In 1970 I entered an intensive Chemical Technologist program. Back then students were conversant within the metric and imperial system of measurements. Along with this was the imperative for all future Chemical Technologists to be able to conceive and design their own field measurement electronics. Computers were IBM 1130 s and 360, we used COBOL, Fortran IV etc. All of these computers and languages are now obsolete, but it left me with an intimate understanding of electronics, computer language rudiments, and a command of the theory of how and why things worked, how to upgrade and modify depending upon the research industry we would be working in. Additionally my father repaired tubed TVs and radios back in my youth, he had a portable tube tester that we took with us along with a bag of used tubes...:). What I appreciate about you is your command of the technology along with the "MacGiver" requirements of old. I sit by the hour and listen to each of your projects, so appreciative of your respect of your predecessors. I absolutely love the restoration of tube testing equipment and radios of all sorts. Your love of what you do, and the patience and dedication to excellence is very refreshing. When you align something, it is accurate and performs as designed! I wish I had continued into electronics as it was my first love. I may avail myself of some of your teaching courses, I am 68 now and would need a refresher for certain. Keep up the wonderful work, you have made this old guy happy to have found your channel. Blessings...Bill.
I get this rush when I get the notice a new video has been uploaded. I know I'm going to learn something and be very entertained for an hour. :-) Thanks, Paul.
I had never really paid much attention to nixie tubes per se, I was always fascinated by VFD displays and CRTs, until I was just watching Paul roll up and down the frequency whilst zoomed into the nixie tube display. I was delighted to notice how the numerals move from front to back within the tube as each number is illuminated, you can also see the structure of the numerals and the elements inside the tube itself. I now "get" the coolness of the venerable nixie tube. At 58 and still discovering new wonders almost every day in the wide, wide world of electronics.
This particular model of Westinghouse radio is by far the nicest looking antique radio I've ever seen. Of course this is my own opinion! The color of it is so rich that it just screams for attention. Sounds awesome as well.
Very interesting to see an old radio back into working order (with improvments). Brill to watch (for once) a bloke that totaly knows his stuff. Oh and the sound of the radio is beautiful, reminds me of my dads old radiogram (built around 1945/6). Just wonderfull.
Nice to see that old receiver. Reminds me of my young days experimenting with such a receiver, with exchangable tuning coils for different bands, plugged to octal sockets, had two large variable capacitors for tuning with 5" knobs with a window for indication (not ganged). Excellent durable parts. Long teak wood cabinet with top open on brass piano hinges...The antenna was more than 40 feet long running between two 15 feet high poles. Thank you very much.Regards
how did you obtain such gigantic amounts of information about electrical engineering? I first thought you where a lecturer, but you said that you worked at a reverse engineering company at some point in time, so are you just a genius?
Oh man Paul, that tip of using the scope probe for a sniffer,,,, I would have never thought of that but I am going to be using it from now on,,, so thank you for that and the circuit for the buffers and everything else. Just excellent as always.
What a gorgeous radio! I can see why you bought it. I've never been fortunate enough to find one that clean but I do love the old rigs no matter how much work they need. When you tuned to WWV at 5MHz it reminded me of being a kid back in the 70's and being fascinated by WWV. I think it may have been the impetus to get my Ham ticket albeit long after I was a kid. Thanks again for a great video. 73 NE5U Mike
I just love these older rigs and will have to start looking for one again and get back into tinkering with radios and older electronics. Its been I few years ago since I have messed with tubes, and I do kinda miss it...thanks for lessons. You are a good teacher...
I wish I had enough money to pay you whatever you ask for this jewel of a radio ! Of course you aren't going to sell it . Beautiful video on a more beautiful set . Keep them coming Mr Carlson !
my first time getting back into electronic since I was a teenager, I enrolled in a collage electronics class and my first class finals project I picked was building a headphone tube AMP. After watching all of your post I jumped so far ahead of the class in understanding radio, tube amp and lab scope diagnostics. I'm now a LAB scope want-to-be addict. Thank you
...your presentation style is very unique and the best I've ever seen. Personally I feel like I'm sitting next to you at your lab and looking over your shoulder :) Awesome work, thank you!
Wow, that's another great picture from your wife Mr. Carlson! This inspired the following thought. I know it probably won't be electronics related, but consider making a video showcasing some of your wife's work. Perhaps we can get some thumbs up to see who else would be interested or just say bugger all and go for it. Give it some thought. Cheers!
