How to Make Crystal Radio Amplifier for Speaker
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- Опубликовано: 31 июл 2013
- How to make an amplifier for a crystal radio that plays it on a loud speaker, like a permanent magnet speaker. This shows the circuit then goes step-by-step through making it on a perfboard. This amplifier circuit is built around the LM386 amplifier chip,
and uses various capacitors and resistors. I used an equivalent part for the LM386, the NTE823.
This video has correct English captions. Click on the CC button at the bottom of the video to see them.
The book I mentioned that I first found this project in (very good
collection of projects):
"Radio Receiver Projects You Can Build" by Homer L. Davidson
The LM386 chip document I mentioned containing the circuit and more
chip details on Texa Instruments' website:
www.ti.com/lit/ds/symlink/lm38...
See also:
How to Make/Build a Crystal Radio
• How to Make/Build a Cr...
Portable Crystal Radio using Loop Antenna and Pizza Box
• Portable Crystal Radio...
How Radiation Works - Americium 241, Alpha Particles and Gamma Rays
• How Radiation Works us...
How a Crystal Radio Works
• How a Crystal Radio Works
How to Make Amplifier for Crystal Radio Earpiece
• How to Make Amplifier ...
For my webpage about making this crystal radio amplifier, go to:
rimstar.org/science_electronic...
Follow behind-the-scenes on:
Twitter #!/RimStarz
Google+ plus.google.com/1163951251362...
rimstar.org
Music used from 0:15 to 2:31 and from 9:08 to 9:35:
5 Cents Back - music by audionautix.com
Music used from 2:37 to 4:50 and 7:44 to 8:25:
Sneaky Snitch Kevin MacLeod (incompetech.com)
Licensed under Creative Commons: By Attribution 3.0
creativecommons.org/licenses/b...
ISRC: USUAN1100772
Music used from 4:50 to 7:44:
Decisions Kevin MacLeod (incompetech.com)
Licensed under Creative Commons: By Attribution 3.0
creativecommons.org/licenses/b...
ISRC: USUAN1100756 
Наука
At last a parts list . I cannot believe that people make really videos on electronics , but don't either talk you through the parts and actually show you the parts (as in this video )required or actually write down a parts list Excellent ten out of ten
I've known about this channel for years, but only recently started delving into these videos. I feel dumb for putting it off so long. This is precisely the kind of content I've craved!
Made one as a scouting project when I was 12. It worked really well even on camping trips. Used earphones and it worked very well. In 1966 it was cool. Simpler times.
I love all of your videos! Thanks for establishing an atmosphere of curiosity. I plan to make the crystal radio or maybe a similar foxhole radio and the amplifier makes a nice and practical addition! Keep up the good work!
Ik this is a bit too late to ask but did you make it?
Sad it was 10 years ago but wow, I finally found what it looks like in a schematic showing the components as they are put together it just makes it easier to understand. Now I can read a schematic Just this is so much better.
Haven't tried the amp yet. But I did build the radio staying pretty much to your design. I used a piezo buzzer for an earpiece, and tried and tried. I even rewound the coil with taps. I was finally in business when a 47K resistor was placed between the earpiece leads. This was great fun. Thanks RimstarMan.
steve happe Glad to hear you got it working! Sounds like you didn't have enough leakage in the reverse direction through your diode, but with the resistor it now takes that path. Thanks for letting me know.
My pleasure. Thanks for watching them.
Thanks. I'm glad you liked it. Thanks for watching it all!
Thanks for pointing it out. I'll try it both ways and then add an annotation to the video. Much appreciated.
Hi
This morning I tried out my crystal radio with an amplifier based on your video. Worked really well! I have a hearing loss and the crystal radio, without the amplifier, did work but at a volume level that made the received signal difficult to understand. Thanks!
Great! It's always wonderful to hear about the ones that worked, so thanks!
Loved watching this. Thank you
Nice job, good clear instructions and very helpful.
Thanks. I just watched your video about yours. They're very similar. I love your use of a cardboard box for mounting the circuit.
Thats so cool. And it sounds really clear too, nice job!
I'm with you on that. The more homemade, the more satisfying.
I love your jar! The project boxes they sell are sooooo expensive!
By popular demand I made an amplifier for a crystal radio... and put it in a peanut butter jar with the speaker in the lid on top. Step-by-step details for making it included.
ii
Hi
Thanks
thank you MR for your valuable videos
You're welcome. Glad you liked it.
