"Superfly" - submini tube version of Doug H's Firefly

[jsbull23]

Hey I was just wondering where the input jack and output jacks grounds go in the circuit. I have some experience with electronics but not much.

Thanks!

[jsbull23]

Hi all. What kind of power supply should I get for this project? I know it has to be 12 volts, but how many amps?

[bluebunny]

All the ground points in the circuit connect together, along with the ground lugs on the input and output jacks.  Rick says on page 1 that he was using a 500mA power supply (but a few pages on he's using 750mA).

[jsbull23]

Thanks for the help!

[rankot]

All image links are now dead, I would appreciate if someone can post original schematic again, and even better schematic for amp with glowing tubes.

[bluebunny]

[rankot]

Nice, thanks!

[bluebunny]

Added the Nixie power supply for you too.  (Hope Rick doesn't mind me re-posting this stuff.)

[rankot]

I had that supply, but thanks anyway! What is B+ voltage for this little amp?

[frequencycentral]

Rick doesn't mind at all, and is hoping to get the time to host some of his Photobucket/Dropbox lost content on his website someday soon. He's even working on a new phaser PCB for you.

[Scheissami]

Sorry to bump an old question, but looking to finally get this little amp working (having another kid definitely put a big freeze on my trouble shooting!).

Any suggestions are welcome. I'm to the point where I may just pull everything salvageable and try to build it on project board rather than trying to etch another ghetto home-brew PCB.

Cheers.

Hi, guys, I need some help debugging my build. Spent a lot of time on this thread, read all of the little hints and suggestions but still don't have a working amp. I'm using the PCB layout, with added Tone, Bias, and MV controls.

When I plugged in my power supply (center positive but I wired appropriately) and flipped the power switch, my LED lit up, and I immediately got 12V at the center tap. The tubes' heaters began to glow, and I figured in a couple of seconds I'd see the voltage start to climb. Then, nothing. LED goes off, voltage drops. No smoke, crackles, sizzles, pops.

I went over everything I could think of, including checking the tracing for solder bridges or other shorts in the wiring. I think the tube polarity is correct (gap towards the NE555, right?). The VR was a little bent after getting it to fit, so I replaced that: no change. I also swapped out the BC547 transistor (I had socketed per FC's suggestion) as well as the NE555 without any change. When adding the tonestack, I omitted both R16 and C8. I didn't bridge the gap left by the absence of C8 (reading the updated schematic, none of the remaining connections went to ground), I figured trying that without a filter cap would only potentially fry more components.

What would be the other potential culprit components to check? I've built a few pedals and tube amplifiers so this isn't completely new to me, however problem solving beyond the simple stuff is over my head.

Thanks for any ideas!


https://www.dropbox.com/s/9iv6es4ydmxf5v0/IMG_3827.jpg?dl=0

https://www.dropbox.com/s/bivgp8l4l7ups1w/IMG_3830.jpg?dl=0

https://www.dropbox.com/s/r2vjbmdru9a0k6l/IMG_3828.jpg?dl=0

(Sorry, I had originally included the pics in my post, but they were massive and I wasn't sure how to resize them in dropbox...)

[bluebunny]

Rick doesn't mind at all, and is hoping to get the time to host some of his Photobucket/Dropbox lost content on his website someday soon. He's even working on a new phaser PCB for you.

That would be very cool, Rick.  Like a fridge with shades on.   

[rankot]

Sorry to bump an old question, but looking to finally get this little amp working (having another kid definitely put a big freeze on my trouble shooting!).

Any suggestions are welcome. I'm to the point where I may just pull everything salvageable and try to build it on project board rather than trying to etch another ghetto home-brew PCB.

Cheers.

Hi, guys, I need some help debugging my build. Spent a lot of time on this thread, read all of the little hints and suggestions but still don't have a working amp. I'm using the PCB layout, with added Tone, Bias, and MV controls.

When I plugged in my power supply (center positive but I wired appropriately) and flipped the power switch, my LED lit up, and I immediately got 12V at the center tap. The tubes' heaters began to glow, and I figured in a couple of seconds I'd see the voltage start to climb. Then, nothing. LED goes off, voltage drops. No smoke, crackles, sizzles, pops.

I went over everything I could think of, including checking the tracing for solder bridges or other shorts in the wiring. I think the tube polarity is correct (gap towards the NE555, right?). The VR was a little bent after getting it to fit, so I replaced that: no change. I also swapped out the BC547 transistor (I had socketed per FC's suggestion) as well as the NE555 without any change. When adding the tonestack, I omitted both R16 and C8. I didn't bridge the gap left by the absence of C8 (reading the updated schematic, none of the remaining connections went to ground), I figured trying that without a filter cap would only potentially fry more components.

What would be the other potential culprit components to check? I've built a few pedals and tube amplifiers so this isn't completely new to me, however problem solving beyond the simple stuff is over my head.

Thanks for any ideas!


https://www.dropbox.com/s/9iv6es4ydmxf5v0/IMG_3827.jpg?dl=0

https://www.dropbox.com/s/bivgp8l4l7ups1w/IMG_3830.jpg?dl=0

https://www.dropbox.com/s/r2vjbmdru9a0k6l/IMG_3828.jpg?dl=0

(Sorry, I had originally included the pics in my post, but they were massive and I wasn't sure how to resize them in dropbox...)

You must find out where is the first point without power. So, power this up, take DMM and measure voltage from DC plug to NE555 and forward.

[Scheissami]

Okay, so based on the description the problem is most likely to be a problem with the power supply so focus my problem solving on the SMPS system, yes? This is my first time building this particular circuit so not sure what the most likely culprit components are, but I suspect I'm looking for a complete inability to pass voltage forward? Not sure if I understand enough about the circuit to know which parts of the circuit will be carrying what voltage.

It'll probably be a few days before I'll have a chance to sit down and test the circuit, I'll respond with my findings.

Thanks for your input!

[rankot]

You may try to disconnect tubes and see is there any power in the circuit or not.

[Marcos - Munky]

Does anybody have these images? Photobucket fix isn't working here.

https://www.diystompboxes.com/smfforum/index.php?topic=78302.msg704930#msg704930

[rankot]

That's the one I have:

[Marcos - Munky]

I have that one too. The one I'm looking for is the one with tone, master volume and bias mods.

[thomasha]

I have this one>



The bias mode is here>

[Marcos - Munky]

That's exactly what I was looking for! Thanks, Thomas.