My first medium/shortwave was a Greymark kit. Four tube analog. All spaghetti wiring with Variable Air gap Tuner. Lost it in a flood. The kit Came with three plastic bobbins that had to be wound with copper magnet wire. Those plugged into sockets in the chassis. They had grooves molded into the plastic for # of turns and spacing. They need to be wrapped clean and tight. Ends soldered onto the pins. Tubes were about the diameter of a paper towel cardboard tube. You could wrap two sided adhesive tape carefully to replicate the plastic tube. Or chuck up 1-1/4 inch PVC pipe in a drill or lathe and carefully score grooves in the tubing.
Nice crafting! Don't forget to take it outside w/a battery radio sometimes..noise level goes down! Here is a great DIY variabale capacitor: 2 big tapered summer-drink tumblers. The inner has a metal foil (like sicky alu-foil insulation tape) on the outside, covered with the packing tape (insulated), the outer cup has the stickyfoil on the inside, tape-covered. You muckle on to overhang from each layer with an alligator clip. Nest the cups, press down a little, and rotate to tune!
Super cool, Tom! I just bought my first shortwave radio (a Tecsun Pl-310) and it is supposed to arrive in the mail tomorrow. I look forward to learning more from you! Much love from Ontario, Canada!
To all who may be wondering: this antenna is coupled to the radio inductively, which means there is no physical contact between the radio and the antenna. The radio is simply put in close proximity to the antenna, and the antenna is tuned (by means of the capacitor) for peak signal. I cannot tell you exactly how to connect a capacitor to the ends of the looped wire, as capacitors vary. Some experimentation is called for. For the capacitor I used, one end of the wire loop is connected to one of the terminals on the capacitor, and the other end of the loop is attached to the chassis.
👍👍👍👍👍Thanks for clarifying. Total newbie but eager to learn. That I beleive is the 'chassis' of the capacitor. How about powering the antenna? Separate power or generated from magnetic coil when RF signal brushes against it? Thanks again, I am so much nearer to building my own loop antenna.
Now that's magic! Very well done and should be crystal clear in your tree house. Just getting started with radio's and struggling to get to grips with antennas, it seems like a dark art, I will be trying your project once I get some supplies. Thanks for sharing, great channel!
I'm always surprised at how many people claim that a loop antenna such as the Tecsun AN-200 has no effect on reception. It's clear to me that they are not doing it right. The right radio is important, as is positioning of the antenna relative to the radio and dialing in the frequency correctly on the antenna. I've always had excellent results with the AN-200.
Thank you for this video. You seem to be quite knowledgeable about this subject, so I'm seeking some advice. I have recently restored a 100 yr. old Atwater-Kent AM Model 55 radio. Very little work was performed on the electronics unit itself, as you could imagine after 100 years some of the antique wire was 'petrified'. It has vacuum tubes, they were all tested, 2 needed to be replaced and were. Upon energizing the radio, all the tubes have a nice glow. But I seem to be having an antenna issue. While I can hear some static through the speaker, I'm not picking up any stations. I thought it was worth trying one of those cheapo loop antennas with 2 wires. The radio itself has 3 spring loaded antenna connections, a ground, a short local connection, and one for long distance stations. While trying the loop antenna, I heard a voice near the bottom of the band for about 2 or 3 seconds, but not after that. There is still some static through the rest of the band. If capacitance coupling is necessary, I'm not sure how that is achieved. The front panel of the radio does have a selector that chooses between the long and short antenna capabilities. Could you offer a suggestion regarding the antenna hook-up arrangement?
I made mine today and working surprisinly well! I used a laptox box too, had enameled wire I had as surplus and a varicap from a old radio once disabled and saved. Then with some hot glue as aid did the turns. Many tnx for your practical advises and keep on!
This is awesome, I could really use this. I’m having trouble finding the adjustable capacitor, would be great to have those instructions for a diy option. We’re you able to post those instructions too?
