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In Reply to: RE: Quickie done quick (with errata) posted by vanofmonks on September 27, 2009 at 08:57:40
Looks great, nice and simple... I ordered two kits, partly because of the 10% "two-fer" price redcution, but mainly since I wanted to build one up as stock, and the other one as the experimental guinea-pig "Franken-Quickie".
One thing I notice in the photo, usng insulated RCA jacks on a non-conductive chassis plate is kinda like wearing both belt and suspenders ;-) Butr then, Franken-Quickie will mostly get built up on a cast metal box, so they would be needed.
I know, I'm jumping the gun a bit here, but please be patient with me ;-)
Just thinking, if the "cathode" to grid voltage differential happens to fall within normal LED operating voltage ranges, would using LED "bias" instead of the standard paralleled resistor and cap, be a good mod?
That would also solve the pilot light question, at the same time.
/ed B in NC
real radios glow in the dark
Follow Ups:
Hey, it's cheap - give it a try!
The normal cathode resistor is 1K with 2mA current, so 2 volts with fresh batteries. A normal red LED is around 1.8 volts, so that looks good. The fixed voltage means the bias won't decrease when the battery voltage falls. On the one hand the battery current will reduce faster as the battery runs down (longer life), on the other hand the tube's operating point will wander off optimum more quickly as the battery voltage falls (shorter life). No idea which trend will win out...
IIRC, the amber or yellow LEDs run closer to 2VDC, as do the old "slime green" ones (the newer type "true" green are around 3.2V).
It will be an interesting experiment.
The local stupermarket was selling Duracell 9V batts at a whopping $5.98 each, I think I'll bulk order some "no-name" 9Vs from C. Crane, or look for bargains at "the shack"
/ed B in NC
real radios glow in the dark
If you have a Fred's dollar store close by you can purchase Panasonics for $1.99 ea with the D cells being $1.99 for 2. - total $10.87 with tax!
The Fred's in Hayesville, NC just closed, allegedly because of an issue with their landlord, and with their lease. There are two other Fred's in nearby Hiawassee GA, and Andrews NC.
Definitely a better sounding price for batteries, than at the Ingle's supermarket!
/ed B in NC
real radios glow in the dark
I've been through Murphy/Haysville several times. I'm originally from Cleveland, TN and now reside in Nashville and Sewanee TN but return to Cleveland to visit family. It would be great to get some fellow Bottleheads sometime!
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