Hi!
2011/5/29 Harald Welte laforge@gnumonks.org:
Hi!
For those interested, I've taken apart the case and did some investigation how the FCDP hardware architecture looks like.
The results are available at http://tetra.osmocom.org/trac/wiki/Funcube_Dongle
That's quite interesting as the E4000 seems to handle all the analog stuff without external LNA, etc. Simplifies things a lot.
It seems the silicon tuner actually is intended for DVB-T, thus the bandwidth it can down-convert is _much_ higher. However, the audio codec that they use can only do 96kHz.
That's actually really sad. I wish they had used something with higher ADC rate. But it seems like even high-end audio codecs never get you beyond 196/216 kHz - still insufficient for e.g. GSM.
I wasn't able to find the output bandwidth of the E4000 somewhere on the website. Do you have an idea of the bw? Still, gluing a faster dual-ADC plus hi-speed USB IF to the tuner shouldn't be that much of a problem.
It seems though, the E4000 can only be obtained from Elonics. No luck with digikey, R+S, farnell... Maybe we should try to ask Elonics if they'd be willing to provide some samples+datasheet and the DVB-T reference design. If we somehow could put an open design together, I guess we could find someone to build+sell larger quantities.
I really would be interested in such a dongle w/ faster ADCs. What do you think?
Regards,
Benedikt / hunz