Very cool.... I can't wait to get started.
Great video!
wonderful..i was looking for it!
been thinking about doing that whole setup, but have the amplifier be powered by a stirling generator and have a diy speaker instead of a repurposed one.
when I do the project, i'll be following a lot of your work.
so thank you for the inspiration
U make it all look so easy!!
😁
I was at a sort of Maker Faire tonight and saw a new approach which was to buy a sort of copper tape from craft stores which is actually a good conductor and use that tape to make the traces. It was solderable so you solder where two pieces meet and of course where they meet the components. They'd made a mini power supply this way.
i made this amp and i connect a jack (not a cristal radio) and it works!!!!:))
Cool! Glad to hear it!
Great info thanks
Cool it good. :) Thanks!
here is very simple amp for cristal radio works greath I use old cellphone headphones ( I use only one of them) and volume is greath I can understand everything .. I was amazed how good it works beacouse its so simple and so
good .
I think it's a well made movie. great explained
Gracias. Me alegro de haber podido ayudar! (Google translation)
I saw and heard a radio powered crystal set in the early 1950's. Invented by Wes Nichols. It detected a strong local station and used the dc to power a Germanium transistor crystal set. A 12" speaker no less!
Very well explained, thanks for sharing. Maybe some additional subtitles would be a help for we non anglophones.
this is so cool :D
Around 40 years ago I had a Radio Shack 50 in 1 project kit that had a crystal radio in the mix. I had about a 25 meter antenna out my bedroom window tied high in a tree and a copper rod driven into the ground for my ground. I recall making a small modification to the circuit that allowed me to pick up short wave, if I recall it had to do with where I tapped into the coil which was of the ferrite variety. It seemed that the short wave stuff was below the low end of the AM dial. I took the output into a two transistor amplifier project in the same kit and then ran the output from the amplifier to a low ohm speaker, I seem to recall it was a 4 ohm. You could run it off the 1.5 volt solar panel in the kit or of an AA battery. I listened to that radio for hours, all kinds of stuff from Europe. It really only worked well at night, and was much better in the winter than the summer. You could also pick up the Greenwich mean time beacon. Your project brought back some memories and I was wondering what modifications it would take to pick up the short wave AM signals. I'm pretty sure the amplifier would be mandatory, as would the really long antenna.
jgh59nerdshack That sounds like a great kit you had! Regarding modifications for shortwave, I haven't tried it myself. However, I have a kit that uses jumpers to adjust the circuit for shortwave and they do so to add an extra 470pF capacitor in series with the tuning capacitor, which would shrink the tuning range making it easier to tune in.
Thanks. What would the sd card be for? I guess the usb is for power?
Nice, now I have a base for my own cassette player
Hi! I made something like this using two npn transistors. I've also added some inductors and capacitors to filter audio signal. I have much better sound quality with this method. I'm using passive filter, but you can make one powered from battery.
Are you saying you connected the 10k potentiometer differently? What you described is the same as mine. Did you put the 10uF electrolytic capacitor in between pin 3 and the potentiometer? The potentiometer has three places to connect to. It is important that you connect to the right ones. Does your crystal radio work without the amplifier? Are you sure the electrolytic capacitors are connected the right way? The electrolytic capacitors have a positive and a negative.
Thanks.
Super sir.
Well no progress has been made yet. I've been messing around with making a cheap SDR radio with the Ham It Up v1.0 - RF Upconverter and the RTL2832U & R820T Tuner dongle. Really cool set up and a cheap SDR radio for under $70. I love shortwave!
Oh, neat. A multi-speaker setup makes sense. One speaker would be pushing air while the other is pulling. Cool. I'll have to look at the output on my oscilloscope to see the single speaker case better.
It does seem that way. When people ask questions, I often have one or more videos with the answers. :)
Thumbs up before watching
Does your crystal radio work when you listen using a crystal earpiece? Maybe you are not tuning into any radio stations because there is a problem with the crystal radio. Do you have a good ground? Do you have a good antenna? Is your battery charged?
