"Work in progress, PP KT120 HI-END class A .🙂"
That's really a nice PCB! Until reading the dch53 comment I wasn't aware of those holes!
Where did you buy that print or is it your own design?
That's really a nice PCB! Until reading the dch53 comment I wasn't aware of those holes!
Where did you buy that print or is it your own design?
For those who might care: The schematic for this light bulb amp. There is no hum cancel pot - it was for the version I would remake this with. R19, C10, C9 delete. 1R 40W for inrush. It's indestructable!
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I also just learned that I can not source a replacement lightbulb. Thankfully, the 300W bulb only gets to half brightness on start up.
In theory, it'll last longer than me. In practice, something will fly across the house and break the bulb! 🙁
In theory, it'll last longer than me. In practice, something will fly across the house and break the bulb! 🙁
I changed the VA/PI/DR boards for the new version with optional LED bias for the input stage. This one has 12AV5GA (trioded) for output.
I also wiped off most of the dust 😛
That glow tube is STR75/60
Also shout out to Samsung... It's pretty dark in here, but this photo looks like it's daylight.
I also wiped off most of the dust 😛
That glow tube is STR75/60
Also shout out to Samsung... It's pretty dark in here, but this photo looks like it's daylight.
Did you have any trouble with oscillations? I’ve seen some folks try this tube and have to do some things to keep them in line.
No oscillations but since triode connection has a low mu, I'm not overly surprised.
Here's the working schematic:
And this is how you get 600V (or 640V unloaded) and 320V from 120V input:
Here's the working schematic:
And this is how you get 600V (or 640V unloaded) and 320V from 120V input:
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Hello,
I wanted to submit a couple of images of my last "umpteenth" OTL ampifier based on E88CC and 6N6P tubes. As for me, the great thing is that I found an online company that creates nice metal / bronze labels cheaply. In this case I could customize the project itself by giving a name..
I wanted to submit a couple of images of my last "umpteenth" OTL ampifier based on E88CC and 6N6P tubes. As for me, the great thing is that I found an online company that creates nice metal / bronze labels cheaply. In this case I could customize the project itself by giving a name..
Attachments
Dynaco ST70 upgrades.1. converted to 230vac power traffo, doubled the core stack, used graetz rectifier, 340 vac secondary, separate 40vac filament bias winding, replaced selenium rects with flatpacks.......
2. installed 5 way speaker binding posts
3. replaced RCA input jacks, installed volume controls
2. installed 5 way speaker binding posts
3. replaced RCA input jacks, installed volume controls
Attachments
Decided to try the 6P43P in a modular amp... So far so nice 🙂
This is a 6HJ5 single ended, triode wired amplifier inspired by the design of member famousmockingbird.
The driver stage for this is different from that design, I'm using a 6AG9 compactron configured as a Kimmel mu stage for the driver.
The driver stage for this is different from that design, I'm using a 6AG9 compactron configured as a Kimmel mu stage for the driver.
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So after running the 6P43P for 2 days, I'm surprised how much power they make. Almost as much as the sweep tubes.
Facebook says I posted this 11 years ago.
My first real tube preamp.
My first real tube preamp.
I just bought some 300W incandescent bulbs for a fixture in my garage that needs long neck bulbs, would these do?
https://www.amazon.com/Sylvania-157...9&sr=1-3-270ce31b-afa8-499f-878b-3bb461a9a5a6