Henry Torrid Filament Choke

[ko4nrbs]

FYI,
I found a picture of the Henry filament trifilar choke on EBAY.


Bill

[DMOD]

For which model of Henry Amplifiers?

Certainly not the Toroid Filament choke for my 2K-4. Possibly for a 2KD-5?

[ko4nrbs]

For which model of Henry Amplifiers?

Certainly not the Toroid Filament choke for my 2K-4. Possibly for a 2KD-5?

The EBAY listing says it was used in 3K Classic, 3CX1500A7 / 8877 amplifiers.
73,
Bill

[Opcom]

That choke is hot!

Reminds me of one from a RF power generator 13.5Mhz industrial type using a 3-1000.

[KD6VXI]

The 8877 is an 'external cathode' tube.  Needs a tertiary winding.

Henry used 10VAC with a center tap on some amplifiers (most) and 5v with a center tap on some. This is on the 500Z stuff.

The 8877 and 3cx800 stuff used the proper filament choke with the tertiary winding.   The 3cx3000 amps didn't, they used a proper filament xformer and choke design.

Henry also didn't have to cover 160 meters on almost everything they made. Until Steve got them to build a 160 amp, they never did except as custom one off amplifier chassis in the 8K chassis.  Good friend has one.

This was all hammered to death 20 years ago on the amps reflector, post grate parasitic debate....  Including why all 3 windings needed to be on the same choke.

--Shane
WP2ASS / ex KD6VXI

[DMOD]

For which model of Henry Amplifiers?

Certainly not the Toroid Filament choke for my 2K-4. Possibly for a 2KD-5?

The EBAY listing says it was used in 3K Classic, 3CX1500A7 / 8877 amplifiers.
73,
Bill

Not according to any of the schematics of the 3k Classic series.

[Dave K6XYZ]

For which model of Henry Amplifiers?

Certainly not the Toroid Filament choke for my 2K-4. Possibly for a 2KD-5?

The EBAY listing says it was used in 3K Classic, 3CX1500A7 / 8877 amplifiers.
73,
Bill

Here's a picture of the choke in my 3K Classic X MKll with 3CX1200A7
Obviously not the same as that EBAY pix.