F5 Turbo Builders Thread

[tinitus]

that said, I think the original BA-1/2 idea by Nelson kind of opened the door to using two heatsink per mono amp
negative and positive side on each their seperate heatsink
or at least it looked that way to me
DC drift problems ? ....dont know

 

[AudioSan]

maybe also focus on good venting of the box itself

it would be possible to make it work in unity with heatsink convection
difficult with a standard box design

but might work well if lifting the lid up using print board stands

imo...not sure I would like to mess with anything that wouldnt work with 'normal' heatsinking....whatever normal is

i'm going to use 10mm PCB spacers between the sinks on top lid
well. normal heatsinking? it's no such thing in class A world

 

[AudioSan]

that said, I think the original BA-1/2 idea by Nelson kind of opened the door to using two heatsink per mono amp
negative and positive side on each their seperate heatsink
or at least it looked that way to me
DC drift problems ? ....dont know

thats what i'm going for on my v3 mono's.

 

[Rixsta]

those who built the F5T what was your main reason ?
Did you realy feel like the 25w version was not enough ? and why ?

Thanks

 

[AudioSan]

just to try it. and that i allready had a lot of parts for it. like transformers, caps, heatsinks+++

 

[Rixsta]

Thanks, yeah ive got a few transformers lying around that i probably wont need, one or two for the Zen4.

So just to sum up, for F5T (v2)
those of us using modushop.biz chassis, we need atleast the 5U - 400mm ?

i'm going to use 10mm PCB spacers between the sinks on top lid
well. normal heatsinking? it's no such thing in class A world

That sounds good, maybe a kind of wire see thru mesh would be good for the lid, i always like to see inside lol and make it pretty with LED's inside haha

 

[Rixsta]

Marching on have found my next issue, the non-existant output transistors FQA12P20, FQA19N20.

Best alternative for F5Tv2 ? are the Irf/irfp pair usable ? they are quite expensive too, i guess any transistor like this is.

 

[AudioSan]

i would go for 5U 500mm.
the irfp part are easy to come by, and cheap. the also work great.

 

[BigE]

I made this simple circuit on startup, is simple and works great.

That circuit is for the primary side/transformer startup only. It also has a VA rating limit.

 

[Rixsta]

you can get the sj74/sk170 pairs from some members here. Spencer among others.
rest of the parts you can get from mouser, if you og for irfp240/9240 outputs. but remember. they will need matching. you can also get those fets matched from another member here, h_a.

you mean that like the IRF mosfets need matching but some of the othrers don't ?

 

[WalterW]

No, you can get them unmatched at Digikey, Mousser and so on, but for matched pairs you have to contact h_a

 

[AudioSan]

you mean that like the IRF mosfets need matching but some of the othrers don't ?

no. they will all need matching.

 

[a.wayne]

Has anyone seen Buzz ..?

 

[Zen Mod]

he's buzzing at super speed , so hard to spot

but , be sure he's around

 

[jacco vermeulen]

Has anyone seen Buzz ..?

I saw various bits and pieces, after hitting it with a swatter.

 

[buzzforb]

I am trying to work here.

 

[a.wayne]

One silicon blob at a time ....

 

[SteveHolt]

Hello

Almost finished my F5 project, just wanted to check before I turned the power on...I have connected together the gate and source pins on both Q3 and Q4, is this correct?

 

[6L6]

???







What?

That doesn't sound correct, can you elaborate what you mean? And photos would also help.

 

[oiphy]

that sounds wrong.....