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472 khz sota activation- any chasers available?


#1

first of all i wish you a merry xmas and lots of new gear for our hobby.
Just finished building my portable transverter for 472 khz and my portable loading coil.(10cm of diameter and about 14cm long).
Let me know if there is anybody outside interested in working me on 630m from a sota hill.( crossband(80m) possible).
vy 73 de wolf DK1HW


#2

Richard @G3CWI was experimenting with some 500kHz activating a few years ago.


#3

Thanks to the support of wolfgang, dk1hw I am currently working on a portable 10Watt transverter for 472 khz. Since I have no experience with portable antennas for this wavelength, it will take a few days or weeks until the first activation.

73 chris


#4

I hadn’t been thinking 630m for SOTA operations but I’d be most interested to see what you’ve come up with. Have you any pictures or drawing you could share? I wonder what the easiest way to add the band to my KX3 would be.


#5

hi eric, hi folks,
on the attached pic you can see my portable station.

In the swr-meter there is a transverter(G3XBM-version)with modified swr-bridge for 630m.
On top in yellow there is my loading coil which is about 820uH in max by a Q from 80 ( 350uH Q 125).
On top of the loading coil you can see my antenna current meter and my antenna transformer(15ohms - 100ohms to 50 ohms).
Eric, this transverter works in split mode which means on tx the signal is mixed to 472khz and in rx it is direct.
That works perfect with the FT 817( my ODX in that configuration is abt. 1165km).
J also have a KX3 , but i can´t split over bands. ( maybe it works when i use memory?).
I hope to be qrv soon on 630m.
If you really interested in 630m please read ON7YD " antennas for 136khz "which is also good for 472khz.

wolf , dk1hw


#6

:smiley: :smiley: :smiley:


#7

Heh, more portable than anything I had in mind.


#8


#9

A group of us in the Camb-Hams (the social side of the Cambridgeshire Repeater Group) will be doing a group project building a 472kHz transverter in the new year, it will be based on a design by George M1GEO. It’s a new development based on his previous version shown at:

https://www.george-smart.co.uk/radio/472_khz/472_khz_transverter/

Several of us are also SOTA fans so we should manage some 472kHz SOTA activity.


#10

All the best for 2018 !
that would be fine !
over xmas i was portable qrv (antenna 41m long horizontal ca. 13m and rest inv v down to 4m and could manage to make
2 qsos . for earth i rolled out a wire abt. 30m under the antenna and additional take the earth from the powersocket
from the house. Had a little help from the snow which was about 10cm and this gives me a little bit more antenna current.
The most importent thing is the right time fer the right distance.
still looking for 630m partners.