Hi Gary
Yes, I am a member of MWC and I've avidly read your
fanatical
loopstick and other articles. Indeed Gary, it was your article in
MW
News January 2008 about the Sony SRF-59 that rekindled my interest
in
MW DXing. You've got such a readable easy style of writing
that
retains the interest, making the reader want more. Your
sheer
enthusiasm really leaps from the page. Sincerely, have you
ever
thought of becoming a professional author?
There are many who
owe you for founding the Ultralight movement. Not
just DXers, but also the
radio vendors. The hobby could not have a
better advocate! Your articles
have been responsible for my obtaining
the SRF-59, SRF-T615, DT-210L &
DT-400W radios and generally 'doing'
radio again. Unfortunately I've yet to
hear any TA DX on any of them.
73
--
Michael Slattery
G8PNX
Sheffield, UK
On Sat, 4 Apr 2009 14:37:39 EDT, you
wrote:
>Hi Michael,
>
>Thanks again for your filter
modification work, and your kind comments.
>
>Actually both Guy
Atkins and Steve Ratzlaff are far more experienced in
>filter
modification work than me, and I've simply managed to learn a few things
>by having the privilege of working with them. My own contribution to
the ULR
>experimentation efforts here has been in loopstick
improvements, in attempts to
> make these tiny radios as sensitive as
possible. If you are a member of MWC,
>you may have seen a few of my
fanatical loopstick articles that were
>published in Medium Wave
News.
>
>About a year ago, I learned the harsh lesson that
sensitivity improvements
>alone were not going to make a major
difference in chasing 9 kHz-split DX with
>Ultralight radios. A small
radio needs both a major sensitivity boost and a
>major selectivity
boost in combination, to make a radical improvement in
>overall
performance.
>
>By a tremendous stroke of luck, one of the
primary filter experts in the USA
>(Guy Atkins) lived right in my small
home town, here in Washington state.
>Our cooperation last summer
(along with contributions by John Bryant) produced
>the first major
breakthrough in ULR 9 kHz-split DXing performance, the fully
>modified
Eton E100. Steve and I were attempting to create something similar
>with the DT-400W in the winter, but despite our unrealistic
expectations, we
>ran up against the harsh reality that all the
commercially available 450 kHz
>IF filters are mediocre for
transoceanic DXing.
>
>73 and Best Wishes,
>
>Gary
DeBock
>
>
>In a message dated 4/3/2009 7:45:52 P.M.
Pacific Daylight Time,
>knallebo@yahoo.co.uk
writes:
>
>
>
>
>Hi Gary
:)
>
>Thank you for your kind thanks for my mod articles. I'm
sorry that
>some folk may have been misled into thinking the
selectivity
>enhancement would be much greater.
>
>There was
not that much effort expended in development. On obtaining
>both the
DT-210L and the DT-400W I was extremely disappointed by the
>very poor
selectivity. My gut reaction was that I had to do something
>about it
and whilst I was 'at it' I took a few photos reckoning that
>it may be
of use to someone somewhere!
>
>I'm fully aware of the performance
provided by the premium filters you
>and others have been using for
9-kHz split DX chasing. I've used them
>myself in my AOR AR7030 for many
years but not yet in a ULR.
>
>Some thoughts: I know you and Guy
Atkins have spent quite some time
>developing filter mods for various
ULRs. I wonder whether it might be
>worth investigating the Collins
Low-Cost Series of mechanical filters
>that have a superior passband
ripple to ceramic filters possibly
>enhancing the intelligibility of
reception. Expensive, but when only
>the best will do. Inrad have a 2kHz
8 pole variant:
><_http://www.inrad.http://www.ihttp://www.inrht&cat=5&p_
>(http://www.inrad.net/product.php?productid=19&cat=5&page=1)
>
>or a 2.3kHz 10 pole variant:
>_http://www.inrad.http://www.ihttp://www.inrht&cat=5&p_
>(http://www.inrad.net/product.php?productid=18&cat=5&page=1)
>
>In the DT-200VX and DT-400W, if space cannot be found for the
filter
>within the case maybe one of the AA cells could be disposed of
to
>create a space for the installation the filter. The remaining AA
cell
>bay could then be loaded with a 3.6V Lithium AA
cell.
>
>Thanks once again for your
consideration.
>
>73