[NLRS] RTL2832 DVT-B dongle on HF

[Doug Reed]

Did I mention this already?
Progress is being made to use a modified or damaged dongle as a HF SDR
receiver. It turns out the RTL2832 can be programmed to use an "IF 
frequency" anywhere in the 0-30MHz range, just by telling it what 
frequency to use. The hardware mod is to disconnect the E4000 receiver 
and feed the antenna directly into the pin 1 input of the RTL2832 chip. 
People are doing this when they have a dongle with a bad or damaged RX 
E4000 chip.

The second email was interesting too. It suggests that a different model 
dongle should cover from below the 6M band and up to (maybe) 910MHz. Of 
course any of them will be good enough to use as a SDR display for the 
2M band with a transverter. As long as I don't try to decode audio, the 
waterfall works fine on my little netbook, even at the default 2Mbps 
sample rate.

The slowest sample rate I see is about 250KHz so it shows +-125KHz of 
the band around a center frequency in the 2M band.... I haven't played 
with these in any significant way so I don't know what problems might be 
encountered. And it must be remembered the dynamic range of the RX is 
less than 50dB so it doesn't make a very effective spectrum analyzer if 
you need to look at the skirts of a filter or duplexer.

73, Doug Reed, N0NAS.

SDRSharp at yahoogroups.co.uk wrote:
> 3.1. Re: direct sampling mod Posted by: "p49k"n1kk at netzero.net  p49k
> Date: Fri Aug 3, 2012 3:06 pm
>
> I just tried this out.   I did the hardware pin 1 mod and used the
> dll file from Bob.   Considering I am feeding my inverted V straight
> in I am amazed at what I am hearing.  I was just listening to ARRL
> code practice on 3582KHz along with a local LSB net on 3810KHz.  I
> see lots of stations.  I think with some front end filtering this
> could be pretty cool. Listening to a group right now on 3995KHz LSB
> very easy to tune in. I needed to use a -454,000 shift for correct
> freq display.
>
> Ken N1KK
------------
> 3.2. Re: SDR# with RTL2832 E4000 dongle.... Posted by: "eheh_ehvk"
> prmarcos at gmx.net eheh_ehvk Date: Thu Aug 2, 2012 2:29 pm
>
> Hi Roley, Joanne,
>
> Same experience here with E4000 PLL locking from 51.5 MHz up, so with
> sufficient sampling rate you could JUST tune down to 50 MHz.
>
> Very interested in VHFI and 6m/50MHz myself, I also have an FC0012
> based stick (terratec) and an FC0013 (supposed to be EzCap E4000)
> that both tune from 37 MHz to about 910 MHz. Might be a very good
> alternative for you as well.
>
> BR, Marc