I want to try using bare transistors too. Thought I'd try the chip this time, though. I think the amplifier was amplifying what was a noisey signal from the crystal radio. A french station was coming in crystal clear and came out of the amp crystal clear and much louder but since it was french and most people watching this video at least know english, I went with the noisier english station. Maybe I shouldn't have. How long is your antenna?
nice bro
I don't know how you'd make one that small. Do they make high enough capacitance variable capacitors and inductors that size? Can they be made? I guess that's the limiting factor. There might also be a component spacing issue.
We made one at work that did not require an amplifier, it had a 100 meter antenna and it managed to power a speaker which was fitted with a 2k to 8 ohm transformer. we had enough signal to actually light a LED. The transmitting station was 50kw about 10 miles away
100 meter antenna. I'm jealous. I make do with three 5 meter wires in parallel.
+John Doe Some old phones have piezoelectric crystals (in the shape of a disk) in them but I've never opened one up so I don't know the details of figuring it out. If you do have one with a piezoelectric crystal then since you're not powering it with any other source than the radio, you'd need to make some sort of cylindrical enclosure for it and a tube that can extend from that enclosure into your ear. You can use the diagrams on this page as a guide rimstar.org/equip/crystal_earphone_earpiece_for_crystal_radio.htm.
PS There's no Reply button under your comment because of your Google+ settings.
- go to your Google+ page,
- in the top, right corner click on your thumbnail icon,
- in the popup that appears, click on "Settings".
- for the 2nd question down "Who can comment on your public posts?" set it to "Anyone".
Since crystal radios only work on AM, do your crystal radios ever experience interference?
I don't connect it to ground. My portable crystal radio has two wires coming out of it that are normally for connecting to a crystal earpiece. I connect the amplifier's input to the wire that goes to radio's diode (stripe end) and the amplifier's ground to the other wire, which simply goes to a junction where one end of the coil meets one end of the capacitor. For improved performance I put my hand solidly on one capacitor plate, so that my body acts as a ground.
Turns out if you connect one side to the ground and the other input to the antenna, it works like a radio receiver by its self. By changing the volume i can kind of tune. It picks up AM radio the best, but also some times picks up FM radio.
also how do i make the amp louder even with the same set up not that loud
Great!
I have a question. I don't actually think I need a crystal radio because when I plug one input to the ground, and the other to the antenna, I get AM and FM stations. So what does that mean, I'm puzzled.
Ok thanks, I am not using this as a radio but rather an electrical switch. I don't want to delve into it but I am using an arduino instead of an oscillator chip and an op amp instead of the nte160. Thanks for your help. I can find somewhere else to get this info. The Mighty Google will tell me how to amp the signal. Thanks for all your help!!! wviper3
Thanks. Since there's no thumbs down, I'll assume it went okay! :)
Sir any RC project magazine , having different types of circuit's for RC toys with explanation how it works ,
Amazing and simple...
Can u put sd card and usb
LOL! I did that for you. :D
nice!! Can we use an ordinary audio amplifier IC (tda 7052)???
+mitropoulosilias I've no experience with the TDA7052 so I can't say for sure. A quick glance at the datasheet seems to indicate it should work, but without experience with it I can't say for sure.
One newby question, if you improve the antena size in your radio it's possible to collect more energy from radio station to power your device without battery? Thanks
I'm not sure about improving the antenna for this loop antenna but if you were using a straight wire antenna then the longer the wire the better.
What would be involved in making a crystal radio small as a mine volt battery with a very large listening range very long ant and ground would be a must I guess
Another great video! Thanks for the info! One question I have is would it be possible to build a 2nd LC set (using the same antenna) that is tuned to a radio station very near by (strong carrier wave) and use a bridge rectifier to replace the 9v battery? (I'm sure the voltage would be less than 9v, but you should be able to amplify the weaker signal that you want to hear at least to the same volume as the radio station that is more powerful/nearer, right?)
Thanks! I'm glad you liked it. Theoretically what you're suggesting should be possible but as you guessed, there isn't a lot of power in these received signals. I doubt you could power this particular amplifier circuit so you'd have to come up with something else. You might even need more than one 2nd LC set.
@@RimstarOrg Thanks for taking time to respond! I am collecting things to build a crystal radio now. I guess the best way to see how things work will be to build it and see what happens. Looking forward to future videos.
We are trying to build this and I need a simple question answered for these parts as I am NEW to this! What voltage should the components be rated for? Ex: I have a 10uF electrolytic capacitor rated at 50V, but I see you have a 9 V battery attached. Does this matter? Am trying to buy parts and all the detailed options are overwhelming. Thank you in advance!