Lots of great info as always, thanks! I should probably be more fascinated at using the scope probe as an antenna, or the super simple but effective frequency-based voltage equalizer, or the super fast nixie tube counter, or that the AM broadcast band actually goes up to 1705 not 1605 like my car insists. Or that you picked up a station from California I think. But what fascinated me the most is soldering standoffs to things. :D I've never seen that before, it's pretty great. Your videos have been inspiring me to get back to work on my field coil speaker idea - I'm trying to make a software physics model to drive the field coil antiphase (mostly, accounting for the moving mass, etc) to the voice coil. I think it could make for super lightweight and high output loudspeakers. (I used to do pro sound reinforcement and those speakers aren't fun to carry around lol)
Thanks Paul, I'm trying to get a knight KG-625 going because of you. I also got one of those Hakko's because of you, entertainment at it's best. LSU! Go TIGERS!
Another great video! I always learn something here. I do however question the part where he grounds the oscilloscope to the chassis to sniff for the oscillator - it is always good practice to ensure the chassis isn't hot or otherwise above ground - a lot of older equipment had one leg of ac tied to the chassis, and with non-polarized plugs there is a 50-50 chance something is going to blow up.
Thank you so very much for sharing your knowledge. Wow! Scope as a sniffer. Very useful information. My troubleshooting skills have improved tremendously.
Howdy Paul,long time admirer of your work. I hunted down an Oscope on your advice back some years ago when I was building my 4 tube 4cx150 amp as a driver for my bigger 3cx5000 box. At the time cx150s could be bought for $20 a piece and Toshiba 2879s had just gone extinct 😂 I’ve been intrigued by the Nixie tubes for years and I have a few clocks,a call sign with my numbers and recently I came in to possession of a Heathkit Nixie tube frequency counter and that lit a fire under my arse to try to hunt down a way to get the frequency readout from my Yaesu VFO that’s modded in to my tram d201 tube base radio to display on a Nixie tube set top box. And if I can work it out or even pay someone to build it then i am going to do the same thing with my Browning golden eagle 3 piece tube base station. My idea was to pull the signal sample from a sampler connection via a bird sampler on the line section right off the s0239 right on the back of the radio. I figured if I can sent the signal to my test rack from the bird and the frequency is carried as well then I don’t see why it wouldn’t work but us nixies as the “meter” display. It would simply be displaying the freq from the vfo and not doing the work of a traditional counter. Or maybe I’m totally out of my mind 😂 I’d love to hear your thoughts on this if it makes any sense to you. But in my defense,I’m a Boilermaker not an electronic engineer,amp builder or anything else. I’m just a skip shooter who is a radio tinkerer.
I'm so impressed with your program. I drew electronic schematics for a High School Diploma. My class was a drafting student class and I would get a request for engineering drawings from the engineering department. We were going to the Moon then. I'm asking why is a transmission signal from so very distant solar system boundaries capable of being received,... having such a small wattage signal strength. I think this is a mere 20 watts. Why at all???? Thank you, John
Mr. Carlson, another Outstanding video! I have really enjoyed the series. Thank you for your time and expertise in this fascinating world of electronics. Hope you and your have a wonderful holiday season. Joel
It is amazing to me how popular AM radio still is in the States and Canada - here in Romania there are only 2 or 3 stations left and they're all part of the state-run network. There used to be some commercial radio on AM in smaller cities but i believe that is no longer the case, i think the last advertisement i saw printed on buses for a commercial AM radio station was at least 5 years ago.
Great video. I believe the chassis when made was fluxed and hot dipped in tin before components started being added. I have seen them being made. They are very easy to solder and speeds manufacture time.
This is really great, lots of tips. I can't wait to see the video on the RF amplifier. I wonder what it would take to add a VFO to that radio as well? I really need to build that counter. :)
Great video as always! I bought display module for a little transistor superheterodyne AM I built, but haven't been able to get it to read any frequency yet except from my signal generator. After a couple of failed attempts at making a buffer I gave up. The display has been in my junk box since. I think I'll dig it out and try your buffer. Let you know how it turns out later...
Love your Bak.Freq. is that tubes inside? That green eye is awesome. I am 53 and I have never heard am sound so good. Great job at building and explaining it. Great thanks to you for your time.
Paul says "electromagnetic speaker" when he means electro-dynamic speaker. He says "static" when he means noise. His choice of a 6688 tube is not very good since it consumes 0.3 amperes to light it. There are many pentodes that consume only 0.15 ampere at 6.3 volts. And since he added two 6688's, he is draining 0.6 amperes from the heater wiring which overloads the power transformer. If he had substituted silicon diodes for the vacuum tube rectifier he could have saved enough heater current to light the 6688"s, but as it is the power transformer is overloaded. -- W6HPH
@@fredbrown1017 I doubt Paul is overloading that massive transformer with 300 ma of additional filament current Fred. You don't know Paul very well from your comment do you Fred?
