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Hi,
While testing my frequency monitoring changes, I've been using FM (into a dummy load and a lightbulb, to reduce my noise on the air).
On 6m/50MHz, it tunes the lightbulb to about 1:1.3 which is OK, but it's using L4 (the first of the toroid ones), and at about 10W (FM), it gets really hot (100C+).
I guess it's one of the following:
1. It's a cheap from Chinese clone, and that toroid is duff.
2. I've cooked that toroid during testing and it's dead now
3. It's not rated to 50MHz, and that's causing a problem.

I've got some T68-6 on order (-6 is rated to 55MHz vs 40MHz of the -2), so will replace the two single cored ones. But wondering if going to T80-6 or T130-2 or T130-6 might help if it's saturating.
The -6 mix is only ur=8.5 not ur=10, so the windings change slightly (9.4/14 instead of 8.7/13), but shouldn't need any other changes.

I'd like to run FM/FT8 at 30...40W so any of the others I should be upgrading?

Thanks,
Roger.

Hi, Roger
50MHz frequency requires air core coiles with silver plated wire.
An other way - use resonant antennas with no tuner, for that frequency it is very easy and not expencive due to short wave.

Hi David,
What about the -6 mix ferrites?? They are 0...55MHz rated, and other than 8.5 vs 10 relative permeability they look to be a drop in replacement.

Roger, I don't believe in that, because I faced in simple BPF when air core coils with simple 1mm magnet wire became very hot on 50 MHZ. Yaesu used silvered 2mm wire for that .?
But you can try the mix #6.