idx concentric

[akasyto]

Pre AND Post

I did this today.Preamp output :Pre AND Post applaying Graphit 33 Spray on coil.

[golfnut]

Ok here is the DD27

So you have a slightly different phase relation here, this is all the issue is.

The option are - while viewing this osillogram... and waving ferrite / adjusting GEB pot... when you get rid of ferrite beep - phasing is correct.


1) move the physical location of the Rx coil WRT the Tx coil in the shell - if potted you missed a trick and too late..

2) Try a peice of ferrite on the shell to see if you find a location that give correct phasing, glue it there..

3) Add or remove Rx cap value in 1 or 2nF steps, the amplitude AND the phase alter.

4) Tweak the Tx cap value to see if the phasing alters favourably.

Or a mix of all.


Do you get single beep on pass?
Do you reject ferrite on DD and Concentric?


1) is favoured, others less so