What Inductance does your HH coil measure

[6666]

I have made a coil from the specs given by Carl
for the HH, 26 turns, 10inch, .4mm enamel copper wire

When I first made it the wires were loose it measured on my meter about 490 micro Henries.

Now I have started putting some tape on it the wires are more compact
and it now measures about 510 micro henries,

When I complete wrapping the coil in tape the inductance is going to go way up higher
this sounds like way to many micro henries

Just wondering what anybody else has measured their coil to be ?

Of course my meter could be wrong, but I have made the coil to the specs given so it should work ?

[6666]

All
it seems I have answered my own question about the original HH coil, which is 26 turns, 10inch, .4mm enamel copper wire.

In reviewing the 2005 hammerhead article it mentions coils being in the region of 500uH,

in using the coil calculator made by Qiaozhi , which uses enamel copper wire
it says that coil should be around 577uH, I have not finished tightly wrapping my coil yet
to increase the final inductance so I can measure it with my meter, maybe my meter is correct, as loosely wrapped it measures 510uH.

But 577uH seems a very big inductance for what we are doing
has anybody been using smaller coils on their HH for coins and jewellery
at the beach ?

[Qiaozhi]

in using the coil calculator made by Qiaozhi , which uses enamel copper wire
it says that coil should be around 577uH, I have not finished tightly wrapping my coil yet
to increase the final inductance so I can measure it with my meter, maybe my meter is correct, as loosely wrapped it measures 510uH.

How did you get 577uH?
It should be 546uH.

[6666]

oops you are right the radius is 127 mm
I used my wifes dress making tape measure
and folded it in half at 10 inches
and did not look at the measurement correctly
added 10mm.

[Qiaozhi]

oops you are right the radius is 127 mm
I used my wifes dress making tape measure
and folded it in half at 10 inches
and did not look at the measurement correctly
added 10mm.

For future reference, 1" = 25.4mm.