New project stuff maybe?

For those still waiting on your revised boards and boxes, I have all the boxes milled and powdercoated, but I'm still fighting to get my printer to print well enough. It's still very high up on my list of priorities and I am actively working on getting it resolved.
 
cris_mas said:
What about a drill template? i was waiting for this, since i think it will be a bit expensive to import an enclosure :/
Click to expand...
I have a Tayda drill template, but first of all it needs the FX send/return jacks moved, and secondly Tayda's 1590DD enclosures are too thick to use without counterboring. I will work on getting a pdf drill template though, for those that are adventurous enough to try it themselves.
 
vigilante398 said:
EDIT: with all the LEDs on it's pulling 855mA on a 9.4V supply. While the tubes were warming up it spiked around 1.7A (it's a benchtop supply with a lot of headroom for current), but you can probably get away with 1A or so.
Click to expand...
so, i have a very basic DIY power supply that runs off a mains transformer with a 1A AC current rating:
1707700483068.png
(12VAC taps --> bridge rectifier -> filter caps etc. -> L7812 -> filter cap -> L7809 + filter cap)

the voltage regulators are rated at nominally 1A, but datasheet(s) indicates can peak higher?
1707700764199.png

(it would be my preference to run these projects on the 12VDC supply, rather than 9V)

so looks like it should handle the idle current.
but I'm concerned about that 1.7A peak. will it fry my transformer?

just curious, have you measured the current pull with 12VDC supply? i wonder if the current pull at peak would be different vs 9VDC supply...

[9V x 1.7A = 15.3W (peak) : . 15.3/12V = 1.275A]
 
owlexifry said:
so, i have a very basic DIY power supply that runs off a mains transformer with a 1A AC current rating:
View attachment 68218
(12VAC taps --> bridge rectifier -> filter caps etc. -> L7812 -> filter cap -> L7809 + filter cap)

the voltage regulators are rated at nominally 1A, but datasheet(s) indicates can peak higher?
View attachment 68219

(it would be my preference to run these projects on the 12VDC supply, rather than 9V)

so looks like it should handle the idle current.
but I'm concerned about that 1.7A peak. will it fry my transformer?
Click to expand...
It would be more likely that the voltage would sag until the tubes heat up than that it would fry something. That's been my experience with most power supplies. If I limit the current lower on my benchtop supply then it still gets there eventually, but the voltage rail sags until the heaters get heated and the rail stabilizes.

owlexifry said:
just curious, have you measured the current pull with 12VDC supply? i wonder if the current pull at peak would be different vs 9VDC supply...

[9V x 1.7A = 15.3W (peak) : . 15.3/12V = 1.275A]
Click to expand...
That's not how tube heaters work, they are essentially an 84Ω resistor, so the higher the voltage you put into it, the higher the power dissipation, i.e.:

P = V²/R
P = 9²/84 = 964mA (theoretical steady state)

If we run a 12V supply:

P = V²/R
P = 12²/84 = 1714mA (theoretical steady state)

All of this is of course irrelevant because using a L7809 after L7812 means the 7812 is getting all the same current through it that the L7809 is, so you're going to start getting very warm. I would strongly recommend picking up something like a OneSpot if you're trying to run a Supersonic.
 
vigilante398 said:
It would be more likely that the voltage would sag until the tubes heat up than that it would fry something. That's been my experience with most power supplies. If I limit the current lower on my benchtop supply then it still gets there eventually, but the voltage rail sags until the heaters get heated and the rail stabilizes.


That's not how tube heaters work, they are essentially an 84Ω resistor, so the higher the voltage you put into it, the higher the power dissipation, i.e.:

P = V²/R
P = 9²/84 = 964mA (theoretical steady state)

If we run a 12V supply:

P = V²/R
P = 12²/84 = 1714mA (theoretical steady state)

All of this is of course irrelevant because using a L7809 after L7812 means the 7812 is getting all the same current through it that the L7809 is, so you're going to start getting very warm. I would strongly recommend picking up something like a OneSpot if you're trying to run a Supersonic.
Click to expand...
appreciate the response and correction.
i had a feeling my assumptions/calculations were all wrong 😶‍🌫️
 
Hello,

I would like to order a supersonic pcb and enclosure.
On c2c i can see "powdercoat and UV option is available only for the supersonic", but there is nowhere to select an option. I only can select supersonic (25$).

Does this mean that when i select supersonic (25$), the enclosure will be powdercoated and printed?
 
Creach said:
Hello,

I would like to order a supersonic pcb and enclosure.
On c2c i can see "powdercoat and UV option is available only for the supersonic", but there is nowhere to select an option. I only can select supersonic (25$).

Does this mean that when i select supersonic (25$), the enclosure will be powdercoated and printed?
Click to expand...
No, I'll have to get in and edit that. My UV printer died several months ago and I haven't gotten it fixed, so powdercoated and printed enclosures are not available.
 
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