[Amps] construct ferrite "line isolator"

[Jim Thomson]

A 6 mix iron powder is good for 6-10M, I use it as the L in the input pi
>>network for amps. If it works for you for HF RFI than thats good, Id guess
>>it wasnt too severe and just a little bit of impedance did the job.
>
> REPLY:
>
> The Palomar data sheet says #6 is good for 2-30 MHz.
>
> http://www.palomar-engineers.com/Iron_Powder/iron_powder.html
>
> Where did your information come from? Perhaps different manufacturers use
> the same number for different mixes?
>
> 73, Bill W6WRT

Straight from the Micrometals spec sheets and then some testing. There is a 
huge difference between using it in a SS HF VFO and with actual power with 
much larger wire which limits the low frequency. The 6 and now the 7 mix is 
very stable compared to the 2 mix and popular with the QRP crowd. OTOH the 2 
mix is the "standard" in 1.8-30 MHz 4:1 baluns....far from perfect but 
useable.

Palomar makes nothing besides CB amps and little accessories, they buy from 
Micrometals the same as I do.

Carl
KM1H

##  we are talking apples and oranges between  ferrite + iron powder ! 

##  sure, 2 mix iron metal will work for toroid cores for  160/80m tank coils
in a linear..and that's abt it.      Wind a bunch of turns on 2 mix, and ur lucky to
get 8-12 uh.... which is plenty of uh  for a low freq tank coil..but hardly enough
for rfi suppression.   4 x wraps of RG-393  through 4 x 2.4" OD, type 31
torroids yields aprx 132 uh.   17 x 1" diam x 1" long  type 77 beads slid over
RG-393  yields 63 uh....[and 38 uh if type 43 used].

## powdered iron is abt the most useless thing there is for RFI suppression...unless
you use a case load of it. 

Jim   VE7RF