[Hallicrafters] Part request

[Roy Morgan]

On May 7, 2009, at 5:43 PM, Jim Liles wrote:

> I am looking for one or a dozen VHF powder transformer cores.  They  
> are 1/2
> x 3/8 x 1/4 and have two channels for wire through the 3/8 "  
> dimension.
> Believe they were used for 4 to 1 matching or BALUN.

Jim,

Called "binocular cores" and I think they are available.  Try Amidon,  
or the folks who actually make the things Amidon sells.
https://www.amidoncorp.com/
Amidon calls them "Multi-Aperture cores", and offers them it type 73,  
61,and 43 materials.  Type 61 works at 10 to 200 mc.

You'll need to decide what the core material is but that will be easy  
when you find the information about the available cores.
See the Amidon specifications page:
https://www.amidoncorp.com/pages/specifications
Type 61 works at 10 to 200 mc.

The multi aperture cores dimensions are linked at:
2-34 Multi-aperture, Ferrite Bobbins, Balun & Tuning Cores



Mini-Circuits sells transformers of small size and *may* sell such  
cores.

Roy

Roy Morgan
k1lky at earthlink.net
529 Cobb St.
Groton NY, 13073
Home: 607-898-3607
Cell: 301-927-7794