Upgrading the Indian 5 CORE radio with Lithium Ion power
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- เผยแพร่เมื่อ 25 เม.ย. 2021
- Yep, I picked up a 5 Core T22 radio from India. It can only run on two C cell batteries, which I don't have in the house -- so I use an 18650 instead. Then I do a quick review of this radio.
VWestlife's Original Video:
• Searching for the last...
• Secretly made by Sony ...
Shango066's 5 Core radio review:
• Modern 5 Core AM FM SW...
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"AM is really hard to receive in my house"
~meanwhile, in his recycle bin: 300lbs of discarded RF shields~
The idea that "nowadays you don't need that anymore" rarely fails to make me cringe🙂
@@Breakfast_of_Champions in other videos, he's always talking about "Gotta use a good RCA with shielding" and I'm like 🤷♀️🤷♀️🤷♀️
Unfortunately my thoughts too. My original C64 was bad enough WITH the original shielding. As a DXer I'm glad I was the only C64 owner in our block, I could listen to the foreign radio broadcasts when the machine wasn't in use. I think the modulators (at least in the UK versions) were the worst culprit for RFI though.
@@KingMob4313 "Gee, i wonder why."
This video is a nice surprise! Looks like the 5 Core radio is going viral (first VWestlife, then shango066, now Adrian). At this rate, I expect to see 5 Core videos from Techmoan, Fran Blanche and EEVBlog by June. :)
Techmoan reviewing this would be entertaining. He'd either think it's amazing or hate it. Either way we can be assured of a lot of sarcasm :D
@@fadate7292 Good point. I should buy one of these radios now before the Techmoan Effect kicks in!
Mr Carlson's lab will be performing a complete recap and tuning in 4K video.
@@fadate7292 Hasn't happened yet, but yes, I fear it will. To think I'm not decided on buying one bc I can only find US sellers and shipping to Europe is 15-16 extra bucks. Maybe I should grab it anyway?
I think this radio is crap and I do not understand all the hype about it
I'm glad to be seeing electronics coming out of India. I recently noticed machine tools starting to come from India as well.
Andrews Wayback Basement 😉.
In Europe a lot of countries stopped transmitting AM radio years ago. Even FM stations switch to DAB+
Thank you for making these videos! Subscribed.
Well, it's all about range, of course. Europe is more densely populated and countries are "small" compared to the huge US & Canada territories. That's also why stereo AM was never a thing over here: music stations adopted FM as soon as possible with nationwide stations using relays.
Adrian, I’m glad to see you’re a lover of old radios. I am, too.
So, from the Digital Basement to the Analogue Upstairs? :P
Adrian's Analog Attic
@@chaerther +1
Also he said he had triple A's, so...
@@chaerther Came to say exactly this. 👍
Getting some Mr Carlson's Lab vibes, he works on old valve radios and the performance of a well tuned valve radio is surprising and the sound is magical.
Mr. Carlson is a crazy good electrical repair / engineering guru!
Yeah if he's a 10 out of 10 skilled technician, I'm a 0.5 out of 10! He's in such a different league than me. :-)
@@adriansdigitalbasement2 Oh no...9/10 at best. Mr. Carlson wants you to go on a journey and explore the intricasies of the analog universe and I actually use his videos to help me sleep. ;P
Your videos are the best
@@adriansdigitalbasement2 oh come on... you're not a 0.5... you just need to learn a bit more electronic theory... your troubleshooting skills are excellent and quite methodical sir.
Adrian; if you ever need help with the electronic theory, drop me a line.
Says “shortwave is useless”, makes me turn on my 1936 Hammarlund shortwave receiver 😂
I'm loving old radios too. Want more of this.
Adrian i love olde radios too! I buy old vacum tube ones and repair them. I love transceivers too, that's why i'm amateur radio too.
73 from M0IVC - CT9ABQ
These videos are a lot of fun! I really enjoy these and LGR Blerbs. It's also nice seeing different items that you can have fun with too!
Glad to see a radio on the channel 😁. The Sangean PR-6 is a true analog radio that is still available for purchase from a quality manufacturer.
I took a quick look at Amazon and it seems like people complain about the PR-6's AM reception -- while they do say the sound quality when you are picking up station is great.
I recapped my old radios recently... what a difference 🙂
I'm going to be doing that to my sanyo C44 soon (it works fine but when i plug stuff into the 3.5mm microphone jacks or the "RCA connectors" on the back it hums when running off AC so I'm going to try replacing the power filtering capacitors on the transformer and any that might be bad on the main PCB, but I'm not doing that until I get all the other parts I need for it.
I think the hum is capacitor problem for sure but also after recapping the radios gained more sensitivity and more loudness!
