Drivers bias with 220R is about 5mA, with 50R bias will be about 20mA before outputs start conducting.
fh11
hiii every one
i made fh11 with 3 pair irf640/irf9640
for bias use 2/2k multiturn
but 2n551's be hot ..what i do?
hiii every one
i made fh11 with 3 pair irf640/irf9640
for bias use 2/2k multiturn
but 2n551's be hot ..what i do?
hi i made this instead of 1kmulititurn insert 2k
and mje 350 be hot plz insert heat sink
and 2n5551 so be hot....what i do?
Inductor Help
I am putting together all the parts to build the FH11 (Mouser order came in today) so I'm trying to get everything laid out.
I am working on the inductor - which the silkscreen says should be 2.0uH, but other threads are from 1.0 - 2.0uH (how low is still ok?)
Questions - (using 16Ga 1.2mm enameled wire) I made two different diameter versions, both with 10-11 turns of wire:
- one around a pencil, approx 7mm internal diameter
- one around a AA battery, approx 11mm internal diameter
Pencil version measures 0.6uH (on left in pics)
AA battery version measures 1.6uH (on right in pics)
Which one should I use? I like the look of the pencil version since it fits the designated area on the board with out crowding surrounding components, but don't want to comprimise the quality just because of that.
I am putting together all the parts to build the FH11 (Mouser order came in today) so I'm trying to get everything laid out.
I am working on the inductor - which the silkscreen says should be 2.0uH, but other threads are from 1.0 - 2.0uH (how low is still ok?)
Questions - (using 16Ga 1.2mm enameled wire) I made two different diameter versions, both with 10-11 turns of wire:
- one around a pencil, approx 7mm internal diameter
- one around a AA battery, approx 11mm internal diameter
Pencil version measures 0.6uH (on left in pics)
AA battery version measures 1.6uH (on right in pics)
Which one should I use? I like the look of the pencil version since it fits the designated area on the board with out crowding surrounding components, but don't want to comprimise the quality just because of that.
Attachments
Sir,
Can you suggest a power supply other than Apex class A for powering P30? Coz parts for Class A PSU are difficult to source here...
OPT changes?
Miles, thank you for your knowlege, experience and contributions.
What changes would be necessary to use 2SB1560 & 2SD2390 for the OPT's?
Possible to use in the AX14, AX15, AX16, AX17, AX18, AX20 and BX20?
I have 11 extra pairs of these SB/SD devices. Each device will have 0R47 degen emitter resistors.
I have a choice of 2 transformers:
48-0-48 rails @ 350VA
56-0-56 rails @ 300VA.
I await your reply.
Kind regards,
Karl Beistline
Miles, thank you for your knowlege, experience and contributions.
What changes would be necessary to use 2SB1560 & 2SD2390 for the OPT's?
Possible to use in the AX14, AX15, AX16, AX17, AX18, AX20 and BX20?
I have 11 extra pairs of these SB/SD devices. Each device will have 0R47 degen emitter resistors.
I have a choice of 2 transformers:
48-0-48 rails @ 350VA
56-0-56 rails @ 300VA.
I await your reply.
Kind regards,
Karl Beistline
How about the Apex shunt regulator?
100W Ultimate Fidelity Amplifier post #2029.
I have PDF for the layout.
Thanks for the suggestion.
HAve you built it?
Kindly post the layout files/pdf.
Thanks and regards,
Sumesh