there are no typos. For Dean, it would be nice to start with a design where you can say if you build it just like this it will work. And maybe some guidance about what parts might be critical and where pretty close will probably do. N3fjz made some changes. Even when done correctly variances like in transistor gain can make the “properly” constructed not behave as wanted.
Me refiero a lo que presenta en el video, no a lo que se puede esacuchar. Ni siquiera muestra un diagrama de bloques, ni una explicación de como funciona, ni cuales son sus especificaciones tecnicas !!!
Daniel: We have on the internet YEARS of schematics, pictures, videos, diagrams and tutorials on this receiver. Just take a look at the SolderSmoke blog. Or: hackaday.io/project/190327-high-schoolers-build-a-radio-receiver Or: www.remmepark.com/circuit6040/SolderSmoke-DCR/SolderSmoke-DCR.html#AUDIO_AMP In this video, I just hoped to show what the receiver was capable of. To bad you found it so lacking in what you were looking for. Perhaps the links above, or maybe Google would help. Bill
That sounds better than I ever recall my FRG-7 being!
Nice. A quick peek through some of the videos reminds me of when I was a youngen and trying to learn. Had no money so I would strip old transistor radios and stuff for components and build on plywood as my proto boards :)
You remind me of when I was winding coils on pieces of 2X4's. 60 years latter my lab is full of HP, Agilent, Keithley, and Fluke gear. And now, with transceivers of all vintages on my shelves and desks I'm back to building gear on scraps of wood, and having a ball. But admittedly it's now a lot easier to tune the circuits than back when I did it all by ear. :)
@@johnwest7993 Cheers. I am only recently getting back into it at 58. But I am more Logic and Audio inclined than RF.
I'm living with chronic heart failure and back on a tight budget. You should see 12V 21W array of 10 globes I made up as a cheap load tester lol I had a lot of fun making that :)
>
I had fun on plywood. For smaller projects I would dig up some old kitchen cabinet laminate which worked well.
>
These days I have packs of breadboard and veraboard, and use acrylic for cases. But I still like that classic wood grain feel :) I was looking at that speaker box and getting all excited lol
Cant beat the sound of direct conversion receiver, you feel immersed in sound
Bill - a tip on this. I'd check the audio bandpass characteristics. There is excessive hiss and audio is a bit thin, cutting off bass. Consider increasing the value of series capacitors in the audio stage and putting some capacitors in parallel at key points (eg across volume control and other audio stages). Depending on impedance around 10nF will help. While the shape won't be as tight as a transistor or IC low pass audio filter you should still get some improved signal to noise ratio with a better audio bandpass characteristic. Maybe consider some switches to switch in various parallel capacitors depending on whether you want the top cut or not - you don't want the top cut to be too harsh otherwise you lose sparkle and the audio sounds muddy, with readability falling on weak signals.
Thanks Peter. I think it sounds fine -- its transfer through the internet may be making it sound bad. I did check the audio bandpass characteristics and in fact changed the emitter bypass caps from 47 uF to 470 uF for better audio. It helped a lot. As for the hiss, again this may be an internet/TH-cam thing. I always check to see if the hiss is coming from the receiver or from the universe. In this case, it is the universe! Band noise. When I disconnect the antenna, the hiss disappears. Thanks for the recommendations, but our goal here was to develop a VERY simple receiver. So we don't have any feedback, we don't have a push pull amp at the final etc. These things might have been nice, but they would have added complexity, and that was something that we were (and are!) trying to avoid. We would be honored if the Wizard of Melbourne (you!) built one of these receivers (please first build it our way -- mods can come later ) and then did a video on it. 73 Bill
Do you know how much trouble you caused with the HRWB homebrew challenge! Everyone is building one or talking about it now. - Well Played Sir! - hahaha I'll be one of those people building one too! - smile -thanks for sharing -73
😅😅😅😅
Oh, we know, we know! Great that you are going to build it. Send progress pictures!
It sounds like the KnightKit OceanHopper regenerative receiver from the ‘60.
My apologies if I missed it on another video, but approximately how much current does the receiver draw with headphones?
