Hi
I cleaning the copper I sprayed 3 coats of Incralac using a 1.7mm nozzle waited 30+minutes between coats .
Incralac is a clear vanish designed for copper & copper alloy's .The surface fills like glass .There was no need to rub down between coats .
http://www.wattyl.com.au/library/TDS/Incralac.PDF
Cheers
Other words it is Loftin-White schematic.
EF860 is pentode connected.
A voltage of the second grid is a steady-state by voltage regulator. I can regulate the plate current of output tube by this voltage regulator.
Here's an amplifier that I just finished. Its a 2V red LED biased 12sl7 split-load phase splitter, and a 6as7g garter-biased output stage. Power is from a toroidal isolation transformer with added heater windings.330V B+ (center tapped). The Input stage runs across the supply, the output stage gets a B+ of 165V from the PSU center tap. The output stage has a garter bias scheme, 330 ohms each resistor, with the cathodes connected through a 150uF non-polar electrolytic. 90V across each 6as7g, 30V across each R, and 10v lost in the transformer. Sounds very nice, and has very nice bass even with cheap speakers. Also pictured is my passive preamplifier, a basic 100k pot with basic RCA in/out, and a switching 1/8th input on the front.
Yup, I like the different approaches to casing, I'm a little bored of the "wood box with a metal plate" approach to casing. Also, one Big hole is easier than a BUNCH of little ones.
Hi,
this is my first posting in this forum. What I am showing here is "work in progress": a triode headphone amp based on Kurt Strain's design ( HeadWize - Project: An OTL Tube Headphone Amplifier by Kurt Strain ). I made the enclosure from 1/16'' aluminum sheet. Due to an issue with hum I will relocate the power supply to a separate enclosure.
Warm regards,
Fred
this is my first posting in this forum. What I am showing here is "work in progress": a triode headphone amp based on Kurt Strain's design ( HeadWize - Project: An OTL Tube Headphone Amplifier by Kurt Strain ). I made the enclosure from 1/16'' aluminum sheet. Due to an issue with hum I will relocate the power supply to a separate enclosure.
Warm regards,
Fred
Attachments
My latest creation. Class A, 3W per channel, single ended. Can be easily changed to pentode mode. I made this one for sale, but still not sold 
More info here: Forums - SE84C+ Review Tone Audio Magazine
More info here: Forums - SE84C+ Review Tone Audio MagazineAn externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
Thank you. I am professional.
Empty space on front part of chassis looks odd, but there I will hide digital controls of inputs and volume. 5 inputs remote controlled (relays), and motorized fader remotely controlled, that controls relays of ladder attenuator.
It is very simple: string of 2 Zeners, 120V each, in series, and couple of MOSFET followers, for 115 and 235V. Time constant for 15 S. Similar regulator for -40V, with very short time constant, and one for 6.3V using one MOSFET and one small BJT, with couple of LEDs for reference voltage. Excess 2.1V for 4P1L dropped by pair of 3 Ohm resistors per tube, one from each side. CTs of 4P1L filaments grounded. 6J5P and 6N16B filaments powered from regulated 6.3V.
Last edited:
Would never of thought of it but a good idea.
Any noise from the leds. They are meant to be noisy little devils.
Do we have postable schematic. I did a 12AX7/6AS7 SET. Just two tubes and rec tube. Love the amp-3W. Every one who listens to it wants one.
Love the finish.Forgive my ignorance, I would like to ask what exactly is "engine turned" I really like it, wow!