[ARC5] ARC model D

[Michael]

-----Original Message-----
From: arc5-bounces at mailman.qth.net [mailto:arc5-bounces at mailman.qth.net] On
Behalf Of arc5 at ix.netcom.com

> Actually, the AAC SCR-183 / -283 never got beyond the QRP power level,
running 
> essentially 1.5-3.5 watts.

Hmmm ... 10w plate input says here in the book ... yeah, I can see it.  And
to think these are the "improved" transmitters.  Maybe they should have
taken a cue from the Navy?  Oh, wait, they wouldn't do things like that.
Service pride and all that.

> I've experimented with the MO and PA, but not so far with the modulator.
1626 triodes 
> work, as do triode-connected 6AQ5s and 5863s.  All neutralize and tune-up
fine.  I'm 
> thinking of running an extra wire through the sockets and making a real
screen circuit for the 
> pentodes, just for fun.  Will get to the modulators one of these days.

Anyone have a wreck or two for me to play with?  This sounds like fun of the
finest kind.  But what are these "modulators" of which you speak?  :-D

> Remember, when you build it- as Mike Hanz kindly reminded me- the entire
set, be it SCR-
> 183 or GF/RU or ARC-5 or whatever, needs to be built on a decent ground
plane.  If you 
> don't, FMing and stray RF will bedevil you, even at 2 watts.

This makes a lot of sense.  They were designed to be operated in an airplane
which, except for a few stick and rag birds, were pretty good in that
department.

> I don't like working with big sheets of metal,

They may not be an ideal solution but cookie sheets or pans come to mind
here.  They're not that big, not that hard to work with and I suspect may
already exist in the kitchen.  As an extra added bonus, they're good for the
diet since there's no longer the ability to make those fattening cookie
thingies.  :-)

>> playing with the innards of an otherwise pretty-close-to-parts type Rx to
see if making 
>> something regenerative will help it become a CW Rx.
> I tried this with a -183 receiver.   The feedback level was crazy touchy;
a quarter of an inch 
> movement in the feedback lead meant either readable- if weak- CW signals
or completely 
> blocking the receiver.   I didn't find it to help much with selectivity,
either.  There's probably > a better way than just running a wire two stages
back from the antenna post, but I haven't 
> gone further yet.

Since the detector is a diode wired triode, I was thinking about making it
regenerative by the magic of making it back into a triode and diddling with
the circuit some.  A tickler winding would probably have to be added to the
coil sets unless I can do it all in the Rx itself.  Being essentially lazy,
I'd rather the latter.

> That being said, *my* "mission" for this set is to use it (and other
low-power aircraft sets) 
> into an amp I built to boast them up to the 100 watt level, and talk to
the local guys on 3890 
> KC.  They're loud enough to "boom-out" the side-winders ;-).

And what do the snakes feel about that?  :-)

What sort of amp did you create to do this?  All the gory details, please.  

Best regards,
 
Michael, WH7HG BL01xh
http://www.nationalmssociety.org/chapters/NTH/index.aspx 
http://wh7hg.blogspot.com/ 
http://kludges-other-blog.blogspot.com 
Hiki Nô!