I got the boards for my third board layout.? So far batting a thousand.
Did get scared when I built the audio section first and wasn't getting
anything out but a click when I probed the input.
Build the mixer and didn't hear anything.? So disconnected everything
and turned the board over.? Pin 5 on the LM386 was not soldered. :-(
That did the trick.
In chapter 1 of EMRFD there is a DC receiver and it is just like all
the rest that you see.? Very simple and not that many parts.
I like the Dave Richards, AA7EE, video with his Manhattan build.
I had a couple of questions, so I laid out a board that would allow
me to experiment.? Here is the first pass, not ready for prime time
as I used the standard library and the holes need to be resized.
I thought I'd add the LED and the bass boost for experimentation
for the next rev.? This the board that went to Germany and back
for a vacation.
All the caps with 0.1" spacing are for the 1,000 100nF caps that I
got off the boat last year.? Decided I need to use some of them.
I plan on adding the 0.1" and 0.2" spacing for the same cap to
allow use of either size.
as an example.? Do your search and order in pricing to get the
best deal.? That is if you think you need a couple lifetime supplies
of the critters.
On the board layout, the C2, C3, C5, C6, C7 and C8 were to allow
different configurations on the low pass filter and the coupling
for balanced and unbalanced.? I settled on the balanced 3K impedance
for both the NE602 on the left and the LM386 on the right.
With a 4.0MHz crystal resonator and an MV1662 I got a tuning range
from 4.000MHz down to 3.917MHz.? Heard some SSB signals.
With 4.0MHz HC-49U crystal, only got 4.000MHz down to 3.997MHz.
The Y1 three pin machined socket allows me to plug-n-play resonators
and crystals.? Did 5.000MHz and got WWV.? Did 7.030MHz and heard
some CW.? Did 10.000MHz and got the loud WWV.? Did 10.116MHz
and didn't hear any signals, but never know at 5pm local.
This all without the band pass filter (BPF) to the left of the NE602.
The unlabeled four pads to the left of C20 are for the toroid.
Also an area to experiment with BPFs.
Next pass is to add RF amp for a 10.000MHz version like KD1JV did
for calibration of frequency counters.? With audio display on computer
you can get homed in within a fraction of a Hz to 10.000MHz.
I'll do the docs, do the video and put it on my web page.? Don't think
there is going to be enough interest to make it a formal project for
this group.? You've got enough as it is.
I'll give away some boards, but I'm not getting any feedback from
boards sent out previously.? You guys hoarding them?? :-)
Send me email offline, please.? First 10 get a board.? Holes too small
for connectors.? I'll have the docs before you get the board.
FYI
chuck, k7qo, PCBs Gone Wild
OH.? Second board was for the Colpitts with the DJ3KK counter on it.
Both the DC receiver and the second board are 100mm x 50mm in
size.
