Pyrazo Replication Info

[Macchendra]

More details...

Here are more details on the design. Tubes are definitely going to be tricky, because even with the op amp design I have provided, you will have to ensure that the output of the op amps are set to within specifications for the tubes, in voltage and amperage. Also, with the tubes, the heater circuit has to be of the right voltage and amperage.
The whole timing circuit, now done with the op amps, does not share a common ground with the rest of the circuit. This means that in order for the grid to be more negative than the cathode you have to have some means of making the grid voltage relative to the cathode, like the diodes I have going to the -Vcc of the op amps in the last timer design for the tubes:


All of this really makes the tube approach something fit for only those who are pretty experienced at all of this.

Relays should be able to provide a nice proof of concept and do not involve as much expense, the challenge of the heater circuit, the challenge of side effects from cathode biasing, or the challenge of being precise with the voltage and amperage from the timing signal.

Modern relays are also available in high frequencies and can be very durable.


Here are some more pictures to help people get their heads around the concept.

Including one that breaks down the components of the timing circuit.


One that shows the expected waveforms.


And one that shows the intended operation of the device.


Some links that help with understanding the various components are:

The clipper component:
Clipper (electronics) - Wikipedia, the free encyclopedia

The differential lo-pass filter op amp circuit:
Phase Locked Loops
Operational amplifier applications - Wikipedia, the free encyclopedia
Low-pass filter - Wikipedia, the free encyclopedia

The comparators:
Operational amplifier applications - Wikipedia, the free encyclopedia

The inverting integrator:
Operational amplifier applications - Wikipedia, the free encyclopedia

Where the voltage spike in the secondary comes from:
Ignition coil - Wikipedia, the free encyclopedia


Peace!
-David

[Macchendra]

The link on the Ignition coil sucks...

The link on the Ignition coil sucks...

A better explanation of the voltage spike in the secondary is that when the primary is interrupted mid peak, the voltage in the secondary is proportional to dI/dt, which is theoretically -infinity, but practically much less extreme than that. That voltage spike is shunted back to the antenna in a direction that pulls the signal in.

The two driving forces in the circuit are the signal, and the voltage spike from the secondary.

[Macchendra]

Bounty, reoffer... easy money.

$10,000,000 of the first $50,000,000 of the licensing fees of this device for whoever demonstrates the first working prototype.
And $1,000,000 of the first $50,000,000 of the licensing fees of this device to each of the next 5 distinct individuals that demonstrate a working prototype.

I'll even help build it if anyone is in Plano, TX.

Here are good values for 60 Hz.

R1,R2: 70 Ohm (power resistors)
R3,R4: 220K Ohms
C1: 220 uF
R5,R6,R7,R8: 800 Ohms
C2,C3: 3 uF
R9: 10K Ohm
C4 100 uF

You will need to take it step by step as you assemble it.
Start with making sure the tuner/timer circuit is working with the following steps:
Make sure you are getting proper voltage from your power supply/virtual ground circuit.
Next, run 60Hz from your function generator through the T1 isolation transformer and scope it just to see how it comes out. It should be clean and not shifted.
Then assemble the circuit surrounding the op amp on the far left. This is a simple lo pass filter the out put should be in phase. You can test it with the function generator to see how it responds to changes in frequency.
Next, add the second op amp from the left. You should see a nice clean square wave output from this.
Next add the third op amp from the left. This is an integrator. The square wave should now be a triangle and shifted 90 degrees.
After that, the fourth op amp should make your triangle wave back into a square wave again, but still shifted 90 degrees.
The last set of op amps on the right should then be tested.

When you are done you should have a clean signal to drive whatever switching device you choose: relays, transistors, tubes, etc.

Next, hook up your antenna. You'll want to go through the primary of the isolation transformer and the pulse transformer then to ground without the switches for initial testing. See if the signal you are trying to work with is strong enough to be detected by the op amps. If you need to boost the signal, you can vary the ratio of R5,R6 to R7,R8. R7 and R8 are the only values that have to be paired with the capacitors C2 and C3 to get the frequency you want. You'll want R7=R8 and C2=C3, and you will also want frequency cutoff to be around 65 Hz. You can use an online lo pass filter calculator to experiment with the values while keeping the frequency cutoff the same. The gain of the lo pass filter will be about R7/R5 (which should be R8/R6), and you might want to tweak R5,R6 to get the gain you want.

Once you are getting a clean signal through the whole rig, you can then throw the switches into the mix. The switches should distort the signal with the spike mid peak, and the signal should grow.

Peace!
-David

[Macchendra]

Meh?

Meh? Well, I will have the money to do it shortly. Thanks for your time and interest.

[ewizard]

Still around Macchendra? Any luck on this fascinating circuit?