regenerative

KeithWalker

Joined Jul 10, 2017
1,154
There is regenerative feedback via C7. R1 adjusts the feedback loop gain.
I wonder if this receiver squawks like the regenerative tube radio I built in the early 50s.
 

KeithWalker

Joined Jul 10, 2017
1,154
Some grid dip meters have a built in amplitude modulator so It can be used as an RF signal generator to troubleshoot receiver circuits.
 

Thread Starter

jafal

Joined Jul 4, 2017
13
Some grid dip meters have a built in amplitude modulator so It can be used as an RF signal generator to troubleshoot receiver circuits.
this is modulated grid dip meter dose the square wave attached to the base of q1 acts as RF signal generator ??? the freq of the above schematic is 295 mhz and the coil of q1 one for resonance and the other is antenna grid.gif
 

Thread Starter

jafal

Joined Jul 4, 2017
13
it is an amplifier for earth science the output band of interest is below 400 Hertz.
The delta t of interest between the 2 FG is the data log of the comparator.
using the Filipiak, Kopycki
no Sir it is 295 mhz receiver and the micro controller generate sound in the speaker due the received code and also generate square wave in hertz to modulate q1 what is the aim to modulate q1 bc548
 

sparky 1

Joined Nov 3, 2018
306
Jafal in a regenerative receiver the self quenching creates a waveform shown in figure 4b
http://www.eix.co.uk/Articles/Radio/Welcome.htm
The oscilloscope will identify if the circuit is regenerative.
As I said before the delta t is the aim it derived from comparator so it compares 10 Hz.
The study was completed and published in 1999.
Did you receive CW ? What did it say ?
 
Last edited:

Thread Starter

jafal

Joined Jul 4, 2017
13
Jafal in a regenerative receiver the self quenching creates a waveform shown in figure 4b
http://www.eix.co.uk/Articles/Radio/Welcome.htm
The oscilloscope will identify if the circuit is regenerative.
As I said before the delta t is derived from comparator so it compares 10 Hz.
The study was completed and published in 1999.
Did you receive CW ? What did it say ?
Yes sir you are talking true I am sorry I did not follow with you



positive input. (AIN0) and the negative input (AIN1)

precision analog comparator



As I said before the delta t is derived from comparator
so it compares 10 Hz



Explain this more to me if you please



And what do you mean with>>> the delta t >>>>





it is an amplifier for earth science>>>> give me



some headlight to search the net about this



thanks in advance sir
 

sparky 1

Joined Nov 3, 2018
306
Yes, t=time, delta means the change. so delta t means the change in time.
The chosen bandwidth is 0-400 Hz so 10 works here. The delta t will appear as both the sum and difference. by mixing 10Hz with 258.2kHz
What you do to one side of the equation you must do to the other side so mixing 10 Hz to both sides of the equation; free space and ground.
The first resonant circuit is LC it comes into resonance because 380uH and 1nH, = 258.2 kHz it is where L and C reactances are equal.
Seen on a spectrum analyzer at 247.2 and 269.2 kHz so there is a 1 second delay through the ground compared to free space.
By measuring rate of travel through different materials allows us to cut a coaxial cable to the right length using time domain reflectometer.
The electrical people here will accept TDR and will reject the other method because it fell victim to the free energy cult that made it mystical.
 
Last edited:

Thread Starter

jafal

Joined Jul 4, 2017
13
Yes, t=time, delta means the change. so delta t means the change in time.
The chosen bandwidth is 0-400 Hz so 10 works here. The delta t will appear as both the sum and difference. by mixing 10Hz with 258.2kHz
The first resonant circuit is LC it comes into resonance because 380uH and 1nH, = 258.2 kHz it is where L and C reactances are equal
Seen on a spectrum analyzer at 247.2 and 269.2 kHz so there is a 1 second delay through the ground compared to free space.
thanks a a lot you are very genuases man after your paremission can you help after i do some tests and ask more if i am in need ?

and please exeplane now to me what you said >>>> it is an amplifier for earth science >>>>
 

sparky 1

Joined Nov 3, 2018
306
The GDO grid dip oscillators are great idea. The old GDO were hard to read the frequency on the dial so you needed a frequency counter. Then the antenna analyzer was terrific but was expensive. Now a programmable frequency synthesizer board and an arduino are dirt cheap, it is a great idea from keithwalker for radio enthusiast they want more than just dds. With internet of things interacting with SDR software will make it more useful. I recognise the schematic and the high gain BF transistors will do wide band instrumentation. inductor rangeselect 2 220pF adj caps, 555 audio modulation, simular but application is close range proximity like peaking coils finding nulls.

I don't now too much about earth science, geology and resistivity earth grounding communications earthquakes ect use different sensors. That is a unique field of electronics. It uses amplifiers for instrumentation. Also a friend built something like that in Italy was also instrumentation. he does radio, chemistry and geophysics.
 
Last edited:
Top