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Ok G..
That looks technical ! Im just using one of the
coils from the WW2 Tx 6 inch x 4 inch
BC something as a tapped auto , step
up transformer , was a plug in linked centre
tapped coil until the cellulose based
coil spacers melted , now its a re-hash with
perspex and araldite
That floating primary idea is worth looking
at for 500 , but as my atu is in
the out house , and power is fed with 40 ft
cable ..im not sure what part the mains earth
plays in the Tx cct , H f the tuner
earth bonded to everything that conducts , same
used for 500 ....... a 1:1 50 ohm balun
would break the coax braid ( 90 feet feed length) ,
but there is still the power supply for the
tuner , so the earth is back again , there is very little
reflected power on 500 , so something is 'right'
but as for RX , its just too noisey to be
any use
G..
Sent: Sunday, April 22, 2012 8:51 PM
Subject: Re: LF: Re: UA4WPF G8HUH 2200m 3615 kms !
Graham,
Yes, interesting comparisons there....especially
Op4H.
My 500/136 antenna feed/coupling transformer is wound on a
couple of large toroids. When I change from 500 to 136 I only need to change the
primary & secondary by 2 turns, of course I do add more base
loading inductance for 136kHz.
The primary is floating ie. no direct connection from the
feed ground to the antenna ground, that works best for me.
(attached)
73, Gary - G4WGT.
----- Original Message -----
Sent: Sunday, April 22, 2012 8:22
PM
Subject: Re: LF: Re: UA4WPF G8HUH 2200m
3615 kms !
OK Gary ,
A spectacular launch for the new system by any
standard , full data decode !
Yes , good point , the actual minimum decode level
is now slightly better than the first
versions , but OP2 s/n is about the same as wspr ,
so that should give a reference as the
original s/n was calibrated using
Fldigi and wspr as the benchmark, J came
to the conclusion that the levels where
not realistic and revised the calibration , using
the path-sim software.
If you subtract 8 dB , is that close
to the original level , if
wspr shows -34 dB to Opera ( and
Ros) -26 dB for the same conditions
? OP8 is then -40 dB old money and
OP32 is 49 ...
Interestingly that makes Opera
4H audio - 55 dB old money ...
Tempted to try 136 as well , I assume , A big
series inductor with the 500 tuner set up
would bring everything into resonance ... or at
least be a starting point ?.......but what of
the auto feed transformer , if thats
non reactive , then the frequency should
not change the 50 ohm Tx view ??
73 -G..
The eating of the pudding is in the
proof as they say after 2200 hrs , the first TA
decode was OP8 @ 3667 K ,
using a Parasol-on-a-Stick MK1 back garden
array Tx Ae
Sent: Sunday, April 22, 2012 7:03 PM
Subject: Re: LF: Re: UA4WPF G8HUH 2200m 3615 kms !
Graham, LF,
I have omitted the December 2011 decode of
VO1MRC on 136kHz with Op8 in the other direction giving a distance of
3667km.
Of course conditions would be very good then, not able
to compare the -20dB S/N due to changes in the way it is now
calculated.
73, Gary - G4WGT.
----- Original Message -----
Sent: Sunday, April 22, 2012 6:42
PM
Subject: Re: LF: Re: UA4WPF G8HUH 2200m
3615 kms !
Graham,
I bet your ears are still frying bacon
& rattling morse out :-)
Probably will be Op32, my nearest to that in Op8
is...
20:51 136 RW3ADB Op8
-34 dB 2553 km
..........-34dB being about the limit of Op8
73, Gary -
G4WGT.
Original Message -----
Sent: Sunday, April 22, 2012 4:39
PM
Subject: Re: LF: Re: UA4WPF G8HUH
2200m 3615 kms !
OK ,still recovering from listening to white
noise for 6 hours last night , once a year
is enough of this modern CW ,
vintage MGM-CW is far less of a frazzle
Assume that was OP32 at that range
?
Tnx -G.
Sent: Sunday, April 22, 2012 3:17 PM
Subject: LF: Re: UA4WPF G8HUH 2200m 3615 kms !
Graham,
Just a slight correction :-
>and check the 'spots only from'
box,
Should read.....and un-check the "All Spots" box,
you will then have a local copy of band data.
73, Gary - G4WGT.
----- Original Message -----
Sent: Sunday, April 22, 2012 2:24
PM
Subject: LF: UA4WPF G8HUH 2200m
3615 kms !
All,
Opera 136 Up Date
Following on from the previous, some
interesting developments , on 136 , If your
station is web-linked , then in
either Rx only , Tx only
or Tx/Rx you will show on
the PSK-Reporting map, this was set
to ensure the status of both Tx and
Rx stations was available to all. after
all one is no use without the other !
As there is still no 'dedicated
storage' for the on-line data , If you
wish to monitor activity on a particular
band , you can simply run Opera , set to
the required band and check the 'spots only
from' box , you will then have
a local copy of band data .
some stations have added text to the
beacon 'test only - no RF' or similar to prevent
misinterpretation.
NB : These are full DATA call sign decodes
, so are the bare minimal exchange
required to claim a qsl or qso for
1 or 2 way , Opera is purely based on Data
processing and Digital signal processing and has
'no' deep search or fuzzy logic decisions
to assist in the data recovery ,
similarly for the QSO option, allowing
15 Chrs to be send in 120 seconds at
a nominal -20 dB s/n (ref to Sim-Path
simulation software)
UA4WPF decoded by G8HUH 2200m OPERA
3615 kms 00:39:25
This seems to be OP32 mode , but
monitoring stations can run 'two'
opera sessions , from the same sound card/pc ,
set OP8 and OP32
JH1GVY recent Tx addition to the
JA group of 8 136 beacons regularly
showing on the psk map
Welcome activity from down under
Decodes over 24 hours
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