Feel free to add information to the wiki or make edits as needed. Please respect the work of others by adding your own content rather than editing or removing someone else's content unless doing things like updating URL's etc.?
|
Re: DDS VFO!
I do have 3 NC-40 boards. and one NorCal Sierra board with 4 band modules.
There was a time the Heathkit HW-7 and HW-8 were popular. They are direct
conversion.
I'm thinking about building a clone
By
Bob Macklin <macklinbob@...>
·
#56
·
|
|
Re: DDS VFO!
BTW:
The NRR group operates 40M CW in the old Novice segment. Or what's left of it. 7100:7125, 7125:7150 is Extra territory.
SKCC also has CW activity in the 7100:7125 segment.
Bob
By
Bob Macklin <macklinbob@...>
·
#55
·
|
|
Re: DDS VFO!
The schematic is on page 9.
Lots of guys on here probably have extra NC-40 boards, you could use one of those,
and later add the IF and make a better receiver...
73,
Gary
WB6OGD
By
wb6ogd
·
#54
·
|
|
Re: DDS VFO!
Just found one on eBay:
https://www.ebay.com/itm/MRX-40M-RECEIVER-KIT-QRP/283613875523?hash=item4208b44d43:g:nI4AAOSwq~9db-MY
Ordered it. Will convert it to a DDS VFO.
I am sitting here with an
By
Bob Macklin <macklinbob@...>
·
#53
·
|
|
Re: DDS VFO!
Does anyone make a PCB for a 40M DC receiver. Maybe clone the old Ramsey
receiver?
The PCB pattern is in the published manual. But not the schematic.
Maybe I should reverse engineer the Ramsey Rx
By
Bob Macklin <macklinbob@...>
·
#52
·
|
|
Re: DDS VFO!
Adding a prescaler does not reduce the accuracy if you extend the sample
time.
You could have two sample times. FAST for quick look and SLOW for accuracy.
Bob Macklin
K5MYJ
Seattle, Wa.
"Real
By
Bob Macklin <macklinbob@...>
·
#51
·
|
|
Re: DDS VFO!
I built my NC-40A about a year ago. One of the nice things about the rig
is its VFO. I set mine up for 7015 to 7047 kHz. A bit limited in that it
doesn't cover the activity around 7112 to 7123, but
By
Nick Kennedy
·
#50
·
|
|
Re: DDS VFO!
What is wrong with the old novice band?? I frequently listen there.
Because it is there...errr because I can.
There was some comment that a DDS vfo has a pretty low upper frequency but the AD985x
By
Jim Pruitt WA7DUY
·
#49
·
|
|
Re: Group Introduction: If you're going to post on the group, reply here!
Hi,
I don¡¯t post much (or ever!) but I do lurk daily and usually learn something in the process. Thanks for carrying the flag!
Newt
N4EWT
By
Newt N4EWT
·
#48
·
|
|
Re: DDS VFO!
Hi
Some but not all Arduinos can count up to 6,4 MHz, i.e. 40% of clock frequency. Empiric data shows a bit higher, ~43%. The Arduino Zero can count up to 90 MHz e.g. as implemented in the RFzero:
By
Bo, OZ2M
·
#47
·
|
|
Re: DDS VFO!
You can put a divide by 10 in front of the 328 counter input and go higher in frequency if you want.
Bob Macklin
K5MYJ
Seattle, Wa.
"Real Radios Glow In The Dark"
By
Bob Macklin <macklinbob@...>
·
#46
·
|
|
Re: DDS VFO!
Arduinos can count to 6.4MHz so Digital
dial for a NC-40 is a piece of cake.
Resolution to the Hz, accuracy depends on
calibration and temp/voltage variation.
You COULD GPS discipline it for
By
wb6ogd
·
#45
·
|
|
Re: DDS VFO!
How about digital tuning accuracy?
I have several GOOD HF receivers with analog tuning and they do not have precision readouts. Only good to about 25KHz.
There was a digital display for the NorCal
By
Bob Macklin <macklinbob@...>
·
#44
·
|
|
Re: DDS VFO!
And...
Though I don't see the need to add a DDS VFO to a NC-40, my own NC-40 does have an Arduino add-on.
It functions as:
AFA? audio frequency annunciator (in CW)
Iambic keyer
Keyboard CW sender
CW
By
wb6ogd
·
#43
·
|
|
Re: DDS VFO!
Ok guys.? Sometimes a project is worth doing just because its there!
An Si5351 VFO is a really good project just to have around so GO DO IT!
If you need any help with Arduino coding let me
By
wb6ogd
·
#42
·
|
|
Re: Group Introduction: If you're going to post on the group, reply here!
That is my hope as well!
--
Ryan Flowers W7RLF
https://miscdotgeek.com
By
Ryan Flowers
·
#41
·
|
|
Re: Group Introduction: If you're going to post on the group, reply here!
Thanks for creating this new space. I learned a lot from the old QRP-tech group and I am hoping this learning will continue here.
Karl Heinz - K5KHK
By
Karl Heinz Kremer - K5KHK
·
#40
·
|
|
Re: DDS VFO!
BTW:
Above 7125 is PHONE space. No one looks for CW between 7125 and 7300.
The only time I hear phone activity on 40M is during contests.
Bob Macklin
K5MYJ
Seattle, Wa.
"Real Radios Glow In The
By
Bob Macklin <macklinbob@...>
·
#39
·
|
|
Re: DDS VFO!
I want the DDS so I can have CAT control.
Currently I use CW Get and CW Type for CW operation.
I'm 85 years old and my hands don't work very well anymore.
They are not the only things that don't
By
Bob Macklin <macklinbob@...>
·
#38
·
|
|
Re: DDS VFO!
Hi Allison,
That is an acceptable price to pay, for me at least!
By
Michael N6MST
·
#37
·
|