Help. FISHER GOLDBUG g2

[Arcoman]

either like this: l7- 470 r13 - 30om c14 470nf (470 30 470) ))

[pito]

Build the circuit and test it, paperwork and reality are different.

[Skippy]

I am suspicious about the capacitor values you have for C5 , and especially C3. There seems to be too much low-pass filtering.

[Arcoman]

Ок

[Arcoman]

I am suspicious about the capacitor values you have for C5 , and especially C3. There seems to be too much low-pass filtering.

c3 and c5 are c13 and c14 according to the scheme. In stock. Reduce capacitors? I tried this scheme. Very responsive but noisy, and the capacitors began to make some noise when touched. This may be due to the phase (I will repeat again). I tried what you recommended. Reduce the resistor to 20 ohms and increase the capacitor to 638pf. With a capacitor the sensitivity is less than 4 cm. If you just put a smaller 22 ohm resistor and bring the phase to ferrite, it will work out very well.

[Skippy]

I did say it was a complex amplifier circuit, and making changes would be difficult. Because of the L-C tuned circuit, I said do not change this. Reducing the 27 Ohm resistor is not a bad idea, but it does make it difficult to calculate the new value for the 470 nF capacitor.
Perhaps it is best to leave all the 'lower' feedback components, and keep the changes to C13, C14, and the R10, R11 , 20k / 2k resistors. The resistors need increasing by 25% to 40%, depending on your choice. But the two capacitors need reducing in value, by the same amount, so that every R-C time-constant remains the same. I have not seen a value for either C13 or C14. Their value is not shown on either the schematic in post #7, or the hand-drawn one of the TX850 that I linked to earlier. I suggest you remove the capacitors and measure their value yourself.

[Arcoman]

I did say it was a complex amplifier circuit, and making changes would be difficult. Because of the L-C tuned circuit, I said do not change this. Reducing the 27 Ohm resistor is not a bad idea, but it does make it difficult to calculate the new value for the 470 nF capacitor.
Perhaps it is best to leave all the 'lower' feedback components, and keep the changes to C13, C14, and the R10, R11 , 20k / 2k resistors. The resistors need increasing by 25% to 40%, depending on your choice. But the two capacitors need reducing in value, by the same amount, so that every R-C time-constant remains the same. I have not seen a value for either C13 or C14. Their value is not shown on either the schematic in post #7, or the hand-drawn one of the TX850 that I linked to earlier. I suggest you remove the capacitors and measure their value yourself.

Ок.The circuit in which the device is very stable. 30cm. resistor r63 trimmer 10 kom.

[Arcoman]

I C13, C14, and the R10, R11 , 20k / 2k resistors. The resistors need increasing by 25% to .

How do you like this arrangement?

[Skippy]

I do not like it. You have changed far too many components, by far too much.
If the intention is to increase the gain by 1.3 , then resistor and capacitor values should be changed by 1.3, or 0.77 , or not changed at all. I see you have changed the cap C6 from 470 nF to 100 nF. This shows you are not doing it correctly.

[Arcoman]

I do not like it. You have changed far too many components, by far too much.
If the intention is to increase the gain by 1.3 , then resistor and capacitor values should be changed by 1.3, or 0.77 , or not changed at all. I see you have changed the cap C6 from 470 nF to 100 nF. This shows you are not doing it correctly.

Here is the classic fisher 25 diagram. Here is the graph. phase is practically 0. The device is very stable. We have a camel's hump.I want a deep and stable device. )) very good now. but it could be better. I have not used these 2 versions yet. I still want to hear criticism. but I'll try 100%.

[Artyom]

Arcoman Power the transmitter from a separate 6V stabilizer and the TX current will increase. Please report the results.

[Arcoman]

Arcoman Power the transmitter from a separate 6V stabilizer and the TX current will increase. Please report the results.

For what? the consumption of the device will increase. and I’m doing very well anyway. I'm happy.