Saddly, you placed the Channel Master in front of your antenna/variable capacitor combo, can't see how it's all connected. Is the loop antenna connected to the radio? How did you connect the capacitor, with both leads or just one? Please reply
@@ayebee1207 Total Newbie here, was also wandering how those connect together. Thanks for pointing out. One more piece to figure out... how to connect capacitor to loop antenna... Thanks again.
Best I can tell you used bare non- jacketed wire? Can you wrap regular light gauge jacketed wire as I do not have bare wire? Thanks for your very good video👍
This isn't on topic but have you seen the plans for the Carver ultimate AM antenna? It's for radios that have terminal connections. Basically it's four turns of wire on a 12" square form. I used a large coffee can for a form and doubled the #turns to compensate for the six inch coffee container size. I did experiment a bit to find the best #turns for the different size. I use it for my stereo receiver that requires a loop antenna for am. It works remarkably better than the cheap little loop included with the receiver.
Great video!!! Just watched this and the performance of this homebrew is very impressive. I'm building one right now but the only variable capacitor I could find is a dual gang unit from an antique Silvertone radio. How critical is the value and type of tuning capacitor for this project? I don't want to rip the old radio apart if the tuning capacitor won't be appropriate. Thanks!
Does the homemade loop antenna have to be hooked up to the tube radio's internal loop antenna on the back of the compressed wood panel or or does it just stand alone. I happen to have that tuner capacitor and a bunch of other parts including 500 tubes I got from the swapmeet. Hopefully I can get better reception. A million thanks "Radiodog."
Very interesting but you did not show how you hooked the wires between the capacitors and the radio. does the radio have two screw terminals on the back? is everything hooked in series?
Since Radio Shack closed, you have nowhere to go for electronics stuff, except eBoo or Amazool. You can easily get antennas for ham radio, but there is nothing for shortwave. The capacitor is only available from a specialty vendor and are VERY expensive, unless you can make one yourself.
It works by induction....no connection to the radio. I made one with a 16 inch pizza box, 16 turns of 24 AWG magnet wire, and a 450 pf tuning capacitor. See a demo on my channel.
Would those AM-FM radios from the 80s that are sold in Goodwill and such make for a good capicator for this project???? Ours has a ton of them for a $1
@Radiodog I know this video is 3 years old, but I just found it. I have an old Technics SA 110 adio receiver. It came with an AM loop antenna, but that was lost. There was no variable capacitor on the antenna, it just plugged into an RCA jack. With your desugn, can I skip the capacitor and put some twists in the lead wires to a 6:24 n RCA plug?
You don't even need a square box. I've seen them make from round boxes, rectangular ones, wood forms, etc. The only problem with these simple loop antennas is that they are only useful for the AM broadcast band (520 - 1720 kHz) so you need something complicated and expensive for the rest of the shortwave bands.
Two questions: does the box have to be one square of 12 inches per side and 4 inches deep and do the wires have to be equally spaced? This is a pretty cool video. Thanks.
I purposefully made the dimensions approximate. 12" square, or thereabouts. I suppose it could be a bit rectangular, although that might affect its performance. I did my best to make the wires equally spaced. Here's a link to a calculator online, if you want to actually measure. (I was attempting this one with rough measurements.): earmark.net/gesr/loop/joe_carr_calc.htm
Radiodog, Greetings! ---- Living in eastern KY, AM radio signals are very weak to non-existent to stations only 1-hr away. I followed your directions on the DIY Loop Antenna using 100-ft of doorbell wire and went out and bought a variable tuning capacitor similar to the one you show in your video --- mine was rated as a single 365 pF. Being a neophyte in the amateur radio world, should I attach both ends of the loop ant. to the opposite leads of the capacitor (mine has 4 contact leads)? I'm not getting any results close to what you had in your video. Any advice you can provide would be greatly appreciated. Thanks!
I have a bust but stereo the antennas are cheap. I’m from Chicago and I’m picking up broadcasting from Nashville @ night, but the volume goes up and down. Is their any way without getting outdoor antennas to fix that problem?
