L'Amp: A simple SIT Amp

[CanAm Man]

make it 1800VA per channel

Sacre bleu...! Mon Dieu....!!

 

[jkchoi]

How about this?

Will it work?

 

[juanitox]

finally i will build a fig 9 with the source degeneration and 47000 bypass cap. i have found the Bulb, the VFEt, the Caps, power supply, but i can't found big heatsink for TO3 . do you have a source for big heatsink ? any model?

i can wait begining the little monster

 

[juanitox]

fig11 for me sorry

 

[Michael Rothacher]

The heat sinks I used were either Wakefiled or Thermalloy. I got them surplus already drilled for TO-3 and they're no longer available from surplussales.com.

Another option is shown in Post #15.

The heatsink pictured is Aavid DB180-20 available from Newark / Farnell.

 

[juanitox]

thanks michael , i have just found that i 'v got big fanless cpu heatskink to try also they are rated 65W .. i will try this on the top of the TO3 with mica . i have seen the Pass had tried to swap the 10000uf CAp with a 1000uf MKP and get 30hz . do you think with 1800uf i could get 20hz?

 

[Michael Rothacher]

I seriously doubt that a CPU heatsink is going to work well here. I don't recommend dinky heatsinks (fans or not). See my first post in this thread where it says "Don't skimp here". You've been warned.

This project is best built according to the author's specifications. That's why he invested the time and effort to write it; so you wouldn't have to learn too many things the hard way.

I provided you with a calulation, so you could find the low frequency cutoff and response with any capacitor you like.

 

[Zen Mod]

I tried

it poofed

I'm dumber than Author ......... he is in conspiracy with bloody DiyA administration !

 

[juanitox]

sorry , i was lost , the wine perhaps... i have found a more suitable one on farnel :AAVID THERMALLOY - NV115-1

An externally hosted image should be here but it was not working when we last tested it.

 

[Michael Rothacher]

That may work. The center, which is almost 1/2" thick, may require some machining to accept the TO-3 though.

 

[Nelson Pass]

This would be a fit: 2SK77B

 

[Michael Rothacher]

Sorry, was I slobbering just now?

 

[Roscoe Primrose]

Well, I picked up a quad of KD33s today at the post office... Let the 1:1 transformer build begin ;-)

Roscoe

 

[Michael Rothacher]

We just had a power sag in my neighborhood. Was that you, Roscoe?

 

[Zen Mod]

nope

it was me , making plasma of some Cal's Altecs

 

[Michael Rothacher]

Be careful not to pass out from ozone.

 

[Roscoe Primrose]

It'll probably be tomorrow night at the earliest before I can get to it, working late tonight. Have to finish up the F5 which is Dad's Christmas present as well...

Roscoe

 

[PSz.]

Roscoe,

How big are those 1:1 transformers? Where did you get them?

 

[Roscoe Primrose]

The ones I'm using now I hand-wound on cores/bobbins from Hammond 1628SE (now 1628SEA) transformers (about 11lbs each)... It's a quadfilar wound transformer with 16ga magnet wire, using 2 windings in parallel for the primary and secondary.

I've asked Edcor (today) about making some, but haven't received a response yet.

Roscoe

 

[Michael Rothacher]

Have to finish up the F5 which is Dad's Christmas present as well...

A nice present.

Show us a pic of that transformer if you get the chance.