The voltage rating on a capacitor is how much the capacitor can handle without breaking. So a 50V rated capacitor for a 9V system will definitely not break.
The power rating on a resistor (the number of watts) is how much power it can handle without breaking. For that you take the voltage that will be applied across it and multiply that voltage by the current that'll be running through it (power = voltage x current). But I don't know the current for this circuit. It's not much though, so even a 1/4W resistor will be fine.
Where can I find a copy of Radio Receiver Projects You Can Build at? What website? It's too bad that my bookstore or local library does not have this book.
+Adam Ebel I bought mine at a book store many years ago but try this www.amazon.com/s/ref=nb_sb_noss?url=search-alias%3Daps&field-keywords=Radio+Receiver+Projects+You+Can+Build
+RimstarOrg Okay, Thanks for letting me know. I will order the book soon. Thanks :)
Polarity only matters if you have multi-speaker setups. In this case, different polarity connections can cause interference patterns due to the sound being out of phase from different sources. For a single speaker this isn't an issue.
Interesting thing to try, but I don't know if it would work. Get some earbuds. Cut the cable going to one of the earbuds. Inside the cable are two wires. Connect the two alligator clips coming from the amplifier to the two wires. Plug the jack into your mobile. Try connecting both ways to see if one would work. But, those wires in the cable are extremely thin and you might need a magnifying glass to work with them. Let us know how it goes.
Thank you for share I make this one and work but when I connect to crystal radio is very2 weak volume on maximum potensio..any suggestion thank you very much.
A long, straightish antenna and a good ground are perhaps the best tips.
@@RimstarOrg ..next I try thanks
how do you connect the amplifier to ground
when using a portable crystal radio
Hey Rimstar, would it somehow be possible to replace all of those capacitors and resistor with homemade ones? What kind of calculations would you need to do?
I see that you're trying to make your am radio as "diy" as you can and thought it odd that this one was the odd one out!
I guess you could make DIY resistors. The capacitors would be trickier since microfarad range capacitors would be huge unless they're electrolytic. Luckily I do have videos on making electrolytic capacitors ruclips.net/video/ml2TdQ2_2mk/видео.html and ruclips.net/video/lmVVdV8wuB0/видео.html . You'd just have to do some trial and error to get the capacitance close enough.
PS. I saw your earlier questions on other videos but then I saw you got your answers from later videos. I'm glad you're enjoying them! Thanks for watching!
PPS. Since you asked for more low level videos with formulas, here are two normal capacitor DIY ones that talk about capacitance and breakdown voltage with formulas as the basis:
ruclips.net/video/GveI9gXIsHw/видео.html - low voltage caps, capacitance
ruclips.net/video/MPD7skZ8OSo/видео.html - high voltage caps, breakdown voltage
RimstarOrg can you teach us how to increase the power of your Amplifier or teach us how to increase power on amplifiers? like 60 watts to 300 watts
I made this from mostly de-soldered parts off an older circuit board, had to buy the LM386 to be sure, but otherwise all salvage. Only one question: This plays much much louder than the crystal earpiece ever did, but it's still too quiet to be heard across the room if it's not perfectly silent (on some radio stations); How would one go about boosting the output volume?
pricemac From the crystal radio's point of view you could use a longer antenna. Also, pointing the antenna at the radio station helps, though since it should be a straight wire that's no always possible. As for the circuit, it isn't mine so I don't know all the details. But looking at the LM386's internal schematic on www.ti.com/lit/ds/symlink/lm386.pdf possibly decreasing the size of the capacitor between pins 1 and 8 might help. If you study it further you might find other tricks.
RimstarOrg Interesting! I'll tinker with it. Fun note at the end describing frequency shaping, to compensate for poor speakers (like a bass boost). If I find something that works well to make the speakers sound nicer, I'll post the circuit to you.
(it suggests a 15k Ohm resistor between pins 1 and 5 for an effective 6dB bass boost, Bass Boost switch or button maybe?)
RimstarOrg So, After playing a little, I have to say reducing the capacitor did not work, apparently that value bypasses the default gain level of the chip, maximizing it. (Worth noting if it was too loud, you can change the capacitors out to lower it, just not raise.)
