SDR LPDA (300mhz-6Ghz)

[clanon 258]

Trying to make a "GOOD" Lpda , SCIFI VIVALDIs from RFSPACE have NO GAIN (under 1GHZ) , Chinese LPDAs have LOTS of LOSSES and mismatch...50 ohms FLAT ALL band , just a peak close to 1ghz unavoidable on this antennas...

[clanon 258]

1.5-2mm PES dielectric...RG316 low loss cable...

[clanon 258]

0.1 Brass sheet (can use ANYTHING you have)

[clanon 258]

[Admin 2578]

Clanon,could you give some dimensions?

[clanon 258]

DXF , easier...TWO and a bridge in the back...+ CST (2019)

Untitled.cst

Untitled.dxf

The one on the picture has a LOW FRECUENCY enhancement (200mhz) and a REFLECTOR PLATE some 10 cm in the back 

Edited November 14 by clanon

[clanon 258]

Should I try with FR4 double sided PCB ?...(it must work but HIGHER LOSSES...maybe z would change...tho) Tomorrow i confirm it...

[clanon 258]

1.5 mm distance between sides (Feed Line) 

Edited November 14 by clanon

[clanon 258]

Feed line on FR4 needs to be THINNER 5 mm or less...to get 50 ohms...

[clanon 258]

FR4 version...not so good...High losses and some mismatch , lower gain...

fr4.dxf

[clanon 258]

On 11/14/2024 at 4:41 AM, Admin said:

Clanon,could you give some dimensions?