Hi Garey:
Yes points well taken. In my case, I did this before the ensemble was
available. Had I had that availability, I would have chosen to go that
way as well.
It does work well tho. I didn't see much of an issue at all with the
limitation from the preselector. In practice, I was simply looking at
perhaps +/- 5-10 KHz when in CW sprint mode. I liked the filtering so
well in the SDR, that I worked a couple of CW sprints using the output
only from the SDR instead of the Drake mother Rx. Issues there were
the delay and lack of a good mute method.
Overall, it was a simple thing, no harm done to the Drake, a good
learning exercise, but the lack of tracking ability for the center
frequency really limits the real Panadapter concept.
Mine was in an external, diecast shield box, so I did not have any
issues with radiation from the SDR.
All over again, would just build the Ensemble like you suggest.
Fun tho.
Curt
KU8L
On 2/9/2012 9:44 AM, Garey Barrell wrote:
Curt -
I guess I'm missing the objective here. I have several SoftRocks,
Ensemble, etc., and the biggest 'feature' they offer is the ability to
see large chunks ( 48, 96 or 192 kHz ) at a time. If you tap off in
front of the roofing filter, 5.645 MHz 1st IF, all you are gaining is
an RF stage and mechanically tuned LO. Your widest 'window' is 20 kHz
because of the PreSelector bandwidth.
It makes sense with one of the modern radios with octave filtering in
the front end so you CAN see the entire 48 or 96 kHz capability of the
SR. I just can't see the advantage of putting a state-of-the-art,
computer controlled receiver BEHIND a mechanically tuned, 50 year old
front end.
I guess I just don't understand the objective unless it's just all the
IF bandwidths, etc. Seems to me a much better option is to just go
with the Ensemble and get 1- 30 MHz continuous coverage, tunable from
the PowerSDR or other screen. I can't hear anything on any of the
Drakes that I can't hear on the Ensemble, being limited by
'atmospherics' rather than noise figure.
The Ensemble in it's little QSL sized case just sits there and
receives everything, all under the computer control. ??????
73, Garey - K4OAH
Glen Allen, VA
Drake 2-B, 2-C/2-NT, 4-A, 4-B, C-Line
and TR-4/C Service Supplement CDs
<www.k4oah.com>
Curt wrote:
Hi Carey:
I did exactly that a few years ago with my a version. It works
really well and is a excellent way to get involved with SDR, the
Software, and get a panadapter along the way.
You need to get the proper IF version softrock. The SDR needs to be
tapped off of the 1st IF before the filtering. The SDR needs to be
able to see unfiltered RF at the IF frequency.
You need as good a Soundcard as you can afford. The Delta44 is one
of the ones widely used.
The connection to the main Rx is a bit touchy. I used a gimmick and
a small cap but that is less than ideal. Clifton Labs offers a
isolator on a small board that is the real answer.
The Softrock for the IF will be different. The coils are different
as is the crystal. Tony Parks was good about answering questions and
providing info. He can probaly supply the stuff you need to convert
the 40M kit since I don't think the IF kit currently being done
includes the Drake IF freq.
Hope this helps
Curt
KU8L
On 2/8/2012 10:34 PM, Carey Lockhart, KC5GTT wrote:
Hello Gang,
i have a 13 tube r4a i would like to set up on powersdr or another
sdr app. is there a website or can someone point me in the right
direction to what i need to do. i do have so 40m softrock and a flex
1500. either should d the job i would think.
Thanks
Carey, kc5gtt
_______________________________________________
Drakelist mailing list
Drakelist@zerobeat.net
http://mailman.zerobeat.net/mailman/listinfo/drakelist