I need the ones with the hole for the IRFP240.
I could also be willing to order them from the diyaudio shop if somebody wants the other 6 pieces or at least 4 of them.
I could also be willing to order them from the diyaudio shop if somebody wants the other 6 pieces or at least 4 of them.
I haven't done the math. How many square centimeters are needed for four IRFP240s?
Price for that amount shipped in the U.S.?
Thanks...
Keratherm, yes. Heatsink, no. (Sorry, I'm totally used to this question being about heatsink required...)
To quote Papa - (from F5 manual)
In Metric,
8" = 20cm
6" = 15cm
300cm^2 per device, and the heatsink has 5cm fins.
To quote Papa - (from F5 manual)
So that's 48in^2 per device, and that 48in^2 has 2inch fins.
In Metric,
8" = 20cm
6" = 15cm
300cm^2 per device, and the heatsink has 5cm fins.
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Mica transistor isolation pads! I think your talking H.S.s 😀
Well, forget that. page was old or I was behind
Well, forget that. page was old or I was behind
After this comment from Mr Pass I knew I must look elsewhere for my "tad of brightness" in my horn system. Who am I to question the master of amplifier design and if he says the amplifier is not bright it must not be. Horns have a tendency to be bright so that is where I looked. After changing the crossover some more and lowering the attenuation of the mid range range driver approximately 3db I have found audio bliss. I was listening with a SE BA3 amplifier with 3 output stages before the F6 and was happy with the sound. The F6 showed so much more detail revealing flaws in my total system that had to be upgraded. This happens when a better piece of equipment is placed in your system. The F6 reveals the most detail, soundstage and bottom end that I have had in my system. I look forward to building a V-fet amplifier to see how much better my system can sound.
Thank you Mr Pass for setting me on the right path.
Before your comment I was swapping back and forth with the BA3 and F6. The BA3 sounds very very good with my speakers but when I placed the F6 back in my system is was obviously more revealing and for lack of a better word "clearer sounding".
After listening to my Feastrex D9nf's (still have them) with the F5, I said
"Sounds like instant coffee in a microwave oven".
😎
*credit to Steven Wright, comedian: "I put instant coffee in a microwave oven
and went back in time."
Hi to all, my F6 did't turn on yesterday. The fuse blew up. So I cut the supply wires to the boards (no load) and checked again: another fuse blow. The trasfo and rectifier are okay, one channel psu is okay but the other one is out of order, I presume a short into some cap.
Everything seem okay, no signs of burning or whatever, the IRFP240 looks good. I think I shorted the output of that channel and my question is: is it possible that I have damaged just the psu cap?
-Alex
Sent from my iPhone using Tapatalk
Everything seem okay, no signs of burning or whatever, the IRFP240 looks good. I think I shorted the output of that channel and my question is: is it possible that I have damaged just the psu cap?
-Alex
Sent from my iPhone using Tapatalk
Hi Zen Mod, yup means yes? I don't think that the F6 has some protection against output short, doesn't it?
-Alex
Sent from my iPhone using Tapatalk
-Alex
Sent from my iPhone using Tapatalk
yup, yup means yes 
no protection , but there was not need for that , if you didn't put any load on output
sort PSU and proceed , taking care of starting trimpot position (all way down to source level , in both cases )
no protection , but there was not need for that , if you didn't put any load on output
sort PSU and proceed , taking care of starting trimpot position (all way down to source level , in both cases )
😀 Thank you!
Yes, the short was done with the speaker disconnected;
It's my dog's fault! He likes gnawing my right speaker's cables so I have to
disconnect every time and sometimes I power the amp before connecting theme...😱
Yes, the short was done with the speaker disconnected;
It's my dog's fault! He likes gnawing my right speaker's cables so I have to
disconnect every time and sometimes I power the amp before connecting theme...😱
sorry , I re-read your post more carefully now
check mosfets at least with diode test , to check for shorts
back up pots all way down (minimum current) then repeat entire setting procedure , observing currents (voltage on both source resistors) and output offset
check source resistors too , prior to powering up
check mosfets at least with diode test , to check for shorts
back up pots all way down (minimum current) then repeat entire setting procedure , observing currents (voltage on both source resistors) and output offset
check source resistors too , prior to powering up