So, on to solution time:
I did a little digging, and found a diagram for a "one transistor amplifier" made simply for amplifying the crystal earpiece. So I used that amplifier, replacing the crystal earpiece's "in" cable with the speaker amp's "to diode" connector. As described by the tutorial about the "one transistor amplifier" it takes about 10-15 seconds to "warm up" (saturating the very large 8.2M Ohm resistor [or something like that]) and then begins playing loudly.
This is the tutorial I used for others interested:
www.petervis.com/Radios/one-transistor-radio/one-transistor-radio.html
I'll attach the complete radio circuit diagram once I make it look all nice and tidy.
Edit: Here's my Current Setup: drive.google.com/file/d/0B3GtbJ0uO52MU0V2RV9wVW9mcE0/view?usp=sharing
pricemac Sounds good!
also will this work with a portable crystal radio no ground
That's what I'm demonstrating at the beginning of this video. Although, to make it a little louder I cheat and if you look closely you'll see that I have the palm of one hand on the outer capacitor plate to give it a ground. It does work without doing that though, it's just quieter.
can we use this as an ordinary amplifier foe speaker,microphone etc...
Yes. I've actually used it for a great many more things over the years.
Hi there, I have made an amplifier about the same as the one you've made here but i was wondering if you could help me with some trouble-shooting? I used a linear potentiometer and i can only hear the radio at a tiny point when i turn the volume up or down and once I'm past that point everything goes quite. Are you suppose to use an audio/log tapered pot for this circuit? Could that be the problem? thanks heaps, any help would be much appreciated :-) great video by the way, i just subscribed and am watching more!! thanks
Dan brown My first guess is that your potentiometer has too wide a range. What's its maximum resistance? The fact that it's linear just means it would be harder to turn the sound up gradually. If it's a 10k one you should still hear it throughout the whole range.
RimstarOrg Yea its a 10k one. i haven't got round to plunging the amplifier into the actual crystal radio, i was just plugging it into my phones radio at a low output setting to test it out and thats how i have come across that problem. thanks for you reply :-)
I mean instead of the 10 ohm resistor not the variable pot would that work please respond before 3
That's quite a big difference. I suspect it's for filtering. If you put 10kohm then you may as well not put that part of the circuit at all. Many circuits don't even put that 10 ohm resistor and 0.047uF capacitor at all. i.e. Don't replace them with a plain wire, just don't put anything in their place at all, skip 5:06 to 5:16 in the video.
but if i want to play music from my mobile so how would i connect the head jack to the amplifier.....??????
How did you mount the switch and the potentiometer in the jar? Thanks, great video!
I simply made holes for them, put them through the holes, and fastened the nuts that come with them. See the video at 7:51 and 8:18.
Thanks Rimstar! I never mounted a potentiometer before and looked right past the obvious fastening nut.
Oh good. Let us know how it goes.
Great Video! I don't know a thing about electronics and was able to build a crystal set and the amp with these videos. I have one question, where in this circuit could I add an LED to use as a power light?
Julian Adkins Thanks! If you look at the circuit diagram on my webpage rimstar.org/science_electronics_projects/make_crystal_radio_amplifier_for_speaker.htm I'd put the LED and a resistor just to the right of the switch going from that red line to the black line immediately above it. The trick would be to find the right resistor value for whatever LED is used. In the first few minutes of this video he talks about determining resistance values for protecting LEDs ruclips.net/video/abWCy_aOSwY/видео.html Let me know how it goes if you do it.
Thanks RimstarOrg, I'll let you know how it goes.
RimstarOrg It worked ! Thanks again!
Julian Adkins Excellent! Thanks for letting me know!
Would it matter much if you connected a solar cell (or several) to a rechargeable battery so you could skip having to change the battery out in this? How would you do that? Would it make sense to bother with it?
Absolutely, it would make sense. Heck, you could even cover one side of the pizza box with the solar cells! I don't know how much power was being drawn by the amplifier so I don't know how many solar cells you'd need. If that's still not enough then you could put some cells on a panel that folds out from the box. If it's a sunny day then you may not even need batteries, just run the amplifier directly from the solar cells.
With the six-solar-cell panel I made here rimstar.org/renewnrg/diy_homemade_solar_panel_simple.htm I got 3.22 volts 1.81 amps with no load so it looks promising.
