My "Stupendous" PPP 6P1P build

[Bas Horneman]

To avoid soiling kodabmx'S thread. I'm showing my build progress here. Starting with the psu that was done. The naked caps are BC 680uF...I do not like the look of the blue caps that's why I ripped off the plastic. I could have gotten all 680uF but thought getting a different type with different value would be a nice touch...I'll never know. Its a 120uF.

 

[Bas Horneman]

Chassis is from my local Action. Europeans might know the store. 9 odd euro's.
Ordered some aluminium. Most drilling done. The rest of the drilling once all the parts come in.

 

[Bas Horneman]

This was the inspiration for using the bamboo.

 

[zintolo]

Thanks Bas!
Is the thermal reflective tape properly working?
What is the dissipated power on that resistor?

 

[Bas Horneman]

Is the thermal reflective tape properly working?
What is the dissipated power on that resistor?

It should do. Can withstand 450 degrees Celsius, reflects 80% of radiant heat.

Resistor only 4 Watt max. So not really needed. But since I have the tape I decided to use it.

 

[Bas Horneman]

I'll also be using the "little" ones. Probably for power transformer and output transformer...hopefully. And then stick them all together for a U shaped amp.

 

[Bas Horneman]

Main pcb's almost done.

 

[Bas Horneman]

Heater supplies 12V/2A in the house.

 

[kodabmx]

Lemme know how those heatsinks work for you. I'm using bigger ones and they get nice and hot, but I don't ventilate my chassis.

Also let me know if those puny little heater supplies will start into cold heaters - I bet they won't.

I'm using one of these for all 18 tubes in mine - starts up immediately too...
AC 100 260V to DC 12V 13A 150W switching power supply module AC DC|Replacement Parts & Accessories| - AliExpress

 

[Lingwendil]

Nice work on the chassis so far!

 

[Bas Horneman]

Also let me know if those puny little heater supplies will start into cold heaters - I bet they won't.

If they don't I've got 12v/5A switching as a backup.

 

[Bas Horneman]

I'm using bigger ones and they get nice and hot

Now I'm getting a little worried. Since the lm317's I got were these thin ones...so not a tight fit in those heatsinks.

On the other hand....I did not realize that you need them at all for 38mA.

 

[Bas Horneman]

Nice work on the chassis so far!

Thanks!

 

[kodabmx]

On average, they will drop about 16 volts. That works out to about 600mW dissipation for the LM317. Should be fine and LM317 has protection built in... just saying if it acts funny, they might be getting too hot. The chassis temperature of mine is about 75°C so I can only imagine how hot they get inside it.
TBH I was thinking of the TL783 I use in the Little Miracle amp with 6P43P... They eat over 1W in that design.

 

[rotaspec]

You could switch to a LT1083 as a reg. Much beefier than LM317.

 

[kodabmx]

Great for a regulator, but completely overkill for a 40mA CCS.
There's also LM338 but no need.

 

[Bas Horneman]

Also let me know if those puny little heater supplies will start into cold heaters - I bet they won't.

You would have lost that bet!

 

[kodabmx]

Impressive. Did it have to try and start up several times?

 

[Bas Horneman]

Did a quick check. I suppose it does try several times. Because I saw the led turn on and off about three times. I'll wait till they are cold again ....and re-try.

 

[Bas Horneman]

7 flashes before the led stayed on...