I dont know Jack about electronics, cant tell a diode from a transistor. But I'm learning a few things looking over the shoulder here. I find it fascinating.
By the way the "Dead Time" as you mention is commonly called "Backlash" in mechanical circles and those little split gears are Backlash eliminators or anti-lash gears as they load both leading and trailing sides of the gearset........they use them in pretty much any equipment that needs precision adjustments made......they can get as big as a picnic table in some industries.
Very nice project. I'm curious which version you left in the radio. I think it would be the tube buffer. It's more in keeping with the old radio. Any chance you will publish circuits like this on-line? I'd love to build some of these projects when I retire next year.
As with all your videos, I wish that I could like this twice Mr. Carlson. I hope one day to be as knowledgeable as you. A video on your background would be very interesting. I'd love to know how you gained all of your knowledge. I assume you've spent as much time learning on your own as well as in formal schooling. Are you in an electrical engineer? Thank you again for the videos you post.
Another option is to use paralleled sections of a 74HC04 inverter IC; this would give you high input impedance, and enough drive to push the signal through the coax cable, though if you go this route, I'd also include a 78L05 (TO92 pkg) in the power supply. You could even put this on the buffer board, too.
Hello and thank you for your videos. In this episode, you mention that there would be another one dedicated to the RF preamplifier that you included in this receiver. I would love to know about your design for the RF preamplifier, if there is already and episode about it (which I must have missed). Thank you for all the information that you are providing. Regards, Daniele
Awesome video, really enjoyed it, great level of detail. Really neat way to implement a period correct looking frequency counter. I'm especially looking forward to watching a video about your RF amp. I'm just getting ready to start building a parts-bin special tube radio from some of my stock, an all GT 9 tube PP mw/sw receiver. I will be using a 6sk7gt as an RF amp but it will be part of a tuned circuit using a 3 gang tuning capacitor and coupled with an RF stage coil after I finish rewinding one. Do you use a grounded grid / untuned design and how do you couple it to the radio? I have a couple of old 5 tube radios that tune into the high range of the SW band, 18-23MC and have contemplated fitting an RF amp as a kind of pre-selector to help with imaging problems in the higher end of the band, not too concerned with overall level of amplication as the radios work pretty well with my antenna set-up but as of yet haven't got off the starting line, your design might be just what im looking for.
Great Paul, Nice Tip on the Scope finding QSC.Yes your Video is worth missing a Good TV show at least get a hour of learning in on something new and worth while on my projects that I might have.So again Tks Paul 73's
Mr Carlson your old shortwave receiver is cool my hobbys are painting pictures and lisining to shortwave and ssb iam thinking about getting my ham license I have 4 shortwave receivers in June 5/2022 me and my cousin are going to a Swap meet in Milwaukee
Failed on my first attempt: Buffer as designed did not work with my low-power transmitter. Instead, I built a similar amplifier circuit capacitively coupled to the oscillator using 10p as you suggested which is outputting a 100mV sine wave. Oscillator remained stable, but the display module is still fluctuated wildly. Tested the module with my signal generator and it worked fine at 40mV. Also tested my buffered signal output with a RF meter and got a correct 97MHz reading same as the oscillator and antenna. Been doing some research... Do I need a Schmitt trigger or ADC to feed the analogue signal into the display module? No idea how to do that...
Just another quick question here before i go to sleep - have you got any experience with the use of the IRF510 mosfet in RF circuits? I have seen some HF and shortwave designs using this mosfet or multiples, but i am more interested in higher frequencies. I have stumbled upon a design done by a FM pirate claiming 23W @ 90MHz out of two IRF510s in parallel but i have never gotten it to work as a power amplifier, more like a power oscillator haha. I have the PDF if you would like to take a look at it.I did get a circuit using a single IRF510 to work as an amplifier at 95 MHz but the gain is low and it'll do something around the 10W level at 28 volts, there are much better devices that can still be easily acquired. I have acquired a decent selection of proper RF devices and i will go with those for the transmitters i build and test (on a dummy load, not an antenna, of course!), but that IRF510 circuit still stays on my mind. Because these mosfets are dirt cheap.Thank you.
Fascinating, and I am already working my changes on your set of designs. To keep the voltage down I am looking at Numitron instead of Nixie. However, Is there a way to apply this to a TRF radio? I was thinking at the final RF amplifier stage, or would you suggest at the Detector stage. My RF knowledge is not good enough to make assessment.
