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Author Topic: Ferrite Coupled Wire Antenna Test  (Read 91 times)

Offline NQC

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Ferrite Coupled Wire Antenna Test
« on: June 22, 2021, 0051 UTC »
Hey All,

I wound a quickie 280 uH ferrite bar with #24 DSC . I went with the big inductance to accommodate my "ultra light"  var cap box , which is kind of on  the low side value wise. A better/bigger var cap might do better , today was  just a quick check of a lash up.

Antenna was 40 ft run out , with another 40 or 60 ft wound on a large oat meal box  for base loading.

Taps on ferrite didn't seem to do too much so far , it seemed to like being fully at the hot end.

Also it liked being horizontal, vertical was much worse. 

The idea of doubling  it back to make it a loop put it into full short and killed everything.

2000 UTC, Sun at 45 degrees West-  so D layer most likely still in full effect.Low to moderate back round  noise, also QRN dx thunder storms ( at 200 + mi)
Receiver ATS 803A- sensitive and digital, but a small Fe bar inside.Narrow AM works really nice.

Test of known hyper weak New Yorkers :

570 WMCA noisy but there, slow QSB weak to sometimes fair, sort of usable.

1010 WINS  slow QSB, , mostly weak , but up to fairly usable at times.

No trace of either station barefoot.

Strong  New Yorkers :

660 WFAN weak audible on Fe, good on wire.
710 WOR   same.
880 WCBS fair on Fe , quite good on wire
1130 WBBR quite strong on wire but pretty bad QRM from a first adjacent local .

Ferrite also brought in a number of fair or stronger overloaded images from locals, WAY off of the   locals true frequency. But there were enough holes to squeak through, the DX frequencies were all clear .

Ferrite positioning kind of fussy ,but manageable.  To sum , some bugs but overall not too  bad.

Might still try long folded "feed line " scheme- maybe 40 or 60 ft top shorted , spaced at 1" . But so far , shorting back killed everything , as mentioned above. We'll see.

Also BIG progress today on 5 ft Octoloop.

« Last Edit: June 22, 2021, 0111 UTC by NQC »
Station main receiver : Bed springs to  blue razor blade detector to 2000 ohm cans to steam  radiator. Grid FN 42