I agree.......................with a 3-wire power cord, MW reception is
improved. I niticed the same characteristic with my Palstar R30. The audio
does sound quite good.
On another note, I did finish the RF Generator design. This is a DDS based
unit that covers from 10kHz to 30MHz, in 1kHz steps. Actually, the final
unit will probably tune in finer steps, and it could cover up to 60MHz with
this chip (AD9851) . Modulation range will be from 0 to 100%, with a 1kHz
tone. Tuning method? Rotary shaft encoder, along with keypad entry.
Projected price? I am shooting for the 350 to 400 dollar range.
I characterized the prototype over the weekend. 2nd, 3rd, and 4th harmonics
measured at -25dBc, -35dBc, and -45dBc respectively. I didn't have the
equipment to characterize phase noise, but with this scheme, as used on my
DDS, phase noise measured at -124dBc @ 7kHz offset, using an Epson SG636
packaged 30MHz oscillator as a 30MHz reference.
Frequency error @ 30MHz was only 3Hz. Stay tuned for further developments.
As far at the MW receiver design, all of the RF design is
completed....................I am only waiting for the software person to be
freed up; when this happens, we can move forward.
Right now, I am learning how to use Protel DXP. This is the program that I
will be entering the final design information into.
A nice program............it does PSpice simulations, microstrip
calculations, etc, in addition to the normal schematic capture and board
layout functions.
Pete
"Brian Denley" wrote in message
news:d6Jcc.200431$1p.2281442@attbi_s54...
Pete KE9OA wrote:
Hi folks,
I decided to check out my SW8 a little bit more. I
measured the wall wart voltage, and it measured 9.6VDC, so it seemed
to be within limits. Just for the heck of it, I checked the ripple
voltage with a scope. 4.6V p-p of ripple!
.
.
Still not quite as sensitive as my other receivers, but not bad. MDS
is now down below .1uV, which is pretty ok.
Pete
Good info Pete. I expected you to get more out of the receiver. My SW8
was
a very good radio with a nice mellow sound. It was my favorite receiver
for
program listening. The filters do seem a little wider than advertised and
that may be responsible for the nice sound.
--
Brian Denley
http://home.comcast.net/~b.denley/index.html