Yes, shortwave pretty much useless especially thanks to the guys that remove the EMI screen inside their C64
More Adrian's Digital Basement videos in my life? I'm in!
Rocking a pair of binoculars on the dining table! 😎 Keep up the interesting content, either analog or digital! 😊
There is something to be said for simple. I like this radio.
Me too! I have just bought a brand new JVC 9465LS! Can't wait to see it!
Didn't mention in the video but I found other stations on AM also had the same distortion when playing music with bass. Since AM is mostly talk, you don't hear it with voices, but anytime music is playing on any station, it sounds the same. No issues on FM...
UPDATE April 26, 2021: Thanks to viewer suggestions, I have added a regular diode to the battery connection going into the radio. This is to take advantage of the 0.6v voltage drop the regular diode provides. The radio is now getting 3.4v from the installed 18650, which should be exactly what it gets from regular Alkaline C batteries. These typically have a fresh voltage around 1.7v each, so 3.4v. Unfortunately, this had no affect on the AM distortion from bass -- so the diode isn't needed, and it will likely reduce the battery life of the radio.
Also, the C cell battery contact spring (which I'm not using) was vibrating when listening to music, causing this really annoying resonance sound. I installed a zip tie on it and then wrapped it in tape which eliminated this noise.
It's been a while since I've done analog electronics but IIRC, AM stations only broadcast a 5 kHz carrier, which covers the average frequencies of human speech. Your bass is probably getting distorted because you're receiving the bass frequencies, but none of the higher frequency harmonics. FM broadcasts on a 20 kHz carrier, which covers the entire audible spectrum, giving you much better audio fidelity but also using a lot more bandwidth. There's a lot more to this - accounting for sideband channels, spectrum gaps so stations don't overlap, and clamping down on rogue harmonics - but that's a whole other topic.
Also not an expert here, but I think the bass distortion is a reception issue. IIRC, the way AM works, it's rather easy for spurious signals to induce distortion in the amplitude. So maybe it's the same result as Shango, but because you don't have as powerful an AM station like they have in LA, you are just getting lousy sound instead of total overlap. I think this is one of the main reasons people switched to FM.
I don't think it's this. The distortion seems to happen right in the middle of the AM station -- if you tune off to either side slightly it goes away, but that also reduces the overall received signal level and you hear a little noise. I'm thinking that the front end of the AM tuner just can't handle the signal level of the powerful AM stations? Either that or I just need to try to filter out the bass from the AM reception since the small speaker in this radio can't produce much bass anyway. Just had to know if this is a fault or a design issue with the radio.
@@adriansdigitalbasement2 the am distortion could be simple overdriving due to the preamp or amp low pass not attenuating the base signals enough; in essence if the amp is only using a traditional low pass and it's set someplace between the fm expected output gain and the am expected gain for "good enough results". You would need schematics to be sure this could be as simple as a capacitor across the preamp output. If the problem goes away as you move away from the transmitter on am this could be the case. Sometimes there's a variable capacitor/resistor set on the preamp output that is usually glued with epoxy.
@@adriansdigitalbasement2 I believe you are correct, the front end of the radio is getting saturated, and the IF section is unable to handle the RF from the detector circuit. This would tend to be more pronounced in the middle of the band, as you suggest.
Good on you for using battery protection. I see plenty of hobbyists treating 18650's with complete abandon, because they're used to pouch style LiPo's with integral protection.
Nice to see Shango listed in the description, I was just watching one of his TV repairs lmao.
I could do without Shango's bullcrap conspiracy theories though.
I did that same mod to an old Radio Shack radio - that board has protection so it won't discharge below a certain point and damage the cell (assuming it's working correctly).
As someone who has a (very small) collection of around 20 old radios I really enjoyed this video. I think that for the price, the 5 Core is a decent radio. I also think that you should recap the Airline to see if it improves the performance.
Thank you for posting this. I never would have noticed that there is plastic to remove on mine.
Love the look of the Ward Airline transistor radio
I.... I don't understand. Where does the joystick plug in?
Yes, I think overpowering the radio 25% (4v instead of 3v) is causing the AM distortion.
Making nostalgic for my Art Bell listening days.
Oh Adrian! Monday is such a slow day in my youtube bubble and I sit here desperately and press refresh to find something to ease the existential horror of my MS-Word drudgery. And then, like a shining beacon, you part the darkness of useless video recommendations and enlighten me ... with Lithium Ion Power. \o/
I enjoy the vibes of the second channel
10:17 that output has only low voltage , over current and short circuit protection. It has a double mosfet and dw01(i think) ic to protect the battery .