The diurnal effect on AM. Can you show us photos of the northern lights as a bonus, too? Is the antenna outside? Also, I love the flame figured mahogany(?) on the face. I can see why you bought it.
planguer caps that you are sniffing the signal with your oscilloscope? looks like they have a nut in the middle of its body. adjustable? are termal compensated in frecuency like "pipe cap" used in the generator of signal to compensate the drift in frecuency from temperature? good job as usual.
Hi Paul, This video is incredible. That rf tube amp really gave that radio some big ears. The Nixie tube display compliments the radio really well. Love watching the Magic Eye while you were tuning across the bands. :-) What antenna were you using with the receiver? WB3BJU
My scope loads down the RF preamp (preamp output/frequency counter input (PIC controller pin 3)) so that the frequency counter stops working. Mine is one of the “Wolf” based (Chinese) counters, where you you replace the “crummy” oscillator test ckt with a preamp mod, right on the board (per TheHWcave video). The counter with the preamp mod, works exactly as expected as shown in his video. I was just surprised that the scope loaded it so much. PS I used. 10x probe, AC coupled …
Hi Paul, I am building your solid state version of the buffer circuit to add a digital display to my Hammurlund HQ 129X using a through hole protoboard. Your schematic shows 12 components, however the picture of your populated board shows 13! Is there something missing on the schematic? Please advise. Thanks in advance! Bryan Woods W1KZF
Great video, thanks for sharing, I am little curious why you used a FET in front of an emitter follower? I would think that an emitter follower combined with your attenuation pad would have plenty of input impedance to not load down the oscillator. Keep up the great work!
Hi Michael. Using the bipolar transistor alone still causes oscillator loading (not much, but enough) The fet stage adds increased isolation, and the transistor provides drive for longer runs of coax into an appropriate termination.
Mr Carlson, my Oscilloscope is an old analog Gould advance , is there a way too add a digital or nixie tube frequency count to it? something like ezm electronics frequency counter DIY kit ?
Great video and fantastic piece of work. Just one minor question. The sine wave produced by the completed circuit (at about 33:50) does not look quite symmetrical ....is there a good reason for that?
In 1970 I entered an intensive Chemical Technologist program. Back then students were conversant within the metric and imperial system of measurements. Along with this was the imperative for all future Chemical Technologists to be able to conceive and design their own field measurement electronics. Computers were IBM 1130 s and 360, we used COBOL, Fortran IV etc. All of these computers and languages are now obsolete, but it left me with an intimate understanding of electronics, computer language rudiments, and a command of the theory of how and why things worked, how to upgrade and modify depending upon the research industry we would be working in. Additionally my father repaired tubed TVs and radios back in my youth, he had a portable tube tester that we took with us along with a bag of used tubes...:). What I appreciate about you is your command of the technology along with the "MacGiver" requirements of old. I sit by the hour and listen to each of your projects, so appreciative of your respect of your predecessors. I absolutely love the restoration of tube testing equipment and radios of all sorts. Your love of what you do, and the patience and dedication to excellence is very refreshing. When you align something, it is accurate and performs as designed! I wish I had continued into electronics as it was my first love. I may avail myself of some of your teaching courses, I am 68 now and would need a refresher for certain. Keep up the wonderful work, you have made this old guy happy to have found your channel. Blessings...Bill.
Hi Mr Carlson. I have come to love old electronics that I seen back in the younger years of my life. Good and enjoyable video
Thanks for your kind comment!
I get this rush when I get the notice a new video has been uploaded. I know I'm going to learn something and be very entertained for an hour. :-) Thanks, Paul.
AGREED
Me too, thanks Paul...!
Me three! :-)
I had never really paid much attention to nixie tubes per se, I was always fascinated by VFD displays and CRTs, until I was just watching Paul roll up and down the frequency whilst zoomed into the nixie tube display. I was delighted to notice how the numerals move from front to back within the tube as each number is illuminated, you can also see the structure of the numerals and the elements inside the tube itself. I now "get" the coolness of the venerable nixie tube. At 58 and still discovering new wonders almost every day in the wide, wide world of electronics.
This particular model of Westinghouse radio is by far the nicest looking antique radio I've ever seen. Of course this is my own opinion! The color of it is so rich that it just screams for attention. Sounds awesome as well.
Very interesting to see an old radio back into working order (with improvments). Brill to watch (for once) a bloke that totaly knows his stuff. Oh and the sound of the radio is beautiful, reminds me of my dads old radiogram (built around 1945/6). Just wonderfull.
Nice to see that old receiver. Reminds me of my young days experimenting with such a receiver, with exchangable tuning coils for different bands, plugged to octal sockets, had two large variable capacitors for tuning with 5" knobs with a window for indication (not ganged). Excellent durable parts. Long teak wood cabinet with top open on brass piano hinges...The antenna was more than 40 feet long running between two 15 feet high poles. Thank you very much.Regards
It's amazing how much knowledge Mr Carlson has. Thanks for sharing it.
