Greetings, I am having a difficult time finding verification if I am interpreting a schematic correctly. Specifically, it is a schematic by N1AL (Alan Bloom) for "A Modern Grid Dip Oscillator" in the May 2003 edition of QST. http://www.qsl.net/k8mcr/downloads/Modern_GDO.pdf
Q1,Q2 & Q3 are MPF102 N-Channel JFETs. I am using the SMD version, MMBF102 as I have more to spare than the TO-92 MPF102's.
My confusion is is the connection of Q1 & Q2 -
I cannot seem to find a good representative image to help me decipher a source coupled pair like this. If my current interpretation of the schematic is correct, the drains of the two JFETs in this oscillator are coupled.
If I have not made my question too confusing, can someone please take a moment to help clarify my confusion. Would he MPF102's in the form of a source coupled pair forming an oscillator have the drains connected, or am I misunderstanding the mirrored JFET symbol (with gate on right side, does D & S switch locations)?
Thank you so much for your time and if i need to upload a clip of the schematic and am capable of doing so with my low post count, I certainly will.
Thanks again for your time.
-evile
Q1,Q2 & Q3 are MPF102 N-Channel JFETs. I am using the SMD version, MMBF102 as I have more to spare than the TO-92 MPF102's.
My confusion is is the connection of Q1 & Q2 -
Q2 is a mirrored version of the schematic symbol for an N-Chan JFET (Q1). I recognize the layout of the JFET with the gate on the left side, the drain on bottom and the source on top. However, in my mind when it is mirrored and the gate is now on the right side of the schematic symbol, it's drain and source remain oriented the same as the other symbol (drain on bottom, source on top)."A pair of source-
coupled N-channel JFETs (Q1 and Q2) form the oscillator
portion of the circuit."
I cannot seem to find a good representative image to help me decipher a source coupled pair like this. If my current interpretation of the schematic is correct, the drains of the two JFETs in this oscillator are coupled.
If I have not made my question too confusing, can someone please take a moment to help clarify my confusion. Would he MPF102's in the form of a source coupled pair forming an oscillator have the drains connected, or am I misunderstanding the mirrored JFET symbol (with gate on right side, does D & S switch locations)?
Thank you so much for your time and if i need to upload a clip of the schematic and am capable of doing so with my low post count, I certainly will.
Thanks again for your time.
-evile