Oh boy now you've gone down a whole other rabbithole with radio... DXing (trying to pick up not-local-to-you stations) got me into electronics and amateur radio as an adult. Even though there isn't as much variance of content on AM radio compared to when I was a kid in the early 1980s, it's still FUN to try to pick up distant stations with small radios!
A pocket old school FM radio is actually one thing I take on holiday with me where ever I go - abroad or here at home in the UK, camping or staying in a hotel. No matter where you are on this planet you should be able to pickup a radio wave of some sort.
I AM FROM INDIA and I get some interesting stations on my Sony transistor radio. I GET Voice Of America, B B C London, and some neighbouring countries. WILL buy the Indian Radio you were testing in this video.
Thanks for the interesting video.
I cant find this in india now
The little section next to the battery cavity would be for the power cord. It was a standard feature on a bunch of appliances back then. It's supposed to be portable so they'd hide the cable in there.
If you watch vWestlife's video on the radio's disassembly, he shows that the compartment was way too small to hold a power cord of any substantial size and length. As other comments point out, it was most likely for a third battery back when the radio circuit the case housed would have used a 4.5 volt system.
I like the late tube radios that got miniaturized (probably at high cost)
I've made a quick count of the amount of radio receivers I have in the household. They added up to eight, two of them have analogue tuners, but three receive AM frequencies. I wish there were more radio stations in my area. I'd definitely tune in for a dedicated sports channel.
If you look on Ebay, the 5core company makes not just radio stuff like speakers and so on (which they make a ton of), but personal care items like electric razors, hairdyers, and so on. Plus some kitchen stuff like air fryers. They also make a Basinet?! Hope the edges on that are a little less rough then the radio.
Used to have a hand built crystal radio back in the day.
Find and fix a 1941 Philco 280 so I can avoid screwing up the one I found next to a road. :-) Love the Shango!
That output is for protection of the battery so that you don't over discharge the battery. I advise using it if possible.
I have that GE and that 5core.
I'm happy with both
I saw other reviews, this Indian 5 CORE radio is working very well, if you love camping or some outdoor activities, you should get one.
If the voltage is a bit too high you can connect a 1N4007 in series, which reduces by about 1 volt without consuming amps.
AM DXing was one of my favorite things to do as a kid, even though I didn't know that's what they called it. I had an old Radio Shack radio with full analog tuning, and on some nights, I could get radio broadcasts all the way from Nevada, Utah and Colorado (I'm also in Portland, so all of those states are hundreds of miles away). While I could probably do it these days with a SDR, I'm actually tempted to get one of these to mess around with it.
You promised candy-videos on your second channel and all we got is some more tech-videos. :)
I'm amazed that anyone knows how to make an analog radio receiver anymore.
Know how is easy. What surprises me is there are any companies that still care given how tiny the market for analog radios in particular is small
I have a little Tecsun AM/FW/SW/LW/Weather radio I keep around for when I'm working outside, or go on trips or whatnot. There's plenty of time when you don't want your phone out but you want to listen to something.
There is so much to dislike about this radio but all of it makes me like it even more. It's kitschy and cheap. But it tunes well and the sound is really good. I'm glad I got one!
I love little transistor radios my uncle gave me one from like the 60's or 70's when I was a kid I used it all the time they are great for camping you can buy them for cheap and if you take them camping and they get ruined it's not a biggy I collect them find a lot at thrift shops they also work great when we lose power as well. Like I said I collect the little pocket sized ones are my favorites and they tend to be easy to find at thrift stores and new ones can be gotten for ten to fifteen dollars.
Adrian! You are not allowed to complain about RFI until you reinstall the RFI shields on all your C64s! :)
That bleed through that heard when on the short wave band would be from AM as AM and short wave use the same 455 KHz IF oscillator. If there’s a radio station on 910 KHz that would contribute to bleed through as well 455 IF frequency x2 = 910 KHz
The guy on the box is not mountain climbing like you said... however he is "abseiling"! 😎
I love transistor radios too. I have a old nice one that needs restoration and cleaning. Maybe I'll clean it up and do similar Battery mod ☺️
I too am partial to a radio or two, or three or more! Very interesting!
I wonder if you will start receiving a bunch of radios in the mail now. :D
LOL! I did scratch my head and thought about offering one of mine
I have a few I could send you! :P
I think the key to the climber is that stuff hanging off his belt. Looks like a bunch of chocks and nuts. These are climbing aids that are put into cracks in the rock face by the lead climber as anchor points. The trailing climber, which appears to the one depicted on the box, collects them while climbing past. (These are not new, going back at least 40 years, but I only know about them because of reading an article about a mountain climb in National Geographic decades ago.)
