View Single Post
Old 22nd Dec 2018, 12:10 pm   #43
Neil Purling
Nonode
 
Join Date: Jul 2005
Location: Hull, East Yorkshire, UK.
Posts: 2,082
Default Re: More Chinese AM radio kits

Thank you for moving the posts.

Back to the KX168: This is the last of the four I bought.
I discovered on assembly exactly as specified in the diagram that the audio stage has a feint hiss.
Sitting the PCB on top of a coil that was being injected with a 455Khz signal gave me a 1Khz tone from the speaker that I could peak up with B1 & B2.
I have no evidence that the local oscillator is running. It appears that I have made a mistake in wiring the coil. I will let you know if correcting it makes any difference
The wires are coloured red, blue & plain. The plain wire is the top end of the long winding. The red wire is connected to the negative track. Finally: The blue wire goes to the base of BG1 via C2. That blue wire is the connection between the two sections of L1.
Neil Purling is offline