Ok, you made a box antenna and you connect it to a capacitor (you don't say why ???). You don't show how everything is connected ... how are we supposed to connect everything? Can this be used for a car radio ?
The "box" antenna isn't connected to the radio - it is placed close to it so it can "couple" to the ferrite rod antenna inside the radio. Experiment for yourself, there are lots of different variable capacitors. On the older types clip a lead to the metal frame and another lead to one of the tabs attached to the moving vanes. The wire loops form an inductor which with the variable capacitor make a "tuned" circuit. That is basically how radios work. I don't suggest you try balancing one of these on your car's dashboard whilst turning the capacitor control and driving!
It`s probably a good bit better but the Tecsun works really well. There isn`t a lot of difference until you use much larger loops from what I`ve seen. This one looks twice as big so it likely has more gain but not a whole lot more from the videos I`ve seen on UA-cam.
Can anyone tell me why my Anker 15600 mAh USB battery charger/battery pack is shutting down when attempting to power my MLA-30 Active Loop Antenna??? Is there a simple cure to this dilemma? Thanks
You do not show us, how you hooked the wire to the capacitor, and then the capacitor to the radio. You only show the front of the radio. I already know what the front of a radio looks like.
Hello sir. I just bought this 365 pf variable capacitor from the link you've provided in this video (mtmscientific.com). I am from Philippines. Im just worried a little bit because i emailed them but till now no response still. Is this a legit online store? I hope it is not a fake store. Because i already paid it through paypal. Im worried a little bit.
Why? Would you want to disassemble an old radio? Radios of all types are becoming rare. Maybe FIX the old radio. Buy your new electronic parts from ebay/amazon, Digikey, Mouser. I have accumulated many old electronics. And wasted many hours trying to desolder components. And destroying parts by getting them too hot in removal. Goodwill stores get a huge amount of electronics. Talk to the guys outback in receiving for special things.
My first medium/shortwave was a Greymark kit. Four tube analog. All spaghetti wiring with Variable Air gap Tuner. Lost it in a flood. The kit
Came with three plastic bobbins that had to be wound with copper magnet wire. Those plugged into sockets in the chassis.
They had grooves molded into the plastic for # of turns and spacing.
They need to be wrapped clean and tight.
Ends soldered onto the pins.
Tubes were about the diameter of a paper towel cardboard tube. You could wrap two sided adhesive tape carefully to replicate the plastic tube. Or chuck up 1-1/4 inch PVC pipe in a drill or lathe and carefully score grooves in the tubing.
Nice crafting! Don't forget to take it outside w/a battery radio sometimes..noise level goes down!
Here is a great DIY variabale capacitor: 2 big tapered summer-drink tumblers. The inner has a metal foil (like sicky alu-foil insulation tape) on the outside, covered with the packing tape (insulated), the outer cup has the stickyfoil on the inside, tape-covered. You muckle on to overhang from each layer with an alligator clip. Nest the cups, press down a little, and rotate to tune!
Super cool, Tom! I just bought my first shortwave radio (a Tecsun Pl-310) and it is supposed to arrive in the mail tomorrow. I look forward to learning more from you! Much love from Ontario, Canada!
Do u like your tecsun?
It's a pity you don't show one of the most important part, as least for a newbie : how to attach the wire the capacitor ? Have a nice day Tom
To all who may be wondering: this antenna is coupled to the radio inductively, which means there is no physical contact between the radio and the antenna. The radio is simply put in close proximity to the antenna, and the antenna is tuned (by means of the capacitor) for peak signal.
I cannot tell you exactly how to connect a capacitor to the ends of the looped wire, as capacitors vary. Some experimentation is called for. For the capacitor I used, one end of the wire loop is connected to one of the terminals on the capacitor, and the other end of the loop is attached to the chassis.
WHAT "chassis"??? Please expound, thanks!
👍👍👍👍👍Thanks for clarifying. Total newbie but eager to learn.
That I beleive is the 'chassis' of the capacitor.