I would like to use something that is an 18650 but I want to charge like this and then output 5v to the radio and other gizmos I will be adding. I also found that 1A output isn't enough either. Any suggestions would be great!
Adrian; look up the term thermal inversion and propagation, for more information about why you can pick up radio stations from far away locations.
Seems like a decent radio, I'm always watching for one to use to listen to baseball in areas where reception is questionable. I may have to check it out. Great idea using the 18650 cell, they seem to last through a lot more recharge cycles than their C or D cell counterparts.
Actually if a C or D NiMh battery is taken care of it will last a while longer than a lithium ion battery, I still have batteries I got in 2012 that still work and have good capacity while my phone's battery from 2018 is already starting to go bad
The overdrive on AM may well be the overvoltage of the 18650. You may want to test it with 3v from the bench power supply to see if is better. If that is the vase you can just add a 3v linear voltage regulator or a zener in the battery to drive it with the proper V
Vase = case 🤣
So when does this channel get renamed Adrian’s Analog Attic?
Here in the Bay Area we have an equally strong station as KNX called KCBS 740. It can be picked up as far as Colorado at night, or so I've been told that is. AM radio is very interesting to me.
Would have been a cool joke if you played a snippet of Orson Welles' narration from The War of Worlds radio play whilst you were turning the tuning dial. :D
I got a thing for panasonic radios. Whenever I see them, I buy them.
It would be neat if someone would design a case worth a damn for the 5 Core. Laser cut wood or acrylic would be fun and probably sound pretty good.
I'd love to know how many millions (tens of millions?) of cases that the 5 Core's tooling has made since 1984. It'd explain why these radios look a bit rough around the edges.
I need one of these.
Maybe if you put all those shields you tossed back in the C64's you would have a less noisy basement.......
The buzz goes over power lines and concrete rebar if you have any in the walls. You gotta go out of the house some 10 meters away. You could probably get a used boombox with a casette player and get a similar radio performance with a single compressed SW band.
Try going outside to see if the antenna matches the polarization as it should. It helps with imaging on SW if the FM stations are horizontal.
Nice review. I ordered one from Walmart Com with free shipping. You would need a long wire for shortwave AM.
I remember in the UK AM was actually separeate from MW. We had FM, AM, Medium Wave, and Long wave, and possibly Short Wave, I can't remember
I think the output pads on the charging board might be part of battery protection circuit on the board. It will cut the voltage to the output pads off when the battery is discharged to protect the battery. It might be worth testing as it can help you make sure that the battery lasts longer. (Regularly overdischarging li-ion batteries reduces their usable capacity really fast) If you see a tiny SOT-23-6 package chip with DW01 marking that is one of the most common battery protection ICs and a good indicator that might assumption might be correct. Cheers
Quick questions:
A) How do these two models compare T-22 vs T-291.?
B) How’s reception in the Shortwave band?
Cool radio.
How Strange not available in India. From an Indian viewer. My father is very fond of radio i brought a Philips radio in 2013 which was true analog but it broke after 4years. I brought another one same model from Amazon which was completely digital tuner based. Although the casing And the model number was identical. Digital one serves the purpose fine only one government owned am station is good for reception. Which he listens regularly for news.
I once connected a USB micro B socket to my radio, which runs on 3 D cells, (4.5V)
I used power bank to power the radio.
That's ofcourse, 5V.
so the MW had a whining noise in the background. Sounded like triangle wave or something...
Ham radio operator here, neat to find a real analog radio like this, even as super cheap and janky as it is.. All the modern stuff is digital, although there are still half decent SW/MW/FM radios out there. Not too many though.
might have to add a 3v regulator to the LiIon circuit
COLOR FYI: Kdenlive video editor (free) has a "White Balance (LMS space)" filter that can fix overly warm color spaces by letting you select a region in the scene that is a neutral color. I use this all the time. Available for Linux or Windows. Great for fixing videos with ugly colors.
Thanks for the tip!
16:23 You should have the antenna horizontal. That is why you get better signal when you have it down.
4:17 the rappelling down is definitely a statement on their quality and reliability.... heh....
You got a 5 Core Brown Box! Mine came in a USPS box. Your box is valuable! 😂
I'm sure you already know about this, and it's not quite the same thing at all - but it's a lot of fun! You could probably make videos about this as well - RTL-SDR is a very inexpensive ($15 Ish) hobby to get into. Of course you can spend much more. If your basement bunker gives you reception issues, you can use a RasPi with a dongle and antenna mounted much higher up and use your WiFi to access it. AM, FM, shortwave, CW, NOAA weather imagery, ADS-B, some Space X video and telemetry, some cubesat stuff that I'm not familiar with, and many other things. Of course you'll need the proper setup depending on what you want to listen to (e.g. shortwave requires an upconverter for the very inexpensive dongles, and antennas matter). I really enjoyed watching thousands of planes in realtime monitoring ADS-B on a map with a simple antenna and cheap setup!
