Yep. That certainly dates you alright.
Hahahaha
They are kind of unique amongst famous musicians, they actually seem like truly decent respectable people.
Some more progress
Got the other channel up and running. Distortion very close to production specs @1 Watt out into 8 Ohms. Running rails off of bench supply at 24V and 1.2 A bias. I adjusted H2 to be about 10db higher than H3 and it is -94 degrees, so progress is being made.
Got the other channel up and running. Distortion very close to production specs @1 Watt out into 8 Ohms. Running rails off of bench supply at 24V and 1.2 A bias. I adjusted H2 to be about 10db higher than H3 and it is -94 degrees, so progress is being made.
Attachments
Tim and Neil Finn were our best export, grew up in a rural town called Te Awamutu in NZ. They put on back yard concerts for family and fiends when they were kids. I saw them in a music festival in the 80s, and loved this song when it came out
1979 SPLIT ENZ LIVE "I SEE RED" WELLINGTON TOWN HALL NEIL TIM FINN - YouTube
nice 😀 A friend had this record in bright red IIRC, we used to hang out listening to records together. Their outfits were so cool. I think Neil records music with his son now.
That is so cool. My son is in a band and writes his own music and records songs.....but all on his computer. I bought him a 48 channel Allen and Heath mix board a few years ago, I already had MCI and Ampex and Otari R-R machines, tons of compressors and EQs, tried to encourage him to learn "the mix board" and analog machines...he didn't want to have any part of it. Oh well, one day I will set it all up when I add onto the house and have my own studio and re-live my radio-studio days of the 80's. All analog processors, tape machines, tube condenser mics etc. Fun Fun Fun.
Cheers
And a little more from "Finn-land" 😀
The Finn Brothers - Won't Give In - YouTube
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Negative 90 degrees does not necessarily mean negative phase harmonic.
In LTspice -90 degrees actually gives you positive phase 2nd harmonic.
If you tell me your Jfet drain and source resistance values, I can confirm what you have.
To measure the effective Jfet drain resistance value measure from the trimpot wiper to the source pin of the mosfet.
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I plan on doing a bunch of measurements today or tomorrow and will post them. At some point, obsessing over analyzing this stuff will get old and I'll just listen.
That reminds me of Tom Scholtz: The Once and Future Analog King: Boston’s Tom Scholz and the Tales of His Sacred Tapes | SoundBard
Sound like too much fun 🙂
I plan on doing a bunch of measurements today or tomorrow and will post them. At some point, obsessing over analyzing this stuff will get old and I'll just listen.
Yeah.
I know this feeling.
I did some measurments on one channel. I also tweaked the DF to 100, which I had not bothered with previously.
Attachments
The Ids values you measured, is that inside the circuit or is this Idss value outside the circuit?
Outside - measured by dividing the voltage across the drain pots divided by the pot resistance - 500 Ohms. The pot on the +24 V rail had 3.3 V across it and the -24 V pot had 3.75 V across it.
I am guessing you measured that without source resistors installed.
Just to be absolutely sure we are on the same page, just confirm what the Idss values you have for 2sj74 and 2sk170 (ie when you tie gate to source)?
This is an important step.
At the moment it looks like you have positive phase harmonic (just a rough calculation in my head).
Just to be absolutely sure we are on the same page, just confirm what the Idss values you have for 2sj74 and 2sk170 (ie when you tie gate to source)?
This is an important step.
At the moment it looks like you have positive phase harmonic (just a rough calculation in my head).
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Active Mosfet Bridge Rectifier.
Active Mosfet Bridge Rectifier - YouTube
You can see radiated noise spikes. It doesn't look like it's affecting the PSU output though (as shown on the ripple).
This kind of stuff plays with my mental well being.
Hahahaha
The passive bridge doesn't suffer this problem as seen in the other video.
I will try and remedy this problem.
Active Mosfet Bridge Rectifier - YouTube
You can see radiated noise spikes. It doesn't look like it's affecting the PSU output though (as shown on the ripple).
This kind of stuff plays with my mental well being.
Hahahaha
The passive bridge doesn't suffer this problem as seen in the other video.
I will try and remedy this problem.
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