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kalee20 · 23rd Apr 2021, 10:07 pm

It's quite true that LW front-ends could cause sideband cutting, I'm right now building a superhet and calculated that I'd want a Q of not much more than 20 on LW.

Having wound myself a nice ferrite rod aerial with 30 strand 0.063mm wire, 3 pies, with a Q of nearly 300, I'm realising I'm going to have to add parallel damping resistors to kill it! At least it's under my control... With an extra gang that I haven't got, I could've made a bandpass front-end and probably got MORE signal into the frequency changer!

23rd Apr 2021, 10:07 pm	#15
kalee20 Dekatron Join Date: Feb 2007 Location: Lynton, N. Devon, UK. Posts: 7,088	Re: Where is the RF amplifier? It's quite true that LW front-ends could cause sideband cutting, I'm right now building a superhet and calculated that I'd want a Q of not much more than 20 on LW. Having wound myself a nice ferrite rod aerial with 30 strand 0.063mm wire, 3 pies, with a Q of nearly 300, I'm realising I'm going to have to add parallel damping resistors to kill it! At least it's under my control... With an extra gang that I haven't got, I could've made a bandpass front-end and probably got MORE signal into the frequency changer!