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flipper flipper is offline
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Default "Beam Me Up, Scotty" (Beamus) AM Transmitter -- first prototype

On Mon, 11 Jun 2012 12:50:03 +1000, "Alex Pogossov"
wrote:


"flipper" wrote in message
.. .
Okay, so I like to make up cutesy names

I wanted to do 'something' with a 6ME8 so I tried using it for an AM
transmitter and the first prototype works rather well. Bandwidth is
'too much', less than 1 dB down at 18 KHz, but we'll worry about that
later.

This is a 'dollar days' special, 2 whole bucks worth of tubes, and L2
is a UHF converter coil scramble rewound, so that was 'free'. Power
supply is from the same converter and if the remaining issues get
worked out it'll probably end up in that cabinet as well (but where to
put the air variable?).

The schematic is rough, but should be rather self explanatory, and the
ganged tuning hasn't been fleshed out yet. I'm still using separate
caps while jiggling things around.

Orphaned web page, not yet ready for prime time, has a recording of it
playing through a table radio.

http://flipperhome.dyndns.org/Beamus.htm


But the smartest arses (aussies of course, he-he!) put their AM transmitters
in the vintage radio cabinets.
http://www.ebay.com.au/itm/140770446...84.m1555.l2649



Interesting you bring that up because it was my original 'cost saver'
idea before the UHF converters and I even bought a supposedly non
working Philips radio to use. Turned out the radio only needed one
tube, which I had. It could also use a recap but it's in good enough
shape I didn't have the heart to scavenge it.

I might resurrect the idea for the air variable and dial indicator but
the biggest problem is I want power transformer isolation and most
don't have one (at least not the AA5s), nor 'extra room' to fit one. I
notice that Little Nipper does but it's 240 VAC.

I think my 2 bucks 2 tube Beamus scope shot looks as good as his 5
tube job