So I have this old transistor FM radio with expanded spectrum

Try twisting some of them tuning transformers

Well I did try, bit there are only 2 which actually have any effect at all, but they just seem to adjust the volume...

Can we get some more info about the radio, like photo of its circuit board?

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There you go, red and blue wires are 9 VDC, black wire is antenna, and the smaller IC is KA22427, the second one is unreadable

Oh damn I didn't know that it's ferrite rod is static, sorry man but I don't have a clue... Maybe it's just the limitation of the radio, it looks pretty old

>>1125853
check wires under ferrite core.

and caps if blown specifically the middle one looks bulgy otherwise probably take less time to build a whole new radio than pinpoint the exact cause.

>show us the other side of the board and Antennae.

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Caps are OK (at least visually), and antenna is just telescopic metal stick (I need to position it in order to receive some signals, so I need to move it frequently)

Btw orange and black wires are connected to 1W 8 ohm speaker

Fiddle-fuck with the tuning screws. That can significantly affect your selectivity and if worst comes to worst you can use the screws to tune out parts of the spectrum. Unfortunately it's a trial and error affair so get twisting.

Also look into getting a new radio if you're not desperately poor because holy shit man. A Tecsun PL-680 or PL-660 (if you're cheap) will be an infinite improvement over that thing.

Actually I was looking for different radio, however every single one I got was without physical coils so I could not expand its spectrum, but the search shall continue!

>>1125877
>>1125874
Get an rtlsdr. You can find them for 15-20€ and can listen from 30-1900 MHz. There's a lot of free software which you can use with them to decode anything from ATC to weather satellites and digital cop radios.

More info: http://www.rtl-sdr.com/about-rtl-sdr/

>>1126096
How many walk in stores carry those?

>>1126271
Not many. They're mostly an online thing.

>>1125853
That circuit board looks filthy. What is that crap all around the IC's? This almost looks like it has been wet or something spilled in it.

>>1126793

it's just wax, dude, so cool your tits.

The information you've presented here makes no sense.

First of all, is that radio even designed to tune up that high? I can't seem to find that radio on the internet so I can't lookup the model of radio and check the specs. Looking at that tuning range, it doesn't appear to cover up to 120 MHz, it stops at 108 MHz. Which lends me to believe that some one may have modded it by reducing the selectivity and allowing signals to leak through the bandpass filter(s). You will need a signal sweep generator to help "tighten" up the filtering, possibly with limited results.

Secondly, since when is ATC frequency modulated? It's AM for a reason by ITU standard. The circuitry for the 88-108 MHz spectrum will do FM only.

And as the other guy mentioned, it looks like there's some corrosion around some components and the radio case is pretty beat up. The axial capacitors look new compared to the rest of the board, leading me to think someone has done a hack job. :-/

Just saying.

>>1126800
lol! my tits are frosty. I recognize the sealant, its the other crud around the IC's and parts of the board. Having worked on marine electronics it looks like this has been in a humid environment.

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>>1126803
I assumed it had airband by what OP said but with some googling it looks to be a cheap AM/FM clock radio only.

I'm not surprised its poor then.

>>1125833
One of them small copper coils next to the tuning capacitor are what sets the tuning range, up to a point.
By stretching or squashing the turns, you adjust the tuning range and to a degree the selectivity of the receiver.
The only real way to adjust the selectivity of any receiver is to align the sections with an oscilloscope and an RF generator.