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Showing posts from August, 2010

50Mhz LFA loop construction.

My 7 ele 50Mhz  G0KSC  beam  was a bit low band edge tuned.
The SWR went up to 1:1.3  at 50.300 and 1:1 at 50.000
the edge to edge dimension of the loop should be 245cm  according to G0KSC
I measured  246cm.
I calculated 1cm # 200kHz

Then i cutted  1cm of both ends (4x sawing) of DE1 and DE2.
That was not yet enough. so another time 1cm cutting. Then the matching was  optimal  between 50.000  and  50.500   rising slight to 1:1.2 at both ends.

The edge to edge size now is 142cm
I used 12mm Alu tubing  for DE1 DE2  and the other elements.
The end pieces are 10mm  2 x 1m each  leaving enough length left after bending.
DE1 & DE2   134cm  allowing 4cm both ends for the radius  of the end pieces. 
With the end pieces maximal inserted  the size is 142cm.

I tested it  F/B was real good  it all looks fine.
But the  50MHz  season is over and I replaced the beam with my HF multi-band again.
The beam waits on the attic for next season.

EME on 6M K2ZD with the 7ele LFA

This evening I could be in time to catch the Moon set .
I heard W7GJ direct when he started at his moon rise  -18  not bad here el: 018
Then I tried to work another call at 50193 K2ZD was active
A challenge to contact a more average EME station.
I had never heard another then W7GJ on this band but also
I did not really tried hard to do.
But now I copied K2ZD cq

cleaned up log:
50.190MHz
175400 6 -18 1.9 -57 3 * CQ W7GJ DN27 1 0     at   50190
QSY 50.193 MHz

180715 Transmitting: JT65A OH6MIK PA0O JO33 OOO
181717 Transmitting: JT65A CQ PA0O JO33
182200 2 -24 1.9 -24 3 * PA0O K2ZD FN21 1 0
182326 Transmitting: JT65A K2ZD PA0O JO33 OOO
182400 4 -22 1.8 -24 3 * PA0O K2ZD FN21 1 0
182800 10 -25 -26 2 RO ?
183000 10 -26 -27 4 RO ?
183147 Transmitting: JT65A RRR (Shorthand)
183500 Transmitting: JT65A CQ PA0O JO33
183515 Transmitting: JT65A 73 (Shorthand)
183707 Transmitting: JT65A RRR (Shorthand)
183729 Transmitting: JT65A K2ZD PA0O JO33 OOO
190300 1 -31 -35 3 RO
190400 4 -21 1.8 …

End of ES season

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I transferred my 7el DK7ZB to a 7 element LFA  loop feeded beam by G0KSC  just to see if that could be an improvement boom lenght of 9m80.
It seems okay the matching and radiation pattern seems clear.
First signal I  heard when I just erected the mast was D4C !  by coincidence.
It does not bring more signal   That was also not claimed  it should be a gain in noise and efficiency  the mechanical balance point was changed 50cm to the rear compared with the DK7ZB http://picasaweb.google.nl/jaapoosten/LFA11Aug?authkey=Gv1sRgCPCrivvtnImiHQ&feat=directlink
DK7ZB  with swallows gathering... meaning end of ES DX !

6M EME QSO with Lance W7GJ

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FB signals from W7GJ Lance this evening at Moon-set  west WSJT 7.07  under W7-64  on a Lenovo W510 Thinkpad.  K3 + U310 preamp ( N6CA )  7 ele DK7ZB 9m60

It's a struggle W7 i see no improvement against even W2000 !

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N1MM on my Lenovo W510 W7-64   with USB<->serial Prolific
After installing yet another Prolific driver  I tested again with N1MM on the laptop. 
At first some hours all was working normal but then suddenly again  the frequency readout and ruler in N1MM  starts to play wild . Complete random frequency's where shown.

it hangs after some time communication poll still runs with K3 but crazy display. Reset radio's will bring it back to normal.

Still not solved will have to get another USB converter based on the FTDI chip/driver to point out where this problem is coming from.
Another thing in W7  some button text no longer fits in the objects. 

Now I am testing with a rs232 breakout  box and will try to monitor the data over the port.
The same Prolific is working okay with WSJT and WSPR
I could run WSPR 24hours without errors
Also WSJT  the latest version 7.07 runs good  except for some error messages in the dos-box regarding to MSSQL access. It seems WSJT is assuming that MS…