[minima] Re: BSS-1 Transceiver Project
- From: "Jerry Gaffke" <dmarc-noreply@xxxxxxxxxxxxx> (Redacted sender "jgaffke@xxxxxxxxx" for DMARC)
- To: "minima@xxxxxxxxxxxxx" <minima@xxxxxxxxxxxxx>
- Date: Mon, 12 Jan 2015 06:42:20 +0000 (UTC)
Ashhar,
Looking forward to hearing more about both, but watching videos will have to
wait till I'm on a better internet connection. Can you point me to a
description or schematics of each?
> the dds has spurs, in addition to spurs, getting harmonics free signal is
> impossible.
So improving the low pass filter at the output of the DDS is not sufficient to
get rid of the harmonics?
> in order to beat the spurs issue, i used an Si570. the vhf output is
> hetrodyned to hf
So you replaced the DDS with an Si570? If so, you would need a different
lowpass filter for each octave. Not clear what this vhf output is.
As I mentioned here a few weeks ago, DDS spurs might be removed by driving the
DDS refclk from a SiLabs part at an integer multiple of the DDS target
frequency. An original thought, though I'm sure it's been done.
Anyways, all the talk here about evaluating mixers and filters and if amps has
me thinking I should figure out VNA's.The N2PK uses a slow 24 bit ADC, he says
it gives better resolution than the log detectors.
Jerry, KE7ER
On Sunday, January 11, 2015 6:11 PM, "farhanbox@xxxxxxxxx"
<farhanbox@xxxxxxxxx> wrote:
i did make this kind of a thing a few years ago. here is the video :
Other related posts:
