These photos were taken at the time of build and all measured well and stable. I did run on the bench to .5v bias which as you can see is drawing 2.3amps per rail this is at 32vdc as I remember:- just to see.
Square wave was good too..1v input at 10k
I was very happy and ended running the amp at 250mv of bias well below a recommended 300mv....by members.
Doesn't the instruction say to set bias with the amp closed in order to get the proper temperature equilibrium?
Doesn't the instruction say to set bias with the amp closed in order to get the proper temperature equilibrium?
Yes..very important. Lid on. The photo was only to show my build and test of the circuits, not the final setup...
I would start and set the bias to 100mv, drop the lid and leave for 1 hour then check bias and offset again and re adjust bias to 150mv drop the lid and leave again for an hour.
After this time the temp is rising on the sinks and the bias is rising with it...possibly pushing 200mv. Re adjust bias to 225mv and lid back on leave for 15-30mins re check bias 'may be' over 250mv, so wind back the bias to below 250mv say 225mv, again lid back on and wait again, re adjust until a 'steady state' of 250mv bias and near 0mv offset as possible. I can normally get within 1.0mv offset. which is very good...
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hi2 all
will be pair (one per channel) this inductors good for CLC filtering in F5 (not turbo) power supply? 400VA 18+18
thank you
Rhombus L-522-08 Toroidal Transformer/ Inductor DC/DC Power Supply, 2mH 10A | eBay
will be pair (one per channel) this inductors good for CLC filtering in F5 (not turbo) power supply? 400VA 18+18
thank you
Rhombus L-522-08 Toroidal Transformer/ Inductor DC/DC Power Supply, 2mH 10A | eBay
nope
what you need is either big air core inductor or also biggish iron core inductor
that one is for AC
thank you! so, I need something like this? Air Core Inductor Crossover Coils in the Speaker Components Department at Parts Express | 297
what power handling needed is 300 Watt per rail is enough?
seems it will be a good choice?
Brand New Hammond 195G10 Dc Reactor Choke 5Mh 10A | eBay
cant find air core with small resistance
Brand New Hammond 195G10 Dc Reactor Choke 5Mh 10A | eBay
cant find air core with small resistance
psu v3 ?
hello, i saw here ( Stereo F5 Turbo V3 ) a realization of F5 v3 that on the psu uses 4x37v trsformator .. but did not have to be 2x24v as in v2?
hello, i saw here ( Stereo F5 Turbo V3 ) a realization of F5 v3 that on the psu uses 4x37v trsformator .. but did not have to be 2x24v as in v2?
read this , few months minimum : http://www.firstwatt.com/pdf/art_f5_turbo.pdf
then , go back with questions
then , go back with questions
thanks. going to order PCB form Jim's
Heavy duty power supply partial kit Pass amplifiers ! | eBay
Heavy duty power supply partial kit Pass amplifiers ! | eBay
I'd use his other board:
Power supply PCB for DIY First Watt class A Power amplifiers ! | eBay
with some off-board bridge rectifiers:
GBPC3504 ON Semiconductor / Fairchild | Mouser Ireland
Rectifiers are somewhat noisy, so I like having them as far away from the input signals as possible. (See the insides of a production F5.) Having them bolt to the chassis bottom also keeps them much cooler.
Either will work, though.
Power supply PCB for DIY First Watt class A Power amplifiers ! | eBay
with some off-board bridge rectifiers:
GBPC3504 ON Semiconductor / Fairchild | Mouser Ireland
Rectifiers are somewhat noisy, so I like having them as far away from the input signals as possible. (See the insides of a production F5.) Having them bolt to the chassis bottom also keeps them much cooler.
Either will work, though.
Keep the charging circuit from transformer secondary through rectifiers to main smoothing capacitors SHORT and COMPACT. Minimise LOOP AREA to reduce interference emitted to other circuits...............with some off-board bridge rectifiers:
.....................
Rectifiers are somewhat noisy, so I like having them as far away from the input signals as possible. (See the insides of a production F5.) Having them bolt to the chassis bottom also keeps them much cooler..............
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