Radio receiver on TA2003P

[jan]

Hi!
I would like to build a simple AM longwave/FM receiver using TA2003P integrated circuit. There are only few components required, but I want replace the AM detector filter with coil 7x7 233. Is it possible to work with it, and what do you think about this IC gererally?
See you
Jan

 

[transistor495]

Jan,
It looks like a nice radio circuit with supply voltage down to 1.8V.
It's a Toshiba IC. So it should be a nice performer. Try it. Wish you good luck.
A TDA7050 can be used for audio amplification.

But I'm a bit doubtful about it's availability

 

[audioguru]

The Toshiba radio IC was used in cheap clock radios about 10 years ago.
It is not sensitive and it is overloaded by strong local stations.

It is a little better than the cheap "scanning" FM radios at The Dollar Store.

 

[jan]

I have tried if it is able to work on longwave band. And - it is (excellent reception Polish, Russian and Czech transmitters) so I am collecting parts to finish the project.
Well, the FM is not so bad - it is possible to increase its sensitivity by using longer telescope antenna or adding one-transistor HF preamp connected directly with band pass filter. And the selectivity - good enough as for popular class radio - there were no a lot of highly selective radios tunned with variable capacitor not a capacitance diodes.
Best wishes,
Jan

 

[Hero999]

Where do you live?

I take it, it's in eastern Europe.

 

[transistor495]

forgot!

Oh dear I forgot, TA7368P is the suggested audio amplifier brother for TA2003P constituting a pretty decent radio.
I've tried TA7368P as my rechargeable ipod amplifier and found a pretty good performer with minimized external components. If your radio part is OK, then the rest of the things will be handled nicely by this performer!
I'm attaching the amplifier circuit which I followed for u(1.1W max,2-10V).
3-4.5V will be the ideal supply for the combination.

 

[audioguru]

Oh dear I forgot, TA7368P is the suggested audio amplifier brother for TA2003P constituting a pretty decent radio.

The Toshiba TA7368 has very low output power into an 8 ohm speaker when the supply voltage is low. It needs a pretty big output capacitor because it is not a bridged amplifier. A bridged amplifier does not need an output capacitor and has 3 time to 4 times more output power.

The 100uF output capacitor cuts all bass frequencies below 200Hz.

A TDA2822M is a bridged amplifier that has an output power into 8 ohms of 920mW at clipping.
There are newer little amplifier ICs that use fewer parts.

 

[jan]

I agree with you Audioguru - the IC suggested by Toshiba (TA7386P) has very small output power. So I won't use it in this radio. I am planning to use KA2206 - rather old or better TDA1904.
I could use also some better radio ICs - TBA1220B or TDA7512 - it would be great. But there are some problems:
- it will be my first radio so it shouldn't be very complicated;
- I don't have any frequency meter so I am almost unable to tune it correctly only by hearing the voice quality;
Yes, you are right - I live in the East Europe. So don't be angry, please, if I will make (or already have made) language mistakes.
P.S. I am going to develop my skills connected with electronics so the next of my radios must be much better.
Best wishes;
Jan

 

[audioguru]

The "better" radio ICs are tiny surface-mount with 64 pins or 80 pins. You won't be able to solder them. They are extremely complicated radios that need a computer with a program to control them.

My first radio was an FM stereo tuner kit. I tuned it by "ear". I think modern kit radios are junk.

 

[jan]

I have found a IC TA8164P. Is it a better version or TA2003P and how about this integrated circuit in general?

 

[mvs sarma]

I have found a IC TA8164P. Is it a better version or TA2003P and how about this integrated circuit in general?

this chip is made in 1997 around. Thus we may not call it a better version.

 

[transistor495]

Actually TA2003P doesn't need any IF transformers and 8164P requires them! 8164P is a later version I think, may be better performance. So making an fm radio out of TA2003P is really simple.
These chips are intended for use with only 3V supply and thats y TA7368P is suggested for audio section by Toshiba.

TDA7052 is a better performing BTL IC that doesn't require any external components and provide 1W at 6V supply into 8ohm. Better than TDA2822M.

Both TDA7052 and TA7368P eliminate any chance of getting oscillated than the TDA2822 and LM386 which have a mess of components scattered over the pcb. Noise too!

 

[audioguru]

The datasheet for the TDA7052 from Philips has no curves. They might be hiding something like a poor frequency response or high distortion at high output levels.

 

[jan]

Despite this I know that really good working radio needs advanced technologies, I will choose the TA8164P not TA2003P. Even if two more elements are needed it, hope so, will be working better than TA2003P. Especially if I don't have troubles with parts.
And my last question about the radio - is it possible to replace the 15pF capacitor that is coupling the LC circuit of FM oscillator with a smaller, something like 10pF and how it will affect the quality of working?
That will be all, I think, about the project. Thank you all for your cooperation.
I will inform you when I build the radio.
Best wishes;
Jan

 

[jan]

I have tested the KA2206 and there are some problems...
I think that it is not sensitive and the output power (tested in stereo mode) is much more smaller than 2,3W as it was advertised in the datasheet. It was tested in such conditions:
- audio signal from computer
- voltage 12V, excellent filtration
- standard 4Ω speaker load
Is the IC faulty? Should I use it in the bridge mode or replace it with LA4425 or TDA1904?
I am looking forward to hearing form you;
See you;
Jan

 

[audioguru]

The Samsung datasheet for the KA2206 has no curves. What are they hiding?
The FCI datasheet shows a typical output at clipping into 4 ohms with a 9V supply is only 1W.

With a 9V supply its typical power into 4 ohms with a horrible-sounding 10% distortion is 2.3W per channel and is a minimum of only 1.7W. At only 0.25W its max distortion is a horrible 1.5%.

I think it will melt if it has a 12V supply and 4 ohm loads.

 

[transistor495]

Ok, I've searched through my junk box one week before for a different purpose and accidentally found a radio receiver board I purchased quite a while before. The circuitry was based on TA2003P and I remember I've taken out the audio amp section TBA820M from it just because it was one of the worst and crappy receiver I ever seen!

It was for MW(550-1600KHz) and FM.

The receiver has no any clues for connecting an MW antenna coil with ferrite. But it received MW band with a lot of noise and distortion. I think it used the FM antenna for receiving AM and it still remains in my memories how the tuning cap was connected and reception on MW. I didn't test on the FM band.

Periodically I've taken out almost reusable components from it and now only I noted the IC part number. May be a badly designed receiver. Don't know. A really outdated IC my opinion.

I was a kid when I purchased it around 10 years before . I've gone through the anatomy of almost components including IF cans and played well!!

 

[jan]

So what do you think about LA4425? Is it better or worst than KA2206?

 

[audioguru]

So what do you think about LA4425? Is it better or worst than KA2206?

The Sanyo LA4425 datasheet says it is the very first IC power amplifier so it is extremely old.
It is single-ended so it needs a huge output coupling capacitor and its output power is low. Modern car radio amplifier ICs are bridged for almost 4 times the output power. They do not need a huge output coupling capacitor.
Like most car radio amplifier ICs its idle current is high.

The datasheet has its output power only at a horrible-sounding 10% distortion.
It is an old not good amplifier IC.

 

[jan]

The last chip which I have is TDA1904. What about this one?
If you think that it also is bad, recommend me, please, an IC according to my clues:
- voltage 9 - 12V
- 4Ω load
- gain about 30dB
- maximal output power 3 - 5W RMS
- distrotion as small as possible
- easy montage of heat sink
- low frequencies cut-off some 80Hz
It should be also not very complicated and need a few external components.
Best wishes;
Jan