Thanks Ed for the early Christmas present. Not pictured are enough caps, resistors, diodes and transistors to populate these boards twice over
The large PCB has most of the passive components, the rest of what you should need are in the bag. The schematic of the amplifier is the same as the one in the box. The rails can be a bit higher voltage as the output transistors are bigger as are the heatsinks. There is also a DC servo on the card but it should be fully populated. Adequate power transformers were provided.
The smallest hold flat pack transformers as marked. The matched set are for a DC powered audio amplifier. It has two amplifiers bridged to provide an output without an output capacitor. It should have a differential input pair followed by a voltage gain stage feeding a driver transistor attached to the output stage. The second amplifier takes it's input from the output of the first amplifier as both stages invert. It was designed with many output transistors to require minimal heat sinking. Each output transistor only used a small individual unit.
I don't have a schematic for these any more. You can use it as a normal amplifier with little modification. Just cut a few traces.
The basic design was first used in the Citation 12.
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Having looked again, it appears the smaller amplifier card is a bridged amplifier, but does not have the differential input stage used by most amplifiers. To make tracing a bit more difficult the card was designed using tape and dots, so TO-92 transistors don't quite stand out. But I assure you, there is knowledge to be learned from tracing out the circuit!
I came to say that I need nothing,
The precious bit of it, that can sing.
The one that does over rail-to-rail swing,
Always arriving even when I stand still.
Now I know it tends to spill charges
But only because of emergencies.
Sometimes small, sometimes larges,
Sometimes swings it's power over seas.
It is just a well thought transistor,
Representing Odin and Tor,
Built from ashes of lost Soul
Planet Earth, we still howl.
The Precious part I seek has name of Nothing
It won't tolerate any useless ranting.
Life is distorted, as we know.
So feels the Source and you are at the gates now.
If you have this magic transistor, twisted or not,
Give it to someone who hasn't seen such cat.
Me, I believe in different reality,
Your offer just doesn't cure my insanity.
The precious bit of it, that can sing.
The one that does over rail-to-rail swing,
Always arriving even when I stand still.
Now I know it tends to spill charges
But only because of emergencies.
Sometimes small, sometimes larges,
Sometimes swings it's power over seas.
It is just a well thought transistor,
Representing Odin and Tor,
Built from ashes of lost Soul
Planet Earth, we still howl.
The Precious part I seek has name of Nothing
It won't tolerate any useless ranting.
Life is distorted, as we know.
So feels the Source and you are at the gates now.
If you have this magic transistor, twisted or not,
Give it to someone who hasn't seen such cat.
Me, I believe in different reality,
Your offer just doesn't cure my insanity.
As to insanity...
Yesterday I ticked off a hospital purchasing agent who wanted to price loudspeakers into each room of a mental ward. He didn't like my non-responsiveness to his description and lost it when I mention my crew and I would fit into a mental ward. He didn't make it to why. Becks on one side of the family and Yochelsons on the other. (I will let others look up those names.)
He also was telling me the rooms in the new ward would have suspended ceilings. For those who have never seen a mental ward room, they often have 20 foot high drywall ceilings with the non opening windows starting 15 feet off the floor. Of course all the furniture is bolted to the floor. Light fixtures are typically flush with the ceiling. (Next step up has the padded walls!) They try to look as cheery as possible if you don't look too closely.
Maybe that has something to do with my giving away free stuff!
Swich yours ships Monday, allow a week for transit.
Anyone else want parts?
Yesterday I ticked off a hospital purchasing agent who wanted to price loudspeakers into each room of a mental ward. He didn't like my non-responsiveness to his description and lost it when I mention my crew and I would fit into a mental ward. He didn't make it to why. Becks on one side of the family and Yochelsons on the other. (I will let others look up those names.)
He also was telling me the rooms in the new ward would have suspended ceilings. For those who have never seen a mental ward room, they often have 20 foot high drywall ceilings with the non opening windows starting 15 feet off the floor. Of course all the furniture is bolted to the floor. Light fixtures are typically flush with the ceiling. (Next step up has the padded walls!) They try to look as cheery as possible if you don't look too closely.
Maybe that has something to do with my giving away free stuff!
Swich yours ships Monday, allow a week for transit.
Anyone else want parts?
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The diyAudio version got started in 2008, and seems to have died in 2016.
Pass Along the Migratory Box of Electonic Junk
Pass Along the Migratory Box of Electonic Junk
I fiddled around with it when I first brought it home. There was a leak somewhere (tested with water), so I started taking it apart .....that was some time ago and I never got back to it.
Too many projects and the list grows longer as I grow older and slower. I haven't made enough PC boards in the last three years to warrant much effort on the that project.
Earlier this year I used the last piece of FR4 stock that I had. I got a "lifetime supply" (about 60 pounds) out of a dumpster on the site of a PC board house in Florida that had been shut down by the EPA back in the early 80's.