Jan 27, 2014
Category: General
Posted by: m0cke

I've finally done it, M0CKE/m again !!

CMS - 1.11.1 - Baltra

4 Square for 40m

The 40m 4 square build has begun, using a circuit board from SJ2W and informaton published by TK5EP i'm building a hybrid coupler similar to the COMTEK boxes commercially available.

T225-2 cores were ordered from Amidon, 2mm enameled copper wire from and all other components from Rapid electronics.

The build commenced with first building a L/C meter kit from G4HUP which arrived very quickly, following the instructions the simple assembly and testing was compelted in arounbd 2 hours.

Next I wound the first torroid to test, adding 2 extra turns as suggested then measured the inductance with the L/C meter to find the inductance was to great. Turns were carefully removed and adjusted until the 1.13uh of inductance was acheived, this took around 2 hours.

The second inductor was wound and tested in about 30 minutes as the first had given me the accurate turns.

Both inductors were fitted to the PCB along with the relays.

I'm now waiting for the delivery of the enclosure and HV capactors before any more can be done.

The control box will be based on a Arduino microprocessor with LCD display and more information on this will follow.

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