Sorry, I see you may not even be talking about using the pizza box crystal radio. I guess I got excited by idea. :-) I don't know anything about charging rechargeable batteries like AA batteries. You can probably buy charger circuit boards for lithium batteries as long as they take DC as input since that's what the solar cells provide. Have a look at what www.adafruit.com/ or www.sparkfun.com/ have to offer.
Thank you! I'm really enjoying your videos! I'm trying to learn what I can about all this stuff, and I appreciate your posting them and also replying so quickly :) I'll have a look at the links you posted here. Thanks for posting them!
Hey, I just checked out those links. I guess I wouldn't know a charger circuit board if it bit me in the nose. Also, I like the idea of covering the pizza box with solar cells, so long as they don't overheat and catch it on fire. But I still don't know how to set that up. I'm still going through your videos. I just found your channel tonight.
There's no danger of fire. With that small an area of solar cells, there won't be enough current to produce enough heat for a fire. I glad you're enjoying my videos!
Um, as long as all the circuitry is protected from the water, I think so. I think you'd be able to receive from surface radio stations. Not sure though.
dear rimstar i have a project with my friends tomorrow and i have to finish this tonight how fast can this be made and are there any shortcuts please answer back as quick as possible.
+RimstarOrg
+Armando Bravo There are no shortcuts. How fast you can do it depends on whether or not you have all the parts and what you experience is in making electronics.
Well we were looking up engineering projects and stumbled across the video on the lazer photoresitor and weve never made any electronic devices, and can i just hot glue everything together. RimstarOrg
+Armando Bravo You can hot glue things in order to mount them somewhere but the connections between the electrical components have to be electrical connections, done by twisting wires tightly together or soldering them together or using alligator clips.
they closed the radioshak in Atwater and I can't get the parts to build the amplifier just to ask I want to know can I buy one off of you homemade
+Andrew Kimble I get my parts from some local electronics stores, not chain stores though (we haven't had a Radio Shack for a long time.) Also I buy online, mostly from ebay.com but sometimes from other websites I find by searching on google for the part. And lastly, I get parts by taking apart things that people throw out. Looking at the parts for this amplifier, the chip and some other parts came from one local electronics store and the rest were probably scavenged from things thrown out.
And I don't sell things. You might be able to find a small amplifier online. Depending on what you need it for you might already have an amplifier, maybe a speaker with a built-in amplifier?
partsexpress.com They have everything...and a lot more
I got something to ask you. were do you get the parts to build the amplifier do. you go to the radioshak store were you live just to ask the closed the one in my city in Atwater ca. 95301
+Andrew Kimble There's one in Oakdale and one in Manteca.
partsexpress.com They have everything you'll need...and a lot more.
put your materials in description please thanks :D
how to deal without perboard/pcb/breadboard use enemeled coppoer wire as connectors and solder the directly
Hello steve sir, May i have the link for that book?
Here's one source www.amazon.com/s/ref=nb_sb_noss?url=search-alias%3Daps&field-keywords=%22Radio+Receiver+Projects+You+Can+Build%22+by+Homer+L.+Davidson
RimstarOrg Thank You sir ☺
I don't know. I didn't design the circuit. Judging by it's position, I'd guess it's to block DC along that path But I could be wrong.
It had a hum like it needed gounded?
Maybe. But it's also possible that playing around with the capacitances and resistances would help too.
Can I use a 51 ohm resistor? Pls reply
+samuel virgil pe I'm assuming you mean instead of the 10 ohm resistor. To be honest, I don't know the purpose of that resistor. The capacitor that's in series with it seems to be a filter, though that's not clear either. I'd suggest just trying it if you have it already.
Polarity of the speaker matters. It will work, but when correctly connected cone(diaphragm) will bump outside, not inside. This factor changes sound (particulary bass) at big volume. Thats just FYI. Nice video through. Excuse for my English :|
cool! thumbs up. i would say something about it, but i'm not into electronics, so i'll say cool again: cool!
How can you replace the battery? Thanks.
The 9 volt battery is just snapped on. Replacing it is easily done by pulling it out of the jar, unsnapping the old one and snapping in the new one.
Can i use 12v battery and bigger speaker?
The speaker I chose was just a random one I had lying around. You may be able to use a larger one and still get decent sound volume. From the amplifier chip's specifications (www.ti.com/lit/ds/symlink/lm386.pdf), it looks like it can handle 12V.
I use pref board with copper spots on the back.