Always glad to share Bruno :^)
how did you obtain such gigantic amounts of information about electrical engineering? I first thought you where a lecturer, but you said that you worked at a reverse engineering company at some point in time, so are you just a genius?
Ozzie Peck practice.
I like your Nixie Tube Frequency Counter Display as well. Old time look for old time radio, just perfect!
Thats a awesome looking and sounding radio
Oh man Paul, that tip of using the scope probe for a sniffer,,,, I would have never thought of that but I am going to be using it from now on,,, so thank you for that and the circuit for the buffers and everything else. Just excellent as always.
Thanks!
What a gorgeous radio! I can see why you bought it. I've never been fortunate enough to find one that clean but I do love the old rigs no matter how much work they need. When you tuned to WWV at 5MHz it reminded me of being a kid back in the 70's and being fascinated by WWV. I think it may have been the impetus to get my Ham ticket albeit long after I was a kid. Thanks again for a great video. 73 NE5U Mike
Glad you enjoyed Mike!
I just love these older rigs and will have to start looking for one again and get back into tinkering with radios and older electronics. Its been I few years ago since I have messed with tubes, and I do kinda miss it...thanks for lessons. You are a good teacher...
Thanks Vic!
They say: "1130 at the AM band", at the exact moment the digital dial shows 1130! That is SMOOOOOTH adjusting! Thanks for the video!
Amazing how well the frequency counter (first oscillator) tracks in that radio! Well done Paul! 73 Jim W7RY
Many thanks!
Love the vinyl cafe snippet when you’re tuning the radio. Brings me back to my childhood. Great videos, keep up the great work
I wish I had enough money to pay you whatever you ask for this jewel of a radio ! Of course you aren't going to sell it . Beautiful video on a more beautiful set . Keep them coming Mr Carlson !
Another fantastic video Paul. Circuit design and explanation was great. Thanks for the lesson.
Glad you enjoyed Buddy. Thanks for stopping by!
I really enjoy your channel, the amount of detail, and your willingness to share your abilities.
my first time getting back into electronic since I was a teenager, I enrolled in a collage electronics class and my first class finals project I picked was building a headphone tube AMP. After watching all of your post I jumped so far ahead of the class in understanding radio, tube amp and lab scope diagnostics. I'm now a LAB scope want-to-be addict. Thank you
Great, Your welcome!
You do amazing work, Paul. That's a gorgeous little Westinghouse receiver. The dial looks very "Stromberg Carlson-ish".
Thanks Jason!
Thank you for taking the time to scan through the frequency bands, there is certainly a lot to listen to in your area!
...your presentation style is very unique and the best I've ever seen. Personally I feel like I'm sitting next to you at your lab and looking over your shoulder :) Awesome work, thank you!
Wow, that's another great picture from your wife Mr. Carlson! This inspired the following thought. I know it probably won't be electronics related, but consider making a video showcasing some of your wife's work. Perhaps we can get some thumbs up to see who else would be interested or just say bugger all and go for it. Give it some thought. Cheers!
I am very sorry for my last post. I found that you have already designed an offset frequency counter. It is a very good design. CAL
No worries!
You make my day. Thank you for all the effort. I look for your new videos often.
Lots of great info as always, thanks! I should probably be more fascinated at using the scope probe as an antenna, or the super simple but effective frequency-based voltage equalizer, or the super fast nixie tube counter, or that the AM broadcast band actually goes up to 1705 not 1605 like my car insists. Or that you picked up a station from California I think. But what fascinated me the most is soldering standoffs to things. :D I've never seen that before, it's pretty great.
Your videos have been inspiring me to get back to work on my field coil speaker idea - I'm trying to make a software physics model to drive the field coil antiphase (mostly, accounting for the moving mass, etc) to the voice coil. I think it could make for super lightweight and high output loudspeakers. (I used to do pro sound reinforcement and those speakers aren't fun to carry around lol)
Another great video Mr. Carlson. Thanks.
jerry blood did you see the twist ending?
Thanks Paul, I'm trying to get a knight KG-625 going because of you. I also got one of those Hakko's because of you, entertainment at it's best. LSU! Go TIGERS!
It's so neet seeing a radio with the electric eye again !! Great video!!
Thanks Mr Frog.
Another great video! I always learn something here. I do however question the part where he grounds the oscilloscope to the chassis to sniff for the oscillator - it is always good practice to ensure the chassis isn't hot or otherwise above ground - a lot of older equipment had one leg of ac tied to the chassis, and with non-polarized plugs there is a 50-50 chance something is going to blow up.