How about powering the antenna? Separate power or generated from magnetic coil when RF signal brushes against it?
Thanks again, I am so much nearer to building my own loop antenna.
Does the capacitor help with the fact that the wire isn't the exact 1/2 wave length or something?
@@usernamemykelthe capacitor frame is the "chassis".
Now that's magic! Very well done and should be crystal clear in your tree house. Just getting started with radio's and struggling to get to grips with antennas, it seems like a dark art, I will be trying your project once I get some supplies. Thanks for sharing, great channel!
Very dark art. And RADIO WAVE TYPE MATTER. FM antenna - much easier and for me more important.
I'm always surprised at how many people claim that a loop antenna such as the Tecsun AN-200 has no effect on reception. It's clear to me that they are not doing it right. The right radio is important, as is positioning of the antenna relative to the radio and dialing in the frequency correctly on the antenna. I've always had excellent results with the AN-200.
Thank you for this video. You seem to be quite knowledgeable about this subject, so I'm seeking some advice. I have recently restored a 100 yr. old Atwater-Kent AM Model 55 radio. Very little work was performed on the electronics unit itself, as you could imagine after 100 years some of the antique wire was 'petrified'. It has vacuum tubes, they were all tested, 2 needed to be replaced and were. Upon energizing the radio, all the tubes have a nice glow. But I seem to be having an antenna issue. While I can hear some static through the speaker, I'm not picking up any stations. I thought it was worth trying one of those cheapo loop antennas with 2 wires. The radio itself has 3 spring loaded antenna connections, a ground, a short local connection, and one for long distance stations. While trying the loop antenna, I heard a voice near the bottom of the band for about 2 or 3 seconds, but not after that. There is still some static through the rest of the band. If capacitance coupling is necessary, I'm not sure how that is achieved. The front panel of the radio does have a selector that chooses between the long and short antenna capabilities. Could you offer a suggestion regarding the antenna hook-up arrangement?
I made mine today and working surprisinly well! I used a laptox box too, had enameled wire I had as surplus and a varicap from a old radio once disabled and saved. Then with some hot glue as aid did the turns. Many tnx for your practical advises and keep on!
Really nice, Tom! Meet to see you again!
Hot glue a bottle cap to the shaft of the capacitor so your hand touching it doesn`t interfere with tuning.
Good tip for me to try.
“Redneck Tech Tips”
would solid copper telephone wire suffice ? I got a spool of the blue/ yellow telco wire handy
This is awesome, I could really use this. I’m having trouble finding the adjustable capacitor, would be great to have those instructions for a diy option. We’re you able to post those instructions too?
It seems like you could make it into a regenerative amplifier pretty easily with a battery and a FET like an MPF102 and a tickler loop.
For anyone who is often working on electronics you can actually get this wire (magnet wire) from things like small transformers on circuit boards:)
Did you ever make that "next" video about building an antenna from regular materials? You kinda lost me at "capacitor" : )
Enjoying your videos. Good to see you doing them again.
Saddly, you placed the Channel Master in front of your antenna/variable capacitor combo, can't see how it's all connected. Is the loop antenna connected to the radio? How did you connect the capacitor, with both leads or just one? Please reply
Max Warfield. It is an inductor RF device.
No physical connection with the radio.
@@ayebee1207 Total Newbie here, was also wandering how those connect together.
Thanks for pointing out.
One more piece to figure out... how to connect capacitor to loop antenna...
Thanks again.
how did you connect the capacitor to the radio?
lookin forward to watchin you build a capacitor. Love this channel!
Best I can tell you used bare non- jacketed wire? Can you wrap regular light gauge jacketed wire as I do not have bare wire? Thanks for your very good video👍
His wire is enameled(spelling?) so not really bare.
Yes you can use plastic coated wire also.
This isn't on topic but have you seen the plans for the Carver ultimate AM antenna? It's for radios that have terminal connections. Basically it's four turns of wire on a 12" square form. I used a large coffee can for a form and doubled the #turns to compensate for the six inch coffee container size. I did experiment a bit to find the best #turns for the different size. I use it for my stereo receiver that requires a loop antenna for am. It works remarkably better than the cheap little loop included with the receiver.
