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November 30, 2021, 01:27:40 PM

Author Topic: PJCCS quickie v1.0 vs. v1.1 question  (Read 82 times)

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Offline fshmstr

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PJCCS quickie v1.0 vs. v1.1 question
« on: November 05, 2021, 08:46:46 AM »
I have quickie v1.0 assembled via updated manual with tube pin 5 connected to negative heater supply and pin1/7 to positive heater supply. (also bias resistor/bypass cap pin 7 to ground, contrary to schematic which shows bias resistor/bypass cap connected from pin 5 to ground [thus voltage pin 5~1.3v and voltage pin 1/7~2.6v]). I have ordered but not yet built the PJCCS. Why does the PJCCS v1.0 omit the 2n2222 and just send R2 to ground? Is there an advantage to having the 2n2222 and/or penalty for it's omission. Quickie v1.0 and v1.1 is the same circuit just different lay out, no?
Ralph Miyashiro

Offline Paul Birkeland

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Re: PJCCS quickie v1.0 vs. v1.1 question
« Reply #1 on: November 05, 2021, 08:54:11 AM »
The Quickie 1.0 used a three gang power switch to switch both the filament supplies and the B+ supply.  It has been a while and I can't remember back then if I wanted to switch the B+ because I was concerned about a possible C4S upgrade, or if it just didn't occur to me at the time that cold tubes don't draw any current and a battery power supply doesn't have a bleeder resistor. 

Quickie 1.1 used a combination selector switch and power switch that just powers up the filaments and leaves the B+ permanently going.  I thought this was really cool when we did it, but then it made the current source upgrade a bit more complicated, as it needs to sense when the filaments are drawing current and then allow the CCS to do its thing.

So to answer your question, the circuits are very different.  If you want to use the 2N2222 equipped version on a V 1.0 Quickie, that would be a lot more trouble than it's worth!
Paul "PB" Birkeland

Bottlehead Grunt & The Repro Man

Offline fshmstr

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Re: PJCCS quickie v1.0 vs. v1.1 question
« Reply #2 on: November 05, 2021, 10:23:46 AM »
I damaged my three pole DT switch so wired my Quickie v1.0 with only the filament supply switched and B+ always on(since manual states no current draw with cold filaments). In light of this should I treat my Quickie v1.0 as v1.1 and include the 2n2222 in PJCCS circuit?
Ralph Miyashiro

Offline Paul Birkeland

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Re: PJCCS quickie v1.0 vs. v1.1 question
« Reply #3 on: November 05, 2021, 10:37:42 AM »
I would replace the original power switch to also switch the B+ and use the PJCCS for version 1 of the circuit.
Paul "PB" Birkeland

Bottlehead Grunt & The Repro Man