Thank you so very much for sharing your knowledge. Wow! Scope as a sniffer. Very useful information. My troubleshooting skills have improved tremendously.
Glad you enjoyed!
Hi Paul, obviously you have had technical training. I would be interested in reading your autobiography if you decide to write it.
Regards Steve
WAT A KOOL SHORTWAVE RADIO RECIVER MR CAISON TEX ME ON MY CELL WHEN YOU HAVE TIME
Great as usual. If like this stuff, the Patreon for this channel is the best fantastic.
Howdy Paul,long time admirer of your work. I hunted down an Oscope on your advice back some years ago when I was building my 4 tube 4cx150 amp as a driver for my bigger 3cx5000 box. At the time cx150s could be bought for $20 a piece and Toshiba 2879s had just gone extinct 😂
I’ve been intrigued by the Nixie tubes for years and I have a few clocks,a call sign with my numbers and recently I came in to possession of a Heathkit Nixie tube frequency counter and that lit a fire under my arse to try to hunt down a way to get the frequency readout from my Yaesu VFO that’s modded in to my tram d201 tube base radio to display on a Nixie tube set top box. And if I can work it out or even pay someone to build it then i am going to do the same thing with my Browning golden eagle 3 piece tube base station. My idea was to pull the signal sample from a sampler connection via a bird sampler on the line section right off the s0239 right on the back of the radio. I figured if I can sent the signal to my test rack from the bird and the frequency is carried as well then I don’t see why it wouldn’t work but us nixies as the “meter” display. It would simply be displaying the freq from the vfo and not doing the work of a traditional counter. Or maybe I’m totally out of my mind 😂
I’d love to hear your thoughts on this if it makes any sense to you. But in my defense,I’m a Boilermaker not an electronic engineer,amp builder or anything else. I’m just a skip shooter who is a radio tinkerer.
Thanks Paul. That was a real treat! That is a pretty radio also.
Nice work Paul! That display is a great add on and that receiver looks and sounds great!
Thanks!
That is one good sounding radio! Thanks for showing the repair...
Thanks! Glad you enjoyed.
Thanks Paul, your videos are the best I have seen.
Thanks Ian!
I'm so impressed with your program. I drew electronic schematics for a High School Diploma. My class was a drafting student class and I would get a request for engineering drawings from the engineering department. We were going to the Moon then.
I'm asking why is a transmission signal from so very distant solar system boundaries capable of being received,... having such a small wattage signal strength. I think this is a mere 20 watts. Why at all????
Thank you, John
Mr. Carlson, another Outstanding video! I have really enjoyed the series. Thank you for your time and expertise in this fascinating world of electronics. Hope you and your have a wonderful holiday season. Joel
Nice capacitors smooth sound !
It is amazing to me how popular AM radio still is in the States and Canada - here in Romania there are only 2 or 3 stations left and they're all part of the state-run network.
There used to be some commercial radio on AM in smaller cities but i believe that is no longer the case, i think the last advertisement i saw printed on buses for a commercial AM radio station was at least 5 years ago.
Great video. I believe the chassis when made was fluxed and hot dipped in tin before components started being added. I have seen them being made. They are very easy to solder and speeds manufacture time.
For those people in the East side of the us with this type of vacuum tube radio like this, 103.1 FM in Chattanooga TN. it's a good radio station.
o Boy!! that incredible sound!! Just Terrific!
GREAT VIDEO as Always!! Thanks for the Osc Tip!
Glad you enjoyed!
This is really great, lots of tips. I can't wait to see the video on the RF amplifier. I wonder what it would take to add a VFO to that radio as well? I really need to build that counter. :)
Great video as always! I bought display module for a little transistor superheterodyne AM I built, but haven't been able to get it to read any frequency yet except from my signal generator. After a couple of failed attempts at making a buffer I gave up. The display has been in my junk box since. I think I'll dig it out and try your buffer. Let you know how it turns out later...
Love your Bak.Freq. is that tubes inside? That green eye is awesome. I am 53 and I have never heard am sound so good. Great job at building and explaining it. Great thanks to you for your time.
Love the vintage electronics...
You really know your stuff, thank you for this awesome video.....
Paul says "electromagnetic speaker" when he means electro-dynamic speaker. He says "static" when he means noise. His choice of a 6688 tube is not very good since it consumes 0.3 amperes to light it.
There are many pentodes that consume only 0.15 ampere at 6.3 volts. And since he added two 6688's, he is draining 0.6 amperes from the heater wiring which overloads the power transformer. If he had substituted silicon diodes for the vacuum tube rectifier he could have saved enough heater current to light the 6688"s, but as it is the power transformer is overloaded. -- W6HPH
@@fredbrown1017 I doubt Paul is overloading that massive transformer with 300 ma of additional filament current Fred.