Wonderful vid! I'm a rank beginner and I loved it. Although I wish I could make a variable capacitor appear out of thin air!
ua-cam.com/video/UHft0la2Xl4/v-deo.html you can with some tinfoil and tape and some other items around the house
Great Scotts! Radiodog. Great Video. I will give it a try.
If you wrap the wire around the radio it works even better.
Good stuff Tom, keep these great videos coming, many thanks.
Great video!!! Just watched this and the performance of this homebrew is very impressive. I'm building one right now but the only variable capacitor I could find is a dual gang unit from an antique Silvertone radio. How critical is the value and type of tuning capacitor for this project? I don't want to rip the old radio apart if the tuning capacitor won't be appropriate. Thanks!
Hi, I'm new to radio and I am trying to build my antenna. However, I don't have a capacitor. Will it work with out it?
Does the homemade loop antenna have to be hooked up to the tube radio's internal loop antenna on the back of the compressed wood panel or or does it just stand alone. I happen to have that tuner capacitor and a bunch of other parts including 500 tubes I got from the swapmeet. Hopefully I can get better reception. A million thanks "Radiodog."
Very interesting but you did not show how you hooked the wires between the capacitors and the radio. does the radio have two screw terminals on the back? is everything hooked in series?
Since Radio Shack closed, you have nowhere to go for electronics stuff, except eBoo or Amazool. You can easily get antennas for ham radio, but there is nothing for shortwave. The capacitor is only available from a specialty vendor and are VERY expensive, unless you can make one yourself.
Same question everyone else is asking. How did you connect the wires to the radio?
It works by induction....no connection to the radio. I made one with a 16 inch pizza box, 16 turns of 24 AWG magnet wire, and a 450 pf tuning capacitor. See a demo on my channel.
There's no a physical connection, just put it close to your radio receiver and radio waves do the rest. It's a resonator!
Would those AM-FM radios from the 80s that are sold in Goodwill and such make for a good capicator for this project???? Ours has a ton of them for a $1
Twaskyou sr Blessings this is my hobby for many years to get lot fairs stations radio and tv.
I like the Channel Master radio, but I wonder if your loop will cover the extended part of the AM band.
Do you have a video that shows where on the tuning capacitor you connect the antenna wires?
Thanks for nice easy project :) can this type antenna good for short wave as well?
@Radiodog I know this video is 3 years old, but I just found it. I have an old Technics SA 110 adio receiver. It came with an AM loop antenna, but that was lost. There was no variable capacitor on the antenna, it just plugged into an RCA jack. With your desugn, can I skip the capacitor and put some twists in the lead wires to a 6:24 n RCA plug?
You don't even need a square box. I've seen them make from round boxes, rectangular ones, wood forms, etc.
The only problem with these simple loop antennas is that they are only useful for the AM broadcast band (520 - 1720 kHz) so you need something complicated and expensive for the rest of the shortwave bands.
Another idea for a video...
Make a high Q loop antenna with pegs in a board alternating the windings above or below each peg.
Two questions: does the box have to be one square of 12 inches per side and 4 inches deep and do the wires have to be equally spaced? This is a pretty cool video. Thanks.
I purposefully made the dimensions approximate. 12" square, or thereabouts. I suppose it could be a bit rectangular, although that might affect its performance. I did my best to make the wires equally spaced.
Here's a link to a calculator online, if you want to actually measure. (I was attempting this one with rough measurements.): earmark.net/gesr/loop/joe_carr_calc.htm
Can magnet wire be used for this project? I have over 100 ft of it
Tom just making sure I understand, the other end of the loop is attached to the chassis of the capacitor, correct?
This was an awesome video
You need to get the capacitor as surplus as they are very expensive.
Yes, you can also make a home made on for doing an experiment. It is not as nice as a professionally made one but it can be good enough.
