Topband: BSEF Array

[donovanf at starpower.net]

Hi Mark, 

You will enjoy using your new BSEF receiving array. K1HTV was a big fan of my BSEF array in the DX contests. 
Ask W3UR how he likes it. His T6T topband QSO was made possible by the BSEF array, impossible to copy on the 900 foot Beverage. 

Starting at the top of the photo: http://pvrc.org/bsef/bsef.html 

Three inductors in series (two fixed inductors and a toroidal inductor) to set the resonance to 1830 kHz as measured by an MFJ-259 at the 50 ohm test BNC. 

Two resistors in parallel to set the VSWR to 1:1 as measured by an MFJ-259 at the 50 ohm test BNC. 

Two resistors in parallel, accurately set to 25 ohms (measured with a digital ohm meter) connecting the 50 ohm test BNC to the 75 ohm BNC for the RG-6 feedline. 

I use quad shield gel flooded RG-6 feed line purchased from : 
www.therfc.com part number WIR-RG-6QFLOODED $0.11 per foot 

Yes, those are short RG-58 coax cables in the box, the very short lengths of RG-58 do no harm. 
After the photo was taken I replaced the RG-58 with RG-179/U 75 ohm teflon insulated coax (it made no difference at all...) 
http://www.therfc.com/coax.htm 

Good luck with your new BSEF array! 

73 
Frank 
W3LPL 





----- Original Message -----

From: "Mark Luhrman" <w4svo at att.net> 
To: donovanf at erols.com 
Sent: Monday, July 29, 2013 4:41:05 PM 
Subject: BSEF 



Hi Frank, I want to make one of these. I need some clarification on the pictures. I noticed that you have extra resistors in parallel. Are these extra ones on the side that goes to the bnc connector are only there for measurements and then taken out? I am not quite sure because you state you use a 36 ohm to match the antenna. The other question the mini splitters are 75 ohm. But in the picture you use RG-58 which is 50 ohm. So I am confused about this also. Mark W4SVO