F5m kit

[rolandong]

Is this balanced F5m correct?

 

[chermann]

if you want to make a PCB ....signal Ground is missing

 

[Mikerodrig27]

Is this balanced F5m correct?

Very curious about this. Imagine little 3U or 4U monoblocks.

 

[WBS]

I have imagined them. And Digital-Do-Main pretty much nailed the design IMHO. 🙂

 

[rolandong]

Breaking News, bunch of F5m kit goodies bound to store has been held hostage by hothi pirates😆🤣😆

 

[6L6]

Oh no!!

 

[HeyBill]

Where is my cruise missle when I need it.

 

[Zen Mod]

Breaking News,

you know drek

they're sidelined to OPLDF

 

[BeardyWan]

`...held hostage to Houthi pirates'

So not a shipment with any ties to China....

 

[Toys4Boys]

Any update on the chassis?

 

[r66cort]

Not-quite-the-build-guide configuration, but pretty close. This isn't the final PSU board, (there was a rev needed) and I need to re-code the wiring colors instead of use what I can dig out of my drawers, get everything squared up and dressed a little prettier.

It works great and sounds beguiling, this is going to be a popular build.

😎

View attachment 1269746

View attachment 1269747

View attachment 1269748


(And for those interested, it's an Omega bracket from Toroid of Maryland. https://toroid.com/omega-bracket-vertical-mount/ )

Trying to sort out PCB sizing for the F5m and associated PS to see if I can frankenchassis with some on-hand parts. From @6L6's images using UMS heatsinks we see the F5M bolt hole centers at 80mm x 40mm, with an additional 20mm for each transistor. Is that correct? Regarding the sizing of the DIY Bipolar PS Board, using the capacitor drawings on the PCB (30mm? EPCOS B41231B7478 shown is 25mm ) it looks to be around +/-150mm x +/-120mm total? Interested in thoughts or proper measurements. Thank you!

(Big thanks to 6L6 for the reference images, as well!)

 

[Thypils]

A perhaps naive question: The transistors must be isolated from the heatsinks - right?

NB: Is there any news about the hostage situation in the Red Sea?

 

[MatthiasMuc951]

I would say attached so that they can transfer the heat into the heatsinks. Isolated wouldn't make sense at all.

Disclaimer: I'm neither a native speaker nor have I finished a single amp project, so there are risks to this. ;-)

Also looking forward when the kits have arrived to the store.

 

[andynor]

Well, HAVE to be is a relative question. But yes, they should. Only the fearlessest of the fearless dare not isolate them (MZM)

 

[Dennis Hui]

Yes, the output transistors need to be electrically isolated from the heatsink but thermally coupled to it. When time time comes to order, consider also getting some of these most excellent Keratherm pads:

https://diyaudiostore.com/collections/consumables/products/keratherm-transistor-insulators

 

[Thypils]

Yes - I meant electrically insulated - sorry...
(In Danish, we only have the same word for electrical, thermal, geographical, social, etc., isolation/insulation.)

 

[Thypils]

When time time comes to order, consider also getting some of the most excellent Keratherm pads:

Yes, I've looked at them - but there are only seven sets left in the store - so I don't expect to be lucky enough for there to be any any left once the F5m kit arrives... 😥😥.

In dark moments, I'm even fearing that the kits will be sold out before I have had the chance to order one, given the headstart you have on your side of the big pool west of here...😭😭.

 

[andynor]

I wouldn’t worry too much about stock. The store seems to restock them regularly. But you can get them from other sources as well, I think. Saw them on Conrad a while ago.

 

[Peppe]

You only need four. I will send you if they are out of stock. Just buy the kit. 😉

 

[WBS]

The completion kit to be offered in the store includes 4 very thin insulators, silicone I think, that are efficient at transferring heat.