CHECKING TOROID CORES WITH A DIP METER , DIP METER TIPS

Checking toroids purchased at a Hamfest with a Gid Dip meter or solid state dip meter . I wanted a method of testing toroid cores to determine if they were good for RF use in a QRP transmitter . So playing with the Heathkit tunnel dipper I found an easy method to determine if a toroid core was a Common Mode noise filter core that you put on a computer cable or a power cable in a rig to cut down EFI noise or is it a toroid suitable for RF .
I have gotten some BIG toroids and wanted to make a balun for HF only to find it did not work WHY ? you say . Well because it was not an RF toroid core
it was a Noise filter core called a common mode noise filter core these are not suitable for RF . So shown in the video is a simple way I figured out to check toroid cores to see if they are ok for RF use . I then tried using the Kenwood DM-81 dip meter and found it worked much better than the Heathkit tunnel dipper the tunnel dipper gave a small hard to find dip using this method . I imagine that the heathkit tube type dipper would work well as would a Millen grid dipper . 73 Bob

[@SpinStar1956]

I have a HM-10A that was given to me by a friend who is now since passed. He ended up using some foam to keep those coils in place. When the foam wears out, I think I will construct your plexiglas one.
73… 😊

[@hustonherman7870]

Hi Robert, outstanding video. So I have a dip meter and I am checking some hopefully hf toroids. Question I only have a 100pF capacitor. My readings only deflect the needle somewhat near the end of the scale only. Is this what you would expect? And once I receive the 50pF and use as you illustrated will I have better readings? I do have two 240-43 Toroids from commercial source. Thank you in advance.

[@brianveitenheimer4492]

I just got a nice old grid dip meter. This is going to be my first project.

[@sfdntk]

Thanks Robert, you taught me something new today.

[@dougtaylor7724]

Thanks. Very good instruction video.

[@countryside8122]

Are any from the computer power supplies any good for RF? I have quite a few yellow ones from computer power supply.

[@mirrar01]

Very interesting, and I can finally figure out what all these random toroid Coils are for I have

[@acestudioscouk-Ace-G0ACE]

Really useful, thanks!

[@pavil58yt]

Who remembers the Measurements Corp Model 59 GDO
?

[@lampshadesneeded]

Can we use nanovna the same way?

[@niknam.]

"three turns .."😂😂😂

[@Yorumcu63]

great thank you