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Please, do not send me any money yet! Now I have 6 orders, which takes us to
the 100+ pricing for the BC547B so everything will become slightly cheaper.
Thanks for your emails, I will reply individually as soon as I get the
chance, which probably won't be until Monday.

It's nice to see so many people joining this group and planning to build
this neat design.

I'm happy to extend my offer of bulk purchase components from Rapid
Electronics to optionally include for those who want them, some of the other
parts which you might not find so easily in your junk boxes. I'm thinking of
the 9V1 and 36V zener diodes, 7805 voltage regulator, 10x 1N4148 diodes,
trimmer capacitors, and possibly something to substitute the 2N2218 driver
transistor. All small components which won't much increase the weight, and
will still mean I can use small envelopes and not worry about special
packaging etc. I'll work out prices on Monday at my office, which is where
my Rapid Electronics catalogue resides ;-)

In his prior version Farhan was using two BC547 parallelled, and only
replaced them with a single heatsinked 2N2218 when the '547's were fried
during a long PSK31 QSO. Can Farhan or anybody else suggest alternatives
since I don't think Rapid sell the 2N2218?

Now a word about the crystals. Farhan recommends buying 10 and choosing the
closest 4 for the filter. I did so and chose the next closest one for the
BFO though this wouldn't really be critical. Measurement could be via a
frequency counter or zero beating on another receiver with digital readout
and coverage of 10MHz. I have a homebrewed counter in my HF receiver, you
can read about it on my webpage. But if you don't have either of those items
I can imagine a rather simple and cheap frequency counter circuit having
only 3 common 74HC-series IC's and a handful of LED's for binary readout of
frequency, providing more than sufficient resolution for the task. Failing
all of that I'd seriously suggest getting just 5 crystals and trying them
anyway. When I measured my 10 they were quite close and I think reasonable
results would be obtainable without the precise matching if suitable
equipment isn't available. I'm interested in other people's opinion on this.
If I can manage to find my notes on Monday I'll post my ten measurements,
and you'll see what I mean.

Any more orders, let me know via email. But remember, no money yet until I
make final calculations.

72/3 Hans G0UPL