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Table top am/fm radios
- Thread starter rxonmymind
- Start date
maxhifi
Addicted Member
Any decent electronics text from the 20th century will teach you how a normal capacitor tuned radio works. As for the new style, I recently bought a CRAIG radio with this sort of tuner IC, so I read the data sheets to learn about it and why it works differently than the older radios. If you're interested the part number is KT0936MB9. Lots of youtube videos about this too but im not sure exactly titles, etc.
Images below: photo of the IC in my CRAIG radio, and underneath block diagram of same IC. I'm convinced the superhet has finally been made obsolete, this radio works great!
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charles 1973
Super Member
I wish I kept my GE Super Radio II to see how well it would stack up against my Bose Soundlink Color Bluetooth speaker. I pretty sure the GE radio had a clearer more transparent sound on FM then my Soundlink Bluetooth speaker using Spotify Premium through Bluetooth.
They both produced surprising bass for their size, But the bass from the Bose seems blotted by comparison. If I use the analog input on the Bose, the phones EQ, and place the Bose in the right spot it sounds quite good with Spotify.
I also had a vintage Realistic table radio like this that sounded pretty good.
They both produced surprising bass for their size, But the bass from the Bose seems blotted by comparison. If I use the analog input on the Bose, the phones EQ, and place the Bose in the right spot it sounds quite good with Spotify.
I also had a vintage Realistic table radio like this that sounded pretty good.
audiotemp
Super Member
Thanks, I looked at a datasheet.
The front end in that chip functions pretty similarly to the front end of a typical 1980s or later FM tuner, with the incoming RF signal amplified and then heterodyned (mixed) with a "digitally synthesized" local oscillator. There may be some differences in the details but not any that would affect performance. "Analog tuning" is provided here by a variable resistor with its wiper connected to the input of an ADC---which just translates the knob position into a discrete channel code for the synthesizer. This is an interesting solution to the "up/down buttons suck" problem but that part of the circuit is still basically 40 year old technology.
The datasheet glosses over whatever RF domain filtering is done (there has to be some) and the IF used in the chip is much lower than the traditional 10.7Mhz. The real "digital" technology in the chip is that the IF (down-converted) signal is immediately digitized and subsequent processing is done in the digital domain. At the block diagram level, the functionality is quite similar to the Si Labs' digital tuner chips.
I was curious about the Sony mentioned by @REMINGTON700 in part because Sony sells (or previously sold?) a fully analog radio that looks more or less identical to that one.
Radio Shack had some pretty good ones back in the day...there were two walnut-cased models, think the smaller was called an "MTA-5."
We have been pretty disappointed with the Tivoli, 45 miles from Boston and just too much "fuzz" and what I think of as multipath-distortion.
We have been pretty disappointed with the Tivoli, 45 miles from Boston and just too much "fuzz" and what I think of as multipath-distortion.
maxhifi
Addicted Member
https://radiojayallen.com/three-sony-portable-amfm-radios-icf-506-icf-19-icf-801/
^^ That might help. Interesting discussion! I for one like this new sort of radio.
NH-MAN
Addicted Member
Absolutly, I posted one of these earlier in this thread. They are like laying in a cloud listening to music
charles 1973
Super Member
That MTA 5 looks very much like the model I had. All 3 knobs where small, no large tuning knob and it had the walnut case. I was very pleased with the performance of the RF stage and sound quality.
FauxHall
Super Member
Just back from an overhaul at the RAW shop in Dubai.
Nice bedroom system (with the right CDs!)
Still have fond memories of my Advent 400 with the great assortment of FM stations back in the San Francisco Bay Area. I was a bit disappointed in the yellowing of the bright white plastic case though. Supposedly there's no remedy.
Nice bedroom system (with the right CDs!)
Still have fond memories of my Advent 400 with the great assortment of FM stations back in the San Francisco Bay Area. I was a bit disappointed in the yellowing of the bright white plastic case though. Supposedly there's no remedy.
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audiotemp
Super Member
There is a remedy reported for polystyrene yellowing, aIthough I have not seen it tried on an Advent 400. Google "retr0bright".
WilliamTK40
Member
They can be remedied. It involves some kind of mixture made with hydrogen peroxide. The downside is that the yellowing will return at some point and will likely be worse than it was before. This is a common issue with any electronic product made with beige molded plastic.
As far as my own table radios go, I have the following:
CCrane EP-Pro- got this one from a local ham who sells antenna accessories and radios as a sideline to his main business. It's a very good radio and I'm glad to have it. Sound good on FM and does AM DX very well, but I think that antenna adjuster is more of a gimmick than a useful, necessary feature.
Realistic MTA-15- Got this one recently at a thrift store. Its FM reception in my suburban area is pretty bad without an external antenna, and it suffers from FM multipath in a way that none of my other radios have ever done. Its AM is quite good especially considering its pathetically small ferrite antenna. I know size doesn't always matter, but I can only wonder how it would do with a ferrite bar that's more appropriate to the size of the radio. That said, the sound on the local stations I use is very clear, almost better than my CCrane. It's DX capable, but tends to only get the strongest of clear channel stations.
In the portable tabletop range I have a Grundig S350DL that I got for less than $20 because it wasn't working. I opened it up and it was full of cold solder joints. I got it working, and it's pretty good, but maybe not absolutely great.
Also have two 5Core T-291 radios from India. This is a true analog tuning radio on a chip with a varicon capacitor. I have two because the first one arrived with something rattling around in the case, and I requested an exchange from Amazon. They told me to keep it and they would send another. These work well enough, though the AM seems to allow a strong station to crowd the band a bit. THere's a place on the circuit board that appears to be for a ceramic filter that's jumpered with a wire, so I may experiment a bit and see if a filter might tighten up the AM bandwidth a bit.
In the past, I had a Tivoli Model One. It's FM had a nice sound and the AM was good enough, though I was hoping for better DX performance out of it. That's not its niche, though, so no need to try and make it do something it's not made to do. I'm thinking about getting another one, or one of the other radios that's similar from Sangean, Boston Acoustics etc.
-Thank you,
-William
Gnesen
Super Member
i bought one of those for my mother. It does sound really good.
rxonmymind
Super Member
Snagged one! A Craftsman AM/FM/Marine band/SW Foreign/Air & Police band radio.
Now only if I can get it to work consistently. It seems the Air and police band have moved on as it's completely blank. Same with Marin band. Am & FM still works. SW is spotty with maybe couple channels coming in. Not sure if it's bleed over from am tho.
Obviously I was born too late to enjoy such a radio. Even if it was fixed up with all caps replaced to new condition I don't think I would get the channels such as Marine or police. Dang.
Listening to Eddie Cochran right now.
Jeannie, Jeannie, Jeannie....
Now only if I can get it to work consistently. It seems the Air and police band have moved on as it's completely blank. Same with Marin band. Am & FM still works. SW is spotty with maybe couple channels coming in. Not sure if it's bleed over from am tho.
Obviously I was born too late to enjoy such a radio. Even if it was fixed up with all caps replaced to new condition I don't think I would get the channels such as Marine or police. Dang.
Listening to Eddie Cochran right now.
Jeannie, Jeannie, Jeannie....
Attachments
anytune
Super Member
I have this same model in the kitchen. $10 at Goodwill and it works great!
My neighbor had this Sony radio (https://www.amazon.com/Sony-ICF-506...769&sprefix=sony+fm+radio,aps,142&sr=8-3&th=1) on his deck when we were having a barbecue and I was pretty amazed at how good the sound was. It's mono obviously, but sounds very good for something so small and $50 new.
