Neil, I just found your Simulation Schematic from 9/26 for converting the final Big Talker stage for use at 170 kHz. How did I previously miss this entry? I just scrolled through the 4-pages of this link thinking I'd find an entry linking to the simulation, but I couldn't find one.
This is a major step forward in building our long wave transmitter.
See it here
http://part15.us/node/3008
Next step: an oscillator.
So lucky I found this and THANK YOU.
Carl,
Sorry about that. I put it up in another thread so it wouldn't fragment this one diverting it into a design thread. It's OK with me if this happens but I didn't want to do it.
Glad you found it.
Neil
A webpage is now open to document the DEEP VOICE long wave transmitter project.
http://www.kdxradio.com/deepvoice.html
Hey Carl..have you considered moving your site over to Joomla or Wordpress instead of plain old html?
Both make web page authoring ridiculously easy. And you can implement features that html can never do.
Put it this way..if it takes you 5 minutes to construct a simple web page in html..say the new page you just added, in Joomla it would take you 15 seconds. And no fumbling with html either!
Think of it as the warp capable ship compared to the horse drawn carriage.
RFB
I have not done that because I am not aware of the choice. No one has ever explained to me what those other sites are. I've heard of Word Press but have never known what it is. Joomla is a whole new name.
Right now I'm going to cling to what I know, but there will be a change right away..... I'm going to start edging toward those other methods.
Thank you for the street education. Junior College is over priced.
Take a look at the Joomla application. It is much easier than the Wordpress, but they are similar. I use Joomla on my sites and is why it has the very complex and sophisticated layout and appearance, yet the process to create it was..as I said...ridiculously easy.
Let's put it this way...if you can work your way around facebook, this will be even easier to understand and implement.
Free and it is not difficult at all to convert html pages over to it. Plus these types of web sites are far more search engine crawler friendly. Meaning your site will have better chances of climbing the page rankings in search engines.
The best feature I like in Joomla is that you can create different layouts for your site, and all within the same application and choose between them without having to rebuild anything! Imagine trying that with plain html!!!
RFB
ANNOUNCING - THE FIRST VERSION OF THE DEEP VOICE LW TRANSMITTER ON PAPER
http://www.kdxradio.com/deepvoice.html
Now that I have the 1st Draft of the Deep Voice LW transmitter, I am confused about the crystals.
On the project page I specifically list the crystals values that would be required to transmit on the frequencies 162 or 180 kHz, but of thousands of crystals found in catalogs there are no crystals rated for the needed values.
What, then, is necessary to get "on frequency?"
Start with a stardard crystal frequency, easy to obtain and run that through a divide-by counter to obtain the desired frequency.
I used a 24 mHz ocillator and a simple TTL chip to arrive at 1500 kHz.
This advice doesn't fit the problem...
"Start with a standard crystal frequency, easy to obtain and run that through a divide-by counter to obtain the desired frequency."
The circuit under discussion is here...
http://www.nutstreet.net/k0lr/lftx.htm
The target frequencies in our project are 162kHz and 180kHz
Long wave has 9kHz spacing.
The author of this schematic seems to be ultra imprecise in his instructions for actually using standard channels.
Carl, the idea of using a simple divide-by circuit is the concept. The schematic you referenced uses that idea. You just need to find a crystal that would divide down to the desired frequency.
For instance a divide by 16 would need a 2.592 mHz crystal for 162 kHz. For 180 kHz a 2.88 mHz crystal would do. The referenced schematic uses a divide by 32 which starts with a higher frequency crystal.
CRYSTEK CRYSTALS is still in business. You can order the frequency needed from them.
I bought a 24 mHz clock chip (complete oscillator in a postage stamp sized can) for a few bucks from Digi-Key. I used an HD74193 TTL chip to divide 24 mHz down to 1500 kHz.
At the 160 to 190 kHz range a VFO or VCO might be stable enough
I made a list of the crystal values that would divide down at the available output range, i.e., 16, 32, 64, 128, and the crystal frequencies I listed did not seem to be "standard values."
I considered the values listed in the Mouser and Jameco catalogs as "standard," but none of them were right.
Thank you for naming CRYSTEK, I'll give them a try.
Why fuss hunting down specific crystals? Why not put a PLL circuit with an oscillator and generate those fundamentals directly? Save from having to pay for crystals and provides a quick way to change frequencies.
Here is a perfect little PLL kit that I use on many of my TX projects..including one used in my Panaxis FM-10 exciter/transmitter for backup in case the DS8907 chip decides to take a dive, though I have 10 of those suckers on stand by! 😀
This PLL kit has everything on board including the PLL loop filtering and loosely coupled sample path. All it needs is an oscillator, which there is room on the board complete with un-soldered pads in which to permanently install an oscillator circuit.
RFB
Carl, I sent a request for info to Crystek to see what solutions they may offer. I'll let you know if they reply.
As for "standard values", Crystek will grind most any frequency you want. At least that's what they used to do.
The Deep Voice LW Transmitter Project is in its early stages, so with RFB's "P.L.L." suggestion we now have a Second Option for ways of building the prototype. I will add a diagram to the project web page showing both methods.
I will continue on the path of Version No. 1, I like its simplicity, but I may also try Version No. 2 later on.
Others who use these schematics to build their own will appreciate having these two approaches as part of the learning process.
Here is the Deep Voice Project site
http://www.kdxradio.com/deepvoice.html
MORE INFO ON OPTION #1:
X1 : Target Frequency = 162kHz: *16= 2.592mHz; *32= 5.184mHz; *64= 10.368mHz.
Target Frequency = 180kHz: *16= 2.880mHz; *32= 5.760mHz; *64= 11.520mHz.
These numbers show the needed crystal values.