BTW, I'm sometimes an appliance operator, but less and less of one as I learn more and more about RF. There is no end to learning about RF. Your channel, other similar channels, and my books help me do just that. If I'm not mistaken, that learning process is what the amateur radio hobby is all about. It's not Super-CB. Thank for your channel and your simple, very inexpensive, but good performing gear.
John: I never really looked at this, but I measured about 40 milliamps, with a small speaker attached. 73 Bill
That sounds a lot like SSB.I listen to a lot of SSB via webSDR.AND I mainly camp out on 75/80 meters where the freewheelers net is nightly Sunday through Friday at 22 to 00 hundred hours “1700 to 1900 UTC”. On 3916 kHz lower sideband.
For the “RF Gain” attenuator pot, is 10 k optimal? Would a smaller pot be sufficient? And does the taper matter at all? Thanks!
I don't know. I see that many simple QRP receivers use a 10k pot in this role, so I used one here. I just reached into my junk box and picked out a 10k pot. I don't even know what the taper is. It works. But you can live without it. We recommend NOT making this mod on the original receiver. Build the receiver first, then add extras like the RF gain control. Then you can experiment to see if there is an optimal pot value and taper. 73 Bill
@ hey Bill, thanks for the reply ( you are up early!). I’ve posted several questions for Dean on exactly what is the actually correct original design in the comments to video blog 255. I have most of the contingencies covered but waiting for January. :) 73 ol’ man es tnx agn
@@jertres2887 I am in the Atlantic time zone, so it is not really that early. I was thinking that we might not have been as precise about the parts as many would have liked, becasue we often just reach into our junkboxes and find something that will work at the indicated spot in the circuit. This is real homebrewing -- this is not kit assembly, nor is there a BOM that keeps all the parts neatly specified. This is where it is important to understand what the circuit is doing and what the part is doing. So a bypass cap that is .2 uF 25V could easily substitute for a cap (from the schematic) that is supposed to be .1uF 16V. But the caps that determine the frequency of the oscillator are a different story, right? When I said that people should build the design that we put out, I was really talking about the overall architecture: BP filter, PTO, diode ring mixer, common emitter AF amp. I wasn't really suggesting that people build with EXACTLY the parts that we used. A lot of substitution takes place on the workbench in true homebrewing. 73 Bill
I get that, and probably most of the guys who say “mine didn’t’ work” thought that’s all they were doing, it’s kind of a fuzzy line between making do with what you’ve got and “changing” the design. I have been very guilty of trying to improve something and messing it up. I’ve kind of taken what you posted as the nominative “ideal” version, like maybe it was perfected in ltspice, and these are the closest values for what can be obtained without heroic effort… or… could be it’s what you could get reasonably easily that looked close enough. I don’t know and what I’d really like to be sure of is that there are no typos. For Dean, it would be nice to start with a design where you can say if you build it just like this it will work. And maybe some guidance about what parts might be critical and where pretty close will probably do. N3fjz made some changes. Even when done correctly variances like in transistor gain can make the “properly” constructed not behave as wanted.
Do you have the circuit? PU2-UBB, São Paulo, Brazil
Lots of details in the links in the TH-cam video description.
Y esto es todo??? Nada mas ????
No entiendo. Me parece que puedes escuchar a muchas cosas. De acuerdo?
Me refiero a lo que presenta en el video, no a lo que se puede esacuchar. Ni siquiera muestra un diagrama de bloques, ni una explicación de como funciona, ni cuales son sus especificaciones tecnicas !!!
Daniel: We have on the internet YEARS of schematics, pictures, videos, diagrams and tutorials on this receiver. Just take a look at the SolderSmoke blog. Or: hackaday.io/project/190327-high-schoolers-build-a-radio-receiver Or: www.remmepark.com/circuit6040/SolderSmoke-DCR/SolderSmoke-DCR.html#AUDIO_AMP In this video, I just hoped to show what the receiver was capable of. To bad you found it so lacking in what you were looking for. Perhaps the links above, or maybe Google would help. Bill
Lots of information in the TH-cam video description.