UK Vintage Radio Repair and Restoration Discussion Forum - View Single Post - Ferrite rod antenna and RF amp for Valve radios

John_BS · 8th Oct 2019, 9:10 pm

If your LW coil inductance is as you stated, it only takes about 5pF self-capacitance to resonate at about 1MHz. So you have a second fixed-tuned resonator coupled to the MF coil via the rod. A kind of crude second-order filter. Is your LW coil at the other end of the rod from the MW?

8th Oct 2019, 9:10 pm	#18
John_BS Octode Join Date: Dec 2008 Location: Wincanton, Somerset, UK. Posts: 1,780	Re: Ferrite rod antenna and RF amp for Valve radios If your LW coil inductance is as you stated, it only takes about 5pF self-capacitance to resonate at about 1MHz. So you have a second fixed-tuned resonator coupled to the MF coil via the rod. A kind of crude second-order filter. Is your LW coil at the other end of the rod from the MW?