Radiodog, Greetings! ---- Living in eastern KY, AM radio signals are very weak to non-existent to stations only 1-hr away. I followed your directions on the DIY Loop Antenna using 100-ft of doorbell wire and went out and bought a variable tuning capacitor similar to the one you show in your video --- mine was rated as a single 365 pF. Being a neophyte in the amateur radio world, should I attach both ends of the loop ant. to the opposite leads of the capacitor (mine has 4 contact leads)? I'm not getting any results close to what you had in your video. Any advice you can provide would be greatly appreciated. Thanks!
Very good!
Thank u.
💚💛💙🇧🇷🇧🇷🇧🇷
I have a bust but stereo the antennas are cheap. I’m from Chicago and I’m picking up broadcasting from Nashville @ night, but the volume goes up and down. Is their any way without getting outdoor antennas to fix that problem?
Ok, you made a box antenna and you connect it to a capacitor (you don't say why ???). You don't show how everything is connected ... how are we supposed to connect everything? Can this be used for a car radio ?
The "box" antenna isn't connected to the radio - it is placed close to it so it can "couple" to the ferrite rod antenna inside the radio. Experiment for yourself, there are lots of different variable capacitors. On the older types clip a lead to the metal frame and another lead to one of the tabs attached to the moving vanes. The wire loops form an inductor which with the variable capacitor make a "tuned" circuit. That is basically how radios work. I don't suggest you try balancing one of these on your car's dashboard whilst turning the capacitor control and driving!
3:55 Uh huh yer not sa good with your math either are ya. Nevertheless, I'm enjoyin yer videos and learning a LOT!
How does your home made box antenna compare to the tecsun loop antenna I see on your desk.?
It`s probably a good bit better but the Tecsun works really well. There isn`t a lot of difference until you use much larger loops from what I`ve seen. This one looks twice as big so it likely has more gain but not a whole lot more from the videos I`ve seen on UA-cam.
Hmmm...good question. I just built this as I made the video, so I haven't really tested yet. I'm guessing more or less the same.
@@tomjones239 Thanks
How to connect wire with am radio and please tell me number of capacitor picture and size
Tnx for the vid.really interesting.
Can anyone tell me why my Anker 15600 mAh USB battery charger/battery pack is shutting down when attempting to power my MLA-30 Active Loop Antenna??? Is there a simple cure to this dilemma? Thanks
Could you please put a copy of a schematic?
I heard Curtis on 77 WABC
Very cool!
Excellent
Gracias amigo
Love It!
1:29 okay buddy ya lost me there. I thought you said there wasn't gone be a lot of math!
Will this work on a regular radio. I’m tired of not being able to listen to the ball game and want a decent channel
what material is the wire made of?
Copper.
Or something plastic or non metal to pervent interference
Excelente!!
Super sir
You do not show us, how you hooked the wire to the capacitor, and then the capacitor to the radio. You only show the front of the radio. I already know what the front of a radio looks like.
Yes...I could've done this SO much better. Sorry about that.
@@Radiodog So why don't you type in the answer?
@@ababner317 I agree, without that answer the video is void.
@@Radiodog duh !
So many words to say so little. Maybe a quick sketch of the circuit? This video could have been much better with a bit of planning.
Hello sir. I just bought this 365 pf variable capacitor from the link you've provided in this video (mtmscientific.com).
I am from Philippines. Im just worried a little bit because i emailed them but till now no response still.
Is this a legit online store? I hope it is not a fake store. Because i already paid it through paypal. Im worried a little bit.
👍👍👍
👍
like
Why? Would you want to disassemble an old radio? Radios of all types are becoming rare. Maybe FIX the old radio. Buy your new electronic parts from ebay/amazon, Digikey, Mouser.
I have accumulated many old electronics.
And wasted many hours trying to desolder components. And destroying parts by getting them too hot in removal.
Goodwill stores get a huge amount of electronics. Talk to the guys outback in receiving for special things.
waste of time, you did not give enough imfo how did you couple it to the rec. wire or just sitting there,