You don't know Paul very well from your comment do you Fred?
Thanks for the info. I appreciate your tutorials very much.
I dont know Jack about electronics, cant tell a diode from a transistor.
But I'm learning a few things looking over the shoulder here.
I find it fascinating.
By the way the "Dead Time" as you mention is commonly called "Backlash" in mechanical circles and those little split gears are Backlash eliminators or anti-lash gears as they load both leading and trailing sides of the gearset........they use them in pretty much any equipment that needs precision adjustments made......they can get as big as a picnic table in some industries.
Very nice project. I'm curious which version you left in the radio. I think it would be the tube buffer. It's more in keeping with the old radio.
Any chance you will publish circuits like this on-line? I'd love to build some of these projects when I retire next year.
when I first saw the length of the video I said "not gonna happen" but here I am 1 hour later, thank you!!!
Glad you enjoyed!
As with all your videos, I wish that I could like this twice Mr. Carlson. I hope one day to be as knowledgeable as you. A video on your background would be very interesting. I'd love to know how you gained all of your knowledge. I assume you've spent as much time learning on your own as well as in formal schooling. Are you in an electrical engineer? Thank you again for the videos you post.
Thanks for your kind words Evan!
Nice job and love the sw receiver and counter unit. Copy the buffer circuit and thank you for that. Have a good one Carl 73`s
This is really a nice voice radio!
Another option is to use paralleled sections of a 74HC04 inverter IC; this would give you high input impedance, and enough drive to push the signal through the coax cable, though if you go this route, I'd also include a 78L05 (TO92 pkg) in the power supply. You could even put this on the buffer board, too.
...if you use a 74HC04 IC, you're not gonna get a sine wave output...(!)
Hello and thank you for your videos.
In this episode, you mention that there would be another one dedicated to the RF preamplifier that you included in this receiver.
I would love to know about your design for the RF preamplifier, if there is already and episode about it (which I must have missed).
Thank you for all the information that you are providing.
Regards,
Daniele
Awesome video, really enjoyed it, great level of detail. Really neat way to implement a period correct looking frequency counter. I'm especially looking forward to watching a video about your RF amp. I'm just getting ready to start building a parts-bin special tube radio from some of my stock, an all GT 9 tube PP mw/sw receiver. I will be using a 6sk7gt as an RF amp but it will be part of a tuned circuit using a 3 gang tuning capacitor and coupled with an RF stage coil after I finish rewinding one. Do you use a grounded grid / untuned design and how do you couple it to the radio? I have a couple of old 5 tube radios that tune into the high range of the SW band, 18-23MC and have contemplated fitting an RF amp as a kind of pre-selector to help with imaging problems in the higher end of the band, not too concerned with overall level of amplication as the radios work pretty well with my antenna set-up but as of yet haven't got off the starting line, your design might be just what im looking for.
Excellent, as always. Easy to appreciate. Thanks.
Glad you enjoyed!
really enjoy your teaching. what is your outside antenna setup, and how is it brought into the shop? thanks again
Beautiful receiver. Beautiful work.
Thanks Shain!
Awesome job Paul.
Thanks Ronnie!
Great Paul, Nice Tip on the Scope finding QSC.Yes your Video is worth missing a Good TV show at least get a hour of learning in on something new and worth while on my projects that I might have.So again Tks Paul 73's
Glad you enjoyed Dale!
I get the impression you do not like sports, neither do I. But your skills behind a tool are great.
Mr Carlson your old shortwave receiver is cool my hobbys are painting pictures and lisining to shortwave and ssb iam thinking about getting my ham license I have 4 shortwave receivers in June 5/2022 me and my cousin are going to a Swap meet in Milwaukee
Mr Carlson this cool Design and Build a Buffer circuit tube and Transistor
thanks i will build it keep making videos love them
Failed on my first attempt: Buffer as designed did not work with my low-power transmitter. Instead, I built a similar amplifier circuit capacitively coupled to the oscillator using 10p as you suggested which is outputting a 100mV sine wave. Oscillator remained stable, but the display module is still fluctuated wildly. Tested the module with my signal generator and it worked fine at 40mV. Also tested my buffered signal output with a RF meter and got a correct 97MHz reading same as the oscillator and antenna. Been doing some research... Do I need a Schmitt trigger or ADC to feed the analogue signal into the display module? No idea how to do that...
Great work Paul, I need to make a digital readout for my Kenwood com rec
Late comer to the video but really enjoyed it. Thank you.
