Dear All. I am having problems with the choice of material for the output network of the 475kHz Valve TX . The network is an L – C – L, ‘T’ network with an input impedance of
Hi Ken, I would first transform to 50 Ohm using a BIG ferrite core and then use iron powder cores to build the LPF. T-200-2 types work fine on MF for decent power levels :-) 73, Stefan Am 17.10.2015
PS: For the RF transformers i often use N30 ferrite material with good results. An AL of 4000 nH or above is a good choice. If you want to use Amidon ferrite cores, use type 77 material (available on
Hi Stfan. I have been looking at the 77 type material, but waiting for other group members opinion. 73 Ken From: [email protected] [mailto:[email protected]] On Beha
I would recommend type 77, I use an FT240-77 up to 400W and it's scarcely warm. The price is good compared to the Ferroxcube alternatives. Hugh, M0DSZ On 17/10/2015 17:11, Ken wrote: Hi Stfan. I have
Hello Ken, For transformers I have used Amidon -77 ferrite material successfully on 136 and 472 kHz. Same goes for Ferroxcube 3F3 ferrite material. For inductors in filters or chokes the Amidon -2 ir
Hi, I took a FT-240-77 in my large PA a while ago. The primary winding can be seen here: https://dl.dropboxusercontent.com/u/19882028/MF/20130713_002528.jpg 47 turns were fine to switch a 475 kHz (ne
Old LOPT fm TV'S work well 3C85 cores --make sure there is no gap between the two halves when re assembled No cost ie scrap value G3kev Sent from my iPhone
