- #1
perplexabot
Gold Member
- 329
- 5
Hey all. So I am now trying to work on IF amps for a superhet AM receiver (medium wave) and found the following figure in the ARRL handbook:
I have a couple of questions regarding these schematics.
First and most importantly, do these work for IF signals (of 455KHz with BW of 18KHz)?
Assuming the answer to the above is "Yes," these questions follow:
For medium wave can I disregard VHF and UHF parasitics and go for the simplest schematic (schematic A)?
Why is it that the collector is not connected to the center tap (but somewhere below/above)?
What is the variable capacitor's job?
Why are the inductors (of the output transformer) not the same size? Does this just mean that the transformer has a ratio of x:1?
Why is there a capacitor connected to Vcc? Is it to prevent the signal from going to the source, Vcc?
I am sorry for the long list of questions but I have tried to search for IF amps and this is the simplest of the circuits that I could find, yet I am not able to understand some of it. Thank you for reading.
EDIT: Thank you for the title rename...
I have a couple of questions regarding these schematics.
First and most importantly, do these work for IF signals (of 455KHz with BW of 18KHz)?
Assuming the answer to the above is "Yes," these questions follow:
For medium wave can I disregard VHF and UHF parasitics and go for the simplest schematic (schematic A)?
Why is it that the collector is not connected to the center tap (but somewhere below/above)?
What is the variable capacitor's job?
Why are the inductors (of the output transformer) not the same size? Does this just mean that the transformer has a ratio of x:1?
Why is there a capacitor connected to Vcc? Is it to prevent the signal from going to the source, Vcc?
I am sorry for the long list of questions but I have tried to search for IF amps and this is the simplest of the circuits that I could find, yet I am not able to understand some of it. Thank you for reading.
EDIT: Thank you for the title rename...
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