ref: www.radiocom.net/600M/LOOP109.jpg
Hi Dave, Lowfers,
If you wouldn't mind, can you give us a more detailed pix
and/or description of the coupling. It looks like you've
got a series tuned circuit at the end of the feeders?
How is it coupled to the rig? Thanks in advance.
73, J.B., VE3EAR
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Howdy, JB
I hope to have spelled it out better with this version. It is as simple as I
can undertand and works DX.
Between it and the SDR-IQ RX could copy QRG of the SAQ Alternator revs.
Yes, that in fig. 1A is a series tuned circuit which includes the 'Pennant'
LOOP and all of it is a part of the RFPA tank.
The 6 turns are about optimal for TX coupling @ 600M so I just tune out the
X component with the vacuum cap. to zero...
Happy TX, no red plates on high power... But don't forget the OB2 regulator
across the 10' RX loop twin lead as first stage protection or else no more
J310s as they go POOF...
See also other forms of feed that me think and Bill Ashloop, WE2XGR/4 said
to try.
In RX it acts as a transformer primary which can be tuned from 10kc, 24kc.,
60kc, 137kc., 185kc., NDBs, 600M etc. with the help of the 4 total parallel
decade cap boxes which give 0-1.111 mfd of cap in 100 pf bytes...
I always wanted a 0-1mfd variable, affordable, but don't do too much TX with
it or you'll be back on e-bay for a replacement...
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Dave
Although the smaller antennas work I have found the signals are well down
compared to the larger wire antennas.
My 40 metre resonated loop on 500 Kcs is not as good as the 1/4 wave inv
L, also I have noticed small loops in the target direction are well down on
the bigger wire antennas. I am talking about weak signal detection.
de mal/g3kev
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I agree, Mal, and that is why I had to do something about the 10' loop being
kinda deaf but at least it got rid of some noise...
So I added the parasitic loop around it ( and it then doubled as good TX
antenna as well ) and the RX now needs more local noise abatement than more
gain. This is the best I have tried to date, now for a phased e-probe way
out in the woods... Hopefully by this season end...
I guess you could call this a large wire loop ( 430' around )... I can see
where the 65' vertical section is the only real useful part...
At least 3db isn't going in to the soil or for making plasma on the high far
end...
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Hi Dave, thanks for the post. Nothing like a discussion about simple
antennas which work magically :-)
Your sketch shows a short at the point where the 1' wide feedline
connects to the loop (if I interpret it correctly). May I safely
assume that's an oversight and not some fancy hairpin matching device?
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Yes, simple or I don't get the hang of em... Magic? Seems more like FM...
Yes, the 'tune' modulation goes from 10kc to HF, even 6M. Above 6M is where
that shunt 'L' is used...
You had me worried about that short so I measured the .jpg and it was over
10megohms, guess I got lucky this time, but have since replaced it with an
air insulator..
No wonder they couldn't copy me up in VE2/3 land... Or cuz that is
broadside??
Sure wish I knew how to tangle with EL-NEC... I see a weak doughnut coming
out of the 65' vertical and the other two wires wasting power straight up
and down but necessary for the 'end feed'...
Tell you what I'll do... Come the proper Lunar SHA and DEC I will power up
with 1296 blunderbus when the moon is target for that VEE on the right hand
side.... Will it echo??
10kc. to 1296 mhz. and reaching...
Next stop, ANOTHER parallel loop made of 500' of Andrew 400 heliax, new from
local dump... Parallel loops lower R, yes??
3 element loop?? What would I ever do without a good 60 pounder compound
bow ...
How about a triplexed 137-185-505 TX loop... Look @ the wire you'd save...
GI4DPE, M0BMU, G3KEV, SK6RUD, SM6BHZ, DI2AM seem to come thru good any night
that they are on...
Sometimes noise + 2db and sometimes WAY up out of the noise in 20s-30s
DBs...
Best regards and straight ARGO lines to ALL,
Dave ( in the Colonies ) WD2XSH/17
* All with proper TNX to Reggie@BO, Bill Ashloop and Bill DeCarle without
whose mind prodding I might still be on 80M 2IQ BPSK...
CQ EU ( RX only, mind you ) I don't wish to be sent to Coventry...
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