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Old July 4th 07, 06:10 PM posted to rec.radio.amateur.boatanchors
Engineer[_2_] Engineer[_2_] is offline
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First recorded activity by RadioBanter: Jul 2007
Posts: 41
Default Wanted: BC-348R info

On Jul 4, 11:20 am, wrote:
Note to all:


(snip)


************** I'm using a matching transformer from 300 ohms (LO) to
8 ohm speaker. I plan to install a proper OPT to match the 6K6 to 8
ohms but leaving the original there for posterity.


The trick is that the 6K6GT isn't biased the way it would be to
deliver a couple of watts as a speaker driver. Sure it will work, but
it will be running flat out.


**************** I'll check that and, if needed, rewire it. I
noticed the screen voltage exceeded the plate voltage by quite a bit.
A 6K6 o/p stage is dead easy to brew up.

(snip)]


The problem with that is the dynamotor, if not running, will present a
near-short circuit to the power supply. And the 24 volt heater line is
connected to the dynamotor input, so it will be shorted too.


************** No, it is now totally disconnected

By simply removing the dynamotor assembly and putting in a dummy
chassis so the loose wires don't short, you can retain the rx wiring
and run from an external supply. Then if you ever want to drop in the
dynamotor and run from 24 volts, you can do that too.


************* B+ P/S is a separate Heathkit reg. unit and I don't want
to lose the dynamotor over the next 50 years! So. I'll just leave it
in the chassis for the next collector...

(snip)

Cheers,
Roger