#gdx #toroid QDX Trifiliar toroid #toroid #gdx


Stefan U. Hegner
 

Hi there,

just completed the soldering for my QDX yesterday.

However, what bothers me is the following:

After soldering of the trifiliar toroid to the PCB, there seems to be continuity (less than 2 Ohms) between all 6 connections. - That can't be right!

With all the other torids I burnt off the enamel with a lighter and sanded the leads. For the trifiliar I went with Hans suggestion to solder-off the enamel, because of the 6 connections with very thin wire. Before soldering to the PCB I checked the A-A, B-B, C-C and no A-B, A-C, B-C connection on toroid only, while having the (insulated) wires placed in the holes and having all wires approx. 2cms too long and after having burnt off the enamel at the very end.

The twist of the trifiliar winding starts about 2-3 mm from the PCB on the top level of the PCB.

Question: Do you deem it possible that the soldering-off of the enamel at the end created a continuity between the three wires? I had a 16W iron and applied it 10-15 secs. per connection. Or is it more likely, that I messed up somewhere else in the process?

... just wanted to check before de-soldering and measuring again.

Is the exact type of the enamel wire crucial? I've got only 43cms of the thin wire left, but I have some thinner wire lying around.

Cheers,

Stefan.


DD5ET
 

Hi Stefan,

See this thread here: https://groups.io/g/QRPLabs/topic/91746631#87032.

I asked the same thing and the answer is basically, yes, after mounting the toroid there is continuity between all combinations of all 6 wires.


Stefan U. Hegner
 

Hi Scott,

Am 24.06.22 um 00:33 schrieb DD5ET:
See this thread here: https://groups.io/g/QRPLabs/topic/91746631#87032.

I asked the same thing and the answer is basically, yes, after mounting the toroid there is continuity between all combinations of all 6 wires.
thank you, very helpful and saved me a lot of useless soldering out and in and the frustration with all those tiny wires ...

Vy 73

Stefan