You mean National Ignition Facility? That one is orders and orders of magnitude more energy than the one I was working on at Cornell.
They really haven't done so well - the amount of energy and the delivery frequency has evolved up and up and up and up over the years....
Sorry to be so dense that I would think with these listed issues I should make repairs/replacements.
I sincerely do appreciate everyone's time and interest.
90% of the Electrolytics were outside 20% tolerance
80& of the Transistors were very low HFE, below 50
80% of the Resistors were outside 5% tolerance
Drivers and Outputs are random and not the same, plus low Hfe
Also see post 44 & 46 as an example of the Ceramics Spec is 0.1uf and they measure 0.067uf that appears to be out of spec, my misunderstanding.
Also the Fuse Resistors had been changed out to Carbon Film
In regards to the Symbol Schedules and Parts List, I felt there was a discrepancy but now I see it is just me.
I sincerely do appreciate everyone's time and interest.
90% of the Electrolytics were outside 20% tolerance
80& of the Transistors were very low HFE, below 50
80% of the Resistors were outside 5% tolerance
Drivers and Outputs are random and not the same, plus low Hfe
Also see post 44 & 46 as an example of the Ceramics Spec is 0.1uf and they measure 0.067uf that appears to be out of spec, my misunderstanding.
Also the Fuse Resistors had been changed out to Carbon Film
In regards to the Symbol Schedules and Parts List, I felt there was a discrepancy but now I see it is just me.
I sure would like to see a Fusion Reaction on a Grand Scale before my death. Many technology advancements have came from the LLNL Laser Programs, MFTF, Tokamak, SHIVA, NOVA and LIS to mention a few. Not to mention the current collaboration with CERN.
I bought it knowing it had some issues but not to this extent. No ill feelings about it.
Hate to pee on yr parade, but the idea of NIF being a power-producing program would involve tens of shots per second with a decent yield. They can only manage a shot or two per day at present, just barely able to eke out some fusion neutrons. I want fusion to happen, too, but the hurdles are still rather huge. Getting to a point where someone actually wants to pony up money for a power plant doesn't look to be a possibility right now.
There are universal replacements for input gain transistors, VAS, and output transistors. All, except TO3 transistors, can have their pins in any order... you just need to know what you are doing. So, it shouldn't be difficult to use whatever will work. You are re-doing the whole amplifier... it seems.... so, you should know how to select the equivalent transistor.
Anyway, we are not talking high-end amplification here... just look at the amount of hook-up wiring used, contact resistance galore, fuses on PCB DC tracks...
Resistors... use carbon film or metal film... except when you can tell from the schematics that they should be fuseable (fail-open).
Capacitors.... just like-for-like will do. I'd avoid silvered mica and tantalum for analog application...but even those will work in your amplifier just fine.
I suppose you are probably just taking it all too seriously... are you trying to improve the sound, i.e. modify the amplifier to sound better?
If you are trying to do something special.... choose one of the FW kits. Otherwise, there's simply no point in worrying too much about something that was produced 50 years ago.
Anyway, we are not talking high-end amplification here... just look at the amount of hook-up wiring used, contact resistance galore, fuses on PCB DC tracks...
Resistors... use carbon film or metal film... except when you can tell from the schematics that they should be fuseable (fail-open).
Capacitors.... just like-for-like will do. I'd avoid silvered mica and tantalum for analog application...but even those will work in your amplifier just fine.
I suppose you are probably just taking it all too seriously... are you trying to improve the sound, i.e. modify the amplifier to sound better?
If you are trying to do something special.... choose one of the FW kits. Otherwise, there's simply no point in worrying too much about something that was produced 50 years ago.
TO-3P transistors were originally intended to drop into a TO-3 outline, though they might need a rectangular insulator rather than the diamond-shaped TO-3 insulators. There are a couple of TO-3P devices available at Digi-key that might be suitable as replacements for the original TO-3 devices used in this appliance.One is from Sanken, and one is from On Semi.Both appear to be as zippy as the original TO-3 devices used here.
Sure... whatever will work. As long as the DC stability is okay, and the amp does not oscillate even with a bit of capacitive load at the output.... Bob's your uncle.
My plan at this moment in time is to use: 😒
MJE15032G & MJE15033G
MJ15003G & MJ15004G
My love for the Yamaha CA Series goes back this 47 years to my time of selling Yamaha Audio Equipment.
Nice absolutely irrelevant name dropping, including CERN and Star Wars, I wonder WTH does it have to do with a supposedly abused pawnshop grade 50 y.o. piece of consumer electronics.
So I repeat my question:
And no, "parts are with the USUAL tolerance spread in a pawnshop grade 50 y.o. piece of consumer electronics" is not enough to put Forum Tech minds to work in a "non problem".
Bring some challenge and it will definitely trigger interest .... but as is .....
Personal suggestion: "improve" nothing, just replace what is burnt/shorted/cracked with working parts, same type and rating.
Don´t reinvent the wheel.
There are a few safety important parts such as fusible resistors which demand exact same type on safety concerns (as in catching fire and burning your house down), follow schematic suggestions to a T
So I repeat my question:
And no, "parts are with the USUAL tolerance spread in a pawnshop grade 50 y.o. piece of consumer electronics" is not enough to put Forum Tech minds to work in a "non problem".
Bring some challenge and it will definitely trigger interest .... but as is .....
Personal suggestion: "improve" nothing, just replace what is burnt/shorted/cracked with working parts, same type and rating.
Don´t reinvent the wheel.
There are a few safety important parts such as fusible resistors which demand exact same type on safety concerns (as in catching fire and burning your house down), follow schematic suggestions to a T