[Boatanchors] BC375 and Dave's Excellent Tube Adventure, Part One

[Bry Carling]

That was great - "A little jiving on a Friday night."



On 25 Oct 2013 at 8:59, David Stinson wrote:

From:           	"David Stinson" <arc5 at ix.netcom.com>
To:             	<boatanchors at mailman.qth.net>
Date sent:      	Fri, 25 Oct 2013 08:59:24 -0500
Subject:        	[Boatanchors] BC375 and Dave's Excellent Tube Adventure, Part One
Send reply to:  	David Stinson <arc5 at ix.netcom.com>
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> 375 and Dave's Excellent Tube Adventure, Part One
> 
> OK... these two used 1625s are expendable so let's push this
> thing.
> But the beam plates are connected to the cathode inside.  
> Won't that keep it from working?  Who knows.... we'll find out.
> Change the bias?  No way.  Any irreversable circuit change 
> is absolutlely forbidden.  If it doesn't work, it doesn't work.
> 
> Time to mount the 1625 sockets in the 211 bases.
> Tie cathode to pin 7.... 
> Plate lead with parasitic choke to screen on pin 3.
> Grid to pin 4..... man, that's close to the plate lead.
> Better dress that as far away in the 211 base as possible....
> There!  Two of them ready to go.  
> 
> First- I'll tune-up the rig on 3890 KC with the 211s so 
> I'll be somewhere close.  70 Watts out.  Good.
> Off with the power and in with the 1625s.
> My primary supply is 27 volts... Switch the Primary Source switch
> inside the rig to "24" Volts and, since the fil current is
> different,
> that gives me something close to the 12 volts.  Nice, red heaters!
> 
> (Angle on my sholder; "But that's 1000 Volts on the plates, boy!")
> Hmph, David!  Is you a man or is you a mouse?
> Go for the gusto!   
> If it blows-up, you can do like a government contractor;  Hide it!
> ........(cring...)   *CLICK!*......  70 watts out.
> (un-Click)...... hmmmm......
> *CLICK!*...... 70 watts out.   No red plates.  
> No smoke.  No fireworks.   Hmmm!  
> 
> OK.... OK.... Let's see about neutralizing.
> Switched to "voice" (Angel on my sholder: 
> "Wait you dummy!  Don't you know about
> plate modulation??  You're really pushing your luck!").
> 
> "Fortune favors the foolish!"  *CLICK!*
> ...... (whisper...)  "hello? hello test?"  Audio,
> but FMing, of course.  Needs to be neutralized.
> "Hello hello..." (fiddle fiddle...)  "hello hellooooo"
> (fiddle fiddle fiddle) .... getting "cocky"...
> "hellloooooo HELLOOOOOO....HELL.." "**BOOOM!!**"
> (flash flash sizzle sizzle.... as one 1625 takes wing to Tube
> Heaven...).
> 
> ummm.... so.... I guess I should write this up and tell everyone
> how it's gone so far, right?   
> Even if it does make me look like a DOOFUSS, right??
> 
> Naaaaaaaaaaaa!
> 
> 73 OM DE Dave AB5S
> 
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