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RE: Transformers

Hammond has a couple of high inductance, low current chokes which may be usable as suitable plate loads for the Quickie's 3S4s.

155C, 60H, 8 mA, DCR = 2750 ohms, about $14 each.

156C, 150H, 8 mA, DCR = 3700 ohms, about $15 each.

Since these are both below the nominal 4.02K plate resistor value, one could insert an LED in series between the B+ line and the choke's "hot" side, for a pilot light, or tube activity indicator. Depending on the LED color, it will introduce between 1.6 and 3.6VDC voltage drop, which is pretty much minimal. Don't connect the LED on the plate side, it could introduce some unwanted noise into the equation.

Now, these inductors aren't going to be of Magnequest quality, but at the cheap prices, they may be a good deal for this application, along with the SPECO matching trannies. I'd SWAG that 2.2 to 3.3 uF would be a good coupling cap value , into the reflected 4K ohms. Voltage rating could be as low as 100V, but I'd probably go with 250V (basically because I have lots of such caps in my stockpile).

This topic alone has intrigues me to the point that I put in an order for not just one, but two, Quickies ;-)

Being one who can never leave "well enough" alone, these Quickies are a very interesting and readily modifiable project, which I just can't resist.. A little research indicates that 1S4s can be used with a simple re-conenction of the filament leads (use pins 1 and 7, leave 5 open). Just becuzz....

All of this talk of "quickies" reminds me of a very old, rude joke involving a pastor and a nun, but since this is a polite family-oriented site, I won't post it here ;-)

/ed B in NC
real radios glow in the dark


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