V72a Plate Inductor

good ol #37 comin at ya,

Haufe A.Dr. 2  1V74

looks like a pipe bomb, do not try to get this thru airport security,  8)

take off the tape and grab some vice grips and you are ready for some fun,

looked like rust at first, i thought what kind of fool would leave a V module out in rain,

but no! it is just decomposed foam,

now if you have one of these, it will probably rattle when you shake it,

but don't use it for a maraca, you will break the core!

the gap glue has long since disintegrated, so inductance will be very low,

nice 3 chamber bobbin, shielded in a mu can, smooth winding, nice core,

probably sounds like shit!  ;D  no, just kidding,

i wonder if that 1000AL could possibly be the Al number, seems high,

DCR:  15.35 K ohms, Turns: 22,200,  500 Henries,

Green wire is Start = DCV, Red wire is Finish = Plate, carries 1 ma DC,

Inductance:

5 hz - 700 Henries
10 hz - 530 Henries
15 hz - 500 Henries
20 hz - 490 Henries
40 hz - 447 Henries
100 hz - 463 Henries
1000 hz - 1130 Henries
10,000 hz - 5 Henries

so L starts dropping and the picks up again, peaking at 1000 hz and then dropping off for good,

that ferrite core has a different loss per frequency curve than regular steel,

wire size is in the #48 - #49 range,

only unwound 1 chamber, figure we can multiply by 3,

we had 7400 turns on the first chamber so figure 22,200 turns for the whole thing,

Al value would be derived from

L = N^2 * Al,  (nano Henries) pick max inductance which is at 1000 Hz, so

1132 * 10^9 = 22,2000^2 *A l,

Al = 1,132,000,000,000 / 22,200^2,

Al = 1,132,000,000,000 / 492,840,000, 

Al = 2297,

so maybe that 1000Al number is correct,

lets try 500 Hernries, the value for 20 hz,

500^9/492,840,000 = 1015,

well what do you know, this is a pretty good chunk of something,

next...

totally over the top, there.