*Excellent videos!* Such great knowledge and wonderful explanations. Thank you.
Thanks Robert!
Just another quick question here before i go to sleep - have you got any experience with the use of the IRF510 mosfet in RF circuits?
I have seen some HF and shortwave designs using this mosfet or multiples, but i am more interested in higher frequencies. I have stumbled upon a design done by a FM pirate claiming 23W @ 90MHz out of two IRF510s in parallel but i have never gotten it to work as a power amplifier, more like a power oscillator haha. I have the PDF if you would like to take a look at it.I did get a circuit using a single IRF510 to work as an amplifier at 95 MHz but the gain is low and it'll do something around the 10W level at 28 volts, there are much better devices that can still be easily acquired.
I have acquired a decent selection of proper RF devices and i will go with those for the transmitters i build and test (on a dummy load, not an antenna, of course!), but that IRF510 circuit still stays on my mind. Because these mosfets are dirt cheap.Thank you.
Fascinating, and I am already working my changes on your set of designs. To keep the voltage down I am looking at Numitron instead of Nixie. However, Is there a way to apply this to a TRF radio? I was thinking at the final RF amplifier stage, or would you suggest at the Detector stage. My RF knowledge is not good enough to make assessment.
Now to build a BFO circuit and your set! ~Jack, VEG
wow now that radio sounds a maze in
The diurnal effect on AM. Can you show us photos of the northern lights as a bonus, too? Is the antenna outside? Also, I love the flame figured mahogany(?) on the face. I can see why you bought it.
planguer caps that you are sniffing the signal with your oscilloscope? looks like they have a nut in the middle of its body. adjustable? are termal compensated in frecuency like "pipe cap" used in the generator of signal to compensate the drift in frecuency from temperature? good job as usual.
The way you describe the chassis being able to take solder very easily, it probably was tin plated by the manufacturer? It has that look to me.
What kind of antenna do you use for your radios? Something commercial, or one you built yourself?
Hi Paul,
This video is incredible. That rf tube amp really gave that radio some big ears. The Nixie tube display compliments the radio really well. Love watching the Magic Eye while you were tuning across the bands. :-)
What antenna were you using with the receiver? WB3BJU
My scope loads down the RF preamp (preamp output/frequency counter input (PIC controller pin 3)) so that the frequency counter stops working. Mine is one of the “Wolf” based (Chinese) counters, where you you replace the “crummy” oscillator test ckt with a preamp mod, right on the board (per TheHWcave video).
The counter with the preamp mod, works exactly as expected as shown in his video.
I was just surprised that the scope loaded it so much.
PS I used. 10x probe, AC coupled …
Thanks mr Carlson top video mate big thumbs up
Hi Paul,
I am building your solid state version of the buffer circuit to add a digital display to my Hammurlund HQ 129X using a through hole protoboard. Your schematic shows 12 components, however the picture of your populated board shows 13! Is there something missing on the schematic? Please advise.
Thanks in advance!
Bryan Woods W1KZF
Great video, thanks for sharing, I am little curious why you used a FET in front of an emitter follower? I would think that an emitter follower combined with your attenuation pad would have plenty of input impedance to not load down the oscillator. Keep up the great work!
Hi Michael. Using the bipolar transistor alone still causes oscillator loading (not much, but enough) The fet stage adds increased isolation, and the transistor provides drive for longer runs of coax into an appropriate termination.
Thumbs-up, Paul. Great stuff.
Faith and Football--must be Sunday. You're in BC?
Beautiful radio.
maybe add a translucent filter to your
digital display....the digits will be easier to see.
BTW - what do you use as an antenna for these radios?
Mr Carlson, my Oscilloscope is an old analog Gould advance , is there a way too add a digital or nixie tube frequency count to it? something like ezm electronics frequency counter DIY kit ?
Great video and fantastic piece of work. Just one minor question. The sine wave produced by the completed circuit (at about 33:50) does not look quite symmetrical ....is there a good reason for that?
Good one Paul...Thanks
Beautiful cabinet..
OSSUM TUBE BUFFER GREATE RADIO CAN'T WAIT FOR THE PRE AMP
Ah yes I love it!
Very interesting! However, it would have been good to see what the actual sensitivity of the receiver was.
Nice counter
Hey Mr Carlson: How come your not working for NASA???? Im sure your knowledge, expertise and experience will be highly suited.
Thanks for your kind comment!
MyMIXmedia exactly what I thought aswell.
And , that Tesla would be lucky to have Mr Carlson .
An all tube Tesla ! Lol.
You said "old receiver". The schematic says 1936-1937, but those coils look something from a crystal set. What do you think is going on there?