...yeah, in regards to the amplifier circuits, but the PSUs of all the Firstwatt designs (except the F3 and one other that uses a 48v single supply) are essentially identical.
That said Mark's above link is awesome reading. Also, I'd never suggest running one of these amps without some kind of inrush suppression or soft-start.
That said Mark's above link is awesome reading. Also, I'd never suggest running one of these amps without some kind of inrush suppression or soft-start.
I have 2 F5 V3 monoblocks as well. I do have surge limiting in those. Each one has an 800va transformer. A single 400w transformer is a lot smaller load then the combined load of 4 F5s.
I feel the CL-60 slow start arrangement is a good thing to have. That said, I ran my dual mono F5 for years without anything more than plugging it in to start it, still runs well today. Of course some while back the CL-60 thingies were installed! (love those no longer available Panasonic caps, want to be nice to them.)
Russellc
Working slowly on my 1rst AJ board.
MY AJ transistor kit from the DIYStore contents are the same as quoted above.
While researching on how to tell the difference between the 5.1V and 6.1V without a test rig that I don't have components on hand to cobble together, discovered that's a moot point as it seems that neither is correct, and the proper value is 9.1V.
Read the thread before starting, but the correct zener diode voltage posts didn't stick. Guess I skimmed over them, perhaps thinking "No sweat here, the zener's are in my transistor kit."
Forgive me a bit of a rant, but I finally get some time set aside to get the assembly of my AJ's going, hopefully to conclusion, then find this niggling detail was overlooked. Grrrr
Patience, grasshopper, just finish stuffing the board to make sure you've got everything before making another mouser order.
The BOM, linked to in Post #1, clearly states that a 9V1 Zener should be used, with a manufacturer part number and Mouser stock number.
Not sure where the 5.1V and 6.1V came in.
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I ran into this problem when I built my Aleph. I ordered the 9V1 zener from Mouser, along with all the other passive parts, but when stuffing the PCB I installed the zeners that came with the Aleph J transistor kit, which was either a 5V1 or a 6V1 part. Needless to say it threw off bias/offset and led to a lot of frustrating troubleshooting.
It wasn't until I was looking at the parts carefully and thankfully saw the parts list slip did the problem resolve itself; noticing the stuffed zener size and leads were smaller than the one in the build guide.
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I'm connecting speaker , or any load in fact , only when I'm positive that everything is ....... positive 
so , for all testings - inputs shorted , no load on output
then , if you prefer some real load testing , under condition that you know how and you have necessary hardware - use dummy load on output ...... at least 50W , 8R battery of resistors (goldie ones in Al case are dirt cheap nowadays on fleabay)
and then - some test speaker , shorted inputs , to test humbuzbangzzzzzzz , hoping for lack of it
put some signal on input ...... and if all is OK , time for proper speakers
so , for all testings - inputs shorted , no load on output
then , if you prefer some real load testing , under condition that you know how and you have necessary hardware - use dummy load on output ...... at least 50W , 8R battery of resistors (goldie ones in Al case are dirt cheap nowadays on fleabay)
and then - some test speaker , shorted inputs , to test humbuzbangzzzzzzz , hoping for lack of it
put some signal on input ...... and if all is OK , time for proper speakers