DIY FM Tuner challenge

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I just clicked my way through a block diagram (which I can't find again) at TI.COM, and ordered these recommended & available parts:

ADS807E, MSP430F1101AIDW, PCM1716E, THS3001CD, TMS320VC5402GGU100, TPS5602IDBT, TRF6900APT

I don't know which are actually appropriate (or much else; hopin' you can tell me). The price sure is right. TI ships 'em overnight, free (US). With a few more miscellaneous parts, and a small enclosure...

Crossovers & Amps abound online (former is complete; latter in-progress). A decent FM tuner design would be a welcome step toward a completely DIYed system.

Thanks,
Steve
 
i don't think so, steve

The referenced site lists the reciever component as:

'The TRF6900A single-chip solution is an integrated circuit intended for use as a low cost FSK transceiver to establish a frequency-agile, half-duplex, bidirectional RF link.'

Looks like a design for a handheld radio. Might work for a home broadcast solution but I don't think it will work for regular fm radio reception.

Happy New Year
:drink:
Dave
 
To Another Middle Aged Slacker.........

Hi Steve, I am not able to get onto the website concerned at present for some reason.
From memory the main chip is SMD, and there are a handfull of specialised components like ceramic filters required (probably available from Farnell or RS Components), but it ought to be do-able.
The completed item I have seen (and heard) has station presets also.
I think that it also has RDS capability, but this may require extra support circuitry.
Sorry, thats all I know for now and i'll get back when I have more info.

Eric.
 
If anyone successfuly build a diy FM reciever, especially of audiophile quality, I hope the post all the details somewhere. In fact they could, they could probably sell a PCB + construction guide for enough to pay for their project. DIY FM is something quiet a few people are interested in but the difficulty remains (so far) beyond the skills of most of us.
 
This guy seems to have access to a Philips radio module (bottom-right on the picture)

uCgpsBb.jpg


Full page here, but my german's too poor, and automatic translation gives funny results, so all I can do is blind clicking ;) Any German here to help us ?
 
FM reception in a car is a special case.
By that I mean that the environment is subject to different conditions than a domestic one.
Petrol (gasoline) vehicles, and diesels to a lesser extent, produce a lot of impulse interference. FM detection and limiting fails in the presence of such large amplitude pulses, causing audio interference.
Car radio and chip manufacturers have got over this with some clever circuitry. Sometimes this involves delays and noise and signal"gating".
Another problem is "fade". This is not the same varying received signal strength that occurs due to atmospherics. When driving in town, there are constant refelections. Mostly there is no line-of-sight path from the transmitter. As the car moves, the reflections add and subtract, causing the signal level to fluctuate wildly, often cancelling momentarily.
The manufacturers also have methods to reduce the unpleasantness of this effect. These range from fast AGC to variable IF bandwidth and stereo blend circuits.
It's been a while since I was into automotive chips, and things have probably moved a lot further in the meantime.
Such sophistications are what makes a Blaupunkt (Eg) a mile better than the base model that was fitted in my Nissan.

The bottom line is that a good receiver system for home won't be the best for car use.
 
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