G7NPL,

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send your email address to me at gerryohara@... and I will
send it directly to you.

73's

Gerry

--- In eddystone_radio_users@..., "Gerry O'Hara"
<gerryohara@t...> wrote:
>
> G7NPL,
>
> Much as I really dislike even the thought of modding Eddystone
sets these
> days (especially non-reversible mods that hack the chassis etc),
many years
> ago in my youthful enthusiasm I undertook an 'extreme' modding
exercise on
> my unfortunate EC10mk1. Mods included: xtal calibrator, NBFM
detector
> (Foster Seeley disc), noise squelch, 'Burns' 2-Metre converter
(using 4 to 6
> MHz tuneable IF), fine tuning (including external fine tuning), S-
Meter with
> amp, stabilized psu, AF239 RF (TR1), FET mixer stage (2N3819
circuit in
> place of TR2), Q-multiplier (with peak/null, and variable notch
depth &
> bandwidth), pump-diode fast/slow amplified AGC, external muting,
and a
> product detector (the latter may be of interest to you). I hunted
down the
> circuit for the product detector and a few other of these mods and
have
> attached a pdf compilation of these - apologies for the poor
quality but
> these scraps of paper were found stuffed into my original 1964
EC10mk1
> manual, complete with all my circuit board layouts etc. I recall
that the
> product detector was one of the first mods I did to the set and it
worked
> very well, making SSB resolution much better. If you don't mind
further
> modding, I would suggest that switchable fast/slow AGC is also
added as well
> as fine tuning is you have a mk1 set to further improve SSB signal
handling.
> Also, improved stabilisation of the psu improves frequency
stability quite a
> bit - needed for receiving SSB at higher frequencies.
>
> The product detector (page 1 of attached) can be added with
relatively
> little modification to the original circuitry (see page 3 of
attached) and
> could be easily reversed if you ever want to revert the set back
to original
> condition. It used a couple of matched 'period' OC44 PNP
germanium
> transistors (though type is probably not too critical) and was
constructed
> on veroboard (this was before I started to etch my own boards, so
was likely
> constructed around 1973). I would have taken some photos for you,
but the
> set is in my mother-in-law's garage in the UK (I live in Canada) -
probably
> the best place for it poor thing.... RIP. Maybe one day I will
rescue it
> and reverse as many mods as I can.
>
> Hope this helps a bit.
>
> 73's
>
> Gerry G8GUH
>
> _____
>
> From: eddystone_radio_users@...
> [mailto:eddystone_radio_users@...] On Behalf Of
qaxdgb7
> Sent: September 8, 2006 8:57 AM
> To: eddystone_radio_users@...
> Subject: [eddystone_radio_users] EC 10
>
> Hi the eddystone ec10 has bfo that is ok for cw but it is very
hard
> the use on ssb dos eney member know how to modifi the bfo for
ssb.has
> eney member don this mod thanks qaxbgb g7npl.
>