Testing of USB FM Radio from Silicon Laboratories
By Courtesy of Silicon Laboratoires and their Hungarian Distributor HT EUREP Kft. Budapest, I was a possibilty to test this module.
I tested it from the viewpoint of using in carputers.
The results:
The module:
It’s a simple USB key format module with a cca 70 cm long wire, as the aerial.
The unit is a possibility of use of the SLAB chip FM Radio Tuner Si4701 and USB enabled microcontroller ( C8051F321).
This two chips are mounted on a little pcb panel with a few additional parts. This is a very simple work, (or the chips can get everithing)
The installation of module:
It’s very easy. The unit is absolutelly plug and play, under windows xp. After a few seconds recogise as a composite USB unit, and after this as an FM radio. After 5-8 seconds ready to work, wthout any requst of install.
The software:
It’s a very simple but good working software. Can download from this link:
http://www.silabs.com/public/documen...n/USBRadio.exe
It was developed in C++ and visual studio 6.0 and the source code is available:
http://www.silabs.com/public/documen...en/AN264SW.zip
All of codes, skin parts, and headers can download from here. This is a good possibility for the further developing. The users guide link is:
http://www.silabs.com/public/documen...B-Radio-RD.pdf
The downloaded part an exe file only. Not any installation required, click on, and working.
The string and closing speed is very impressive! Starting and closing immediatelly. This is a good thing for embedding any frontend software for Car PC-s.
After starting the program recognize the radio unit automatically, and working immediatelly.
The display illuminate the mono-stereo mode, Signal strenght(it’s important) the frequency, and RDS indentification,
The buttons are: preste buttons (12pcs), great work to programming, if You hold down, store the actual frequ. As in a car FM radio. Step up, step down, seeking, and intro buttons. + a volume level ctr.
This is a very usable and simple prog.
But a few words: the working preset number not signed anywhere. The RDS ID is in 4 digit only. For further development can increase this to at least 8-10digits.
Working of the FM radio:
This product not supported the RDS service. The radio wth RDS will comes frist weeks of 2006 (SILAB info)
Generally the work of unit is unproblematic, I not find any problems within 3 days continuous action.
The reception. This is a very important part of using USB radio modules.
With a desktop computer worked very good, but here is a very much troublesome parts, working motors….etc.
The place was a very bad conditioned place of receiving, but working good, without any request of positioning aerial.
In car can test with a notebook, without any additonal aerial. The wire was hang out on the window. But works good.
The reception depends from the quality of unit( I think it’s no prblem) the quality of coverage, and the aerial.
The SILAB FM radio working very good in car, but for further use: Must find a good place in car, the outermost distance from the Car pc. And for the secure work I think must build a possibilty of car aerial connction.
The price: The informational price of the unit is $5 !!!!!! after 5th asking too!(in case of buying minimum 75 pcs)
This is a very competitve price. With this knowledge this unit should be an base part of building Car PC-s.
Nevertheless this is a very simple, and very good quality soluton of this task.
I commend for everybody to try and use.
Laz