Maybe a simple voltage divider if you're worried about over voltage on the components?
Maybe try some voltage regulation to 3v to see if that makes any difference on the AM sound quality?
5:43 - I simply assumed Shango's antenna was all rusted out from sitting out in the elements for 30 years! :)
I like the old radios but I really like short wave radios
The compartment was to store the AC cord. I have the same arrangement in several old radios I have.
No, Shango066 showed that little compartment was way too small to get a cord into.
Hi,
A few of things that maybe of interest?
1) From what I remember the radio did sound different as the battery was going flat. Similar to your bass problem you demoed, but I guess if you are giving it 4v with 2 batteries it would normally get 3v?
2) I remember my radio use to come with instructions to pull the antenna out different amounts for different channels right out for am and only out a little fm etc.
3) the problem you described with the station taking up the dial is called broad banding.
4) It is common for radio stations to have harmonics so you can hear them on other bands than they broadcast e.g. like you were hearing english music on sw.
when I do conversion like this (and probably everything battery powered I own is modified to some sort of lithium battery at this point :)) I like to use buck/boost converter and feed only voltage device expect to it. Here I would use two 15650 as there is enough space for them, little buck converter and same charging board you used. There will be some self-discharge effect it there is no additional switch to turn of converter power but it's minor with most converters I try (just cheap AE stuff mostly) or with little effort can be bypassed to device power switch. With device like radio it would be wise to skip cheapest versions as they give noisy output and spend 20 cents more.
With low current devices like radio even 3V fix LDO is option, heat loses can't be too high (probably, you should check how much current it draw before and do a math).
the big AM I have is a philco model 70, and its picky on what it picks up
I dig this video. One thing I noticed is you never extended the aerial once you went upstairs. I could tell the unit was lightweight and seemed liked cheap plastic but the sound was decent (considering.) Maybe you did extend the antenna and forgot the show it but if not, maybe try that.
I can not find one of these for sale any where
Portland to Vancouver is about 300 miles as the crow flies. The climber must have been descending unless he was using a grappling hook which isn't really done.
That's fancy. I would just charge the 18650 in my 18650 andonized aluminum headlamp and solder in the 18650 battery holder. This 5 Core sounds better at some moments than others. There are two different versions. The Walmart version you have and the Ebay version with the 6 blue squares on front. Usually the blue square Ebay version sounds better. I wonder if the added voltage with the 18650 gives it a boost? Ok it sounded better at first and then worse with that distortion.
Many AM radios suffer from an intermodulation distortion where bass audio distorts voice audio. It's commonly caused by the AGC capacitor being too small allowing low frequency audio to modulate the IF amp's gain.
Use a few high drop diodes to get the voltage correct.
For Shortwave radio you'll need a SW antenna, like a 20 meter of wire up in the air, the other side propprrly grounded.
Try that bc-r21 from India for five bucks. Or compare it with an allband ATS-20 from Poland, which has an excellent chip in, better receiption compared even to a Malahit! Just my Kenwood TS-2000 will smoke 'em, but that's expected.
Guess the el cheapo ats-20 is the best radio receiver you'll get for small money, excellent chip in there and does cw ssb/lsb/usb, too.
Just my old allband tube radio Loewe Opta "Planet" from 1959, well, unbeatable. No modern electronics has such low noise levels.
What frequency short wave? The 15Mhz band has lots of talk and music stations on it as well; some are AM and others are SSB.
A lot of it depends on where you are. I live in the same place as Adrian (Portland), and I've never had much luck receiving shortwave, even with a high quality SDR and suitably long and reasonably highly placed antenna. I could get WWV, (the time station), a couple religious stations broadcasting out of Florida, and the occasional station from Asia if conditions were just right, but reception was consistently horrible and I never could get anything else. Apparently if you live in the eastern half of the US, it becomes a lot easier.
@@Damaniel3 tropospheric ducting can affect the propagation of the signals, as can the solar cycles.
I have a superstar 2000 if you would like it?
The hissing sound is due to electrical and electronical instruments causing interference surrounding all over us on MW, check it in open space away from interference, you don't get hiss..
The Bio Guru Anupam Tripathy - Most IC sets including even Panasonic make motor beating sound in AM beyond 3 volts. Although this radio allows 3 volt, he has used a 4 v rechargeable battery, so the problem in AM.