I can't go through drawing all that ....... 30-th time .........
believe it or not , and search
having electrical short circuit through toroidal xformer isn't a wise thing .
magnetic properties of screw material doesn't have anything with exact problem
just iimagine piece of wire , made of base plate +left screw+Al plate +right screw+base plate again ;
isn't that short circuit , going through (any & both ) toroid ?
believe it or not , and search
having electrical short circuit through toroidal xformer isn't a wise thing .
magnetic properties of screw material doesn't have anything with exact problem
just iimagine piece of wire , made of base plate +left screw+Al plate +right screw+base plate again ;
isn't that short circuit , going through (any & both ) toroid ?
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boys
be serious when serious things are in question
you can stack 2 or zillion of them , that don''t have anything with electrically short circuit , which is main issue here ..
just imagine properly mounted toroid in case : screw from bottom plate , going through toroid center , then small top plate (rubber plates I'm not counting this time ) .
then use your green-yellow wire , connected to one point of chassis already , and connect it to top of toroid's screw
what's happening ?
be serious when serious things are in question
you can stack 2 or zillion of them , that don''t have anything with electrically short circuit , which is main issue here ..
just imagine properly mounted toroid in case : screw from bottom plate , going through toroid center , then small top plate (rubber plates I'm not counting this time ) .
then use your green-yellow wire , connected to one point of chassis already , and connect it to top of toroid's screw
what's happening ?
A person sees themself by projecting their personality onto others, and then watches the reflection come back.
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Gentlemen,
Thanks for pointing out a Shorted Turn.
Is this the problem ?
Shorted Turn - is a closed loop around a magnetic field, which can get a massive current induced into it
Can a magnetic field induce a current in aluminum and stainless steel ?
However, could the magnetic field induce a current in the ferrous washers - which would then be conducted by the aluminum loop ?
To be on the safe side - I should break the loop.
Mounting diode bridges on top of the donuts is a technique I've seen on a few amps (with a single donut).
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Thanks for pointing out a Shorted Turn.
Is this the problem ?
Shorted Turn - is a closed loop around a magnetic field, which can get a massive current induced into it
Can a magnetic field induce a current in aluminum and stainless steel ?
However, could the magnetic field induce a current in the ferrous washers - which would then be conducted by the aluminum loop ?
To be on the safe side - I should break the loop.
Mounting diode bridges on top of the donuts is a technique I've seen on a few amps (with a single donut).
.
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David,
Again - I stole the idea of gluing the electrolitcs down with hot glue
and wiring them P to P from a Blue Circle BC 1022 power amp.
The BC1022 An Exceptional Solid State Stereo Power Amplifier New Sounds Audio
The case and electrolytics were cleaned with alcohol (not beer) and the bond is so strong now,
I don't want to risk trying to pull them off.
In hind site - think I would have used water based contact cement.
P to P wiring of the electrolytics is a good technique.
However, its important there is good metal to metal contact before the solder is applied.
Bridging conductors with solder is not good.
However - I suspect soldering probably needs to be fast before too much heat damages the caps.
BTW: I used Cardas Quad solder - which has lead in it - yuk - but it flows quickly.
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Juma was right.
When the 0R1 source resistors were removed - and replaced with 0R47, the F5 became thermally stable.
Its very well behaved now.
Unfortunately - biased at only 0.5 Amps - and there is about 40 mVpp ripple on each supply rail.
Very disappointing - I thought only women could break my heart.
This is a new power supply - will it improve if the electrolytics break in ?
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When the 0R1 source resistors were removed - and replaced with 0R47, the F5 became thermally stable.
Its very well behaved now.
Unfortunately - biased at only 0.5 Amps - and there is about 40 mVpp ripple on each supply rail.
Very disappointing - I thought only women could break my heart.
This is a new power supply - will it improve if the electrolytics break in ?
.
Attachments
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Yes. the resistance between the case and the plate was 0.
As a short term solution - I removed one of the bolts.
Long term solution - probably make a single plate for each donut.
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In your case less a tragedy, the magnetic vector of both cores are not in phase (for same side up).
Turn other toroid around, and you is in Doo-Doo.
(me always talk in first-person narrative, similar to "We, the King", but in my case "I, the Idiot")
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Here is my test set up
H/K 7600 CD player ==> Musical Fidelity v3 tube buffer ==> F5 Amp ===> scope & 10" Tannoy
changing one variable at a time
1) paralleling up the input jFET's increased the bass, dynamics and the music moved more forward.
Unquestionably, this mod is a keeper with the Gamut style MOSFET's.
2) The source resistors are presently 0R51 - I don't have 0R22's.
But from previous tinkering, I know there will be more bass if this value is lowered.
3) The 4 F.B. resistors were always 50 = R5 // R6 and 50 = R7 // R8
4) I moved the bias up to 1.3 Amps - I think it sounded more alive ???
Notes
When the bias was increased to 1.3 Amps - the ripple on the supply rails increased to 90 mVpp - not good
The amp is very thermally stable - when I switch it on, the voltage drop across the 0R51 source resistor is about 0.64 v
1/2 an hour later its 0.70 v
Switching on and off the F5 is very well behaved - no thump - no output hitting the voltage rails.
No output relay required.
92,000uF per channel should throw a 10" Tannoy around like there is no tomorrow.
But there is no bass.
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