Re: New style FSL Part 2


Andy ZL3AG
 

Basically the same as the G Maynard "Spiral Loop with Q Multiplier" from the 1980's, with ferrites added. :^)

His design was balanced, with a centre tap half way up the windings which went to the ground of the capacitor, with two gangs of the capacitor used - one going to the top exit winding and the other to the bottom.

Q multiplier on that main balanced loop winding and then a MUCH SMALLER DIAMETER pick up turn further in towards the centre of the antenna, to reduce dampening. Made for very sharp tuning - I could peak it on one or other sideband of a station, and you could hear the peak track across the audio bandwidth of the station as you tuned the loop.

On 13/12/19 3:02 pm, Dean wayman wrote:
Hi Bill;
Nope the nulls are very sharp, in fact much sharper than my regularly wound FSL's . as far as a distorted pattern I haven't seen that . These loops have a figure -of -eight pattern ,gain is in line with  the loop and nulls to the side . So in other words the front edge of the loop points directly at the station being received .
I don't know if i can explain this part ? ...but  the Flux which the loop generates is concentrated on the inside and outside edge of the windings not on the ferrite  itself . I found a very detailed article on this but have lost it . look around the net maybe it will pop up ?
Dean W.

Join main@UltralightDX.groups.io to automatically receive all group messages.