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PostPosted: March 1st, 2019, 1:20 pm 
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From the specs of most supercaps I have seen, they recommend having a series resistor (or light bulb) to charge them up, so they are not a dead short on the charging system.

I have an older 80F, 20V cap I used for 12VDC battery supply and used a 12V bulb in series with the cap to charge. Once up to charge the bulb goes out and ready to go with visual feedback.

Just a thought.


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PostPosted: March 1st, 2019, 1:25 pm 
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HAL wrote:
From the specs of most supercaps I have seen, they recommend having a series resistor (or light bulb) to charge them up, so they are not a dead short on the charging system.


As I mentioned earlier, the charger will have a 15ohm output impedance (read 15ohm resistors in series with the outputs).

Roscoe


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PostPosted: March 1st, 2019, 1:42 pm 
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:character-oldtimer: Records are so 1890..


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PostPosted: March 1st, 2019, 2:26 pm 
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David McGown wrote:
:character-oldtimer: Records are so 1890..


I developed a couple rolls of black and white film last night. I DIY'd my developer, but it's based on a developer that was patented in 1881. You can still buy it. Believed to be the oldest photography product still in production...

Roscoe


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PostPosted: March 1st, 2019, 5:18 pm 
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David McGown wrote:
:character-oldtimer: Records are so 1890..



You say that, but I'll bet you never heard exceptional LP playback. And no -- the Capital Audiofest did not have any exceptional LP playback.

Every time I play vinyl -- old vinyl and new production alike -- I cannot believe the level of transparency and musicality that is hidden in those grooves.

Dragging a chunk of crystallized carbon through the grooves that is attached to a lever that drives a magnetic circuit never ceases to amaze me.

The recording process, mastering, editing the cutting tape to drive the cutting amplifiers, the cutter, plating the acetate, making stampers, melting plastic to form the record, the whole process (of which I've had personal involvement) would -- taken at face value would seem crude and backward -- yet the entire process is critical (we're talking micron level) and has been developed over decades to provide the very best fidelity that is humanly possible.

Modern playback equipment has demonstrated to me that during the peak of vinyl production in the 50's and 60' no one back then had playback equipment that was capable of exploiting the media to the level possible now. That's why there is resurgence of vinyl playback. And then there is direct-to-disc recording bypassing recording to tape first that really shows off the capability of vinyl.

:character-oldtimer:

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PostPosted: March 1st, 2019, 5:39 pm 
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Seriously Wally? David McGown has one of the finest LP playback systems in our group. He has home built tables that are beautiful looking as well as sounding. He has a great set of ears as and knows good sound.

Plus he is great friends with Charlie, who probably has the best LP system around.

David has heard great vinyl. He owns it.

His remark was a joke.

Have a little respect sir.


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PostPosted: March 1st, 2019, 6:21 pm 
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Speaking about photographic chemistry, if anyone is interested in using standard B&W negative film and winding up with positives, I have the formula for the Arnelon method of processing that negative film as positives. We used it when I was teaching FDA agents photography at UC Berkeley back when I was a student, you know when the dinosaurs were still around. It gives a very long tonal range.


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PostPosted: March 1st, 2019, 8:35 pm 
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SoundMods wrote:
David McGown wrote:
:character-oldtimer: Records are so 1890..



You say that, but I'll bet you never heard exceptional LP playback. And no -- the Capital Audiofest did not have any exceptional LP playback.

Every time I play vinyl -- old vinyl and new production alike -- I cannot believe the level of transparency and musicality that is hidden in those grooves.

Dragging a chunk of crystallized carbon through the grooves that is attached to a lever that drives a magnetic circuit never ceases to amaze me.

The recording process, mastering, editing the cutting tape to drive the cutting amplifiers, the cutter, plating the acetate, making stampers, melting plastic to form the record, the whole process (of which I've had personal involvement) would -- taken at face value would seem crude and backward -- yet the entire process is critical (we're talking micron level) and has been developed over decades to provide the very best fidelity that is humanly possible.

Modern playback equipment has demonstrated to me that during the peak of vinyl production in the 50's and 60' no one back then had playback equipment that was capable of exploiting the media to the level possible now. That's why there is resurgence of vinyl playback. And then there is direct-to-disc recording bypassing recording to tape first that really shows off the capability of vinyl.

:character-oldtimer:


Wally,

It was a joke. I was just making an overly subtle point that we are all using "old" technology in our pursuit of great sound. Now how about using Leyden Jars in the power supply for a real "retro" look. Want to go fly a kite to recharge :lol:


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PostPosted: March 2nd, 2019, 8:48 am 
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Location: Parkville, Maryland
Wally,

It was a joke. I was just making an overly subtle point that we are all using "old" technology in our pursuit of great sound. Now how about using Leyden Jars in the power supply for a real "retro" look. Want to go fly a kite to recharge :lol:[/quote]

That'll work. Speaking of retro. The Capital Audiofest two years ago had a vendor set-up a turntable with two arms. One with a stereo cartridge and the other with a mono cartridge. Both cartridges were from the same manufacturer and with "Hi-End chops. Out comes this mono Jazz recording first played with the stereo cartridge -- NICE! Then the same recording played with a mono cartridge -- WOW!!! The difference was dramatic! Better clarity, improved musicality, the presentation as a whole was superior.

I hadn't had a Hi-Fi Gee-Wheez moment like that in years.

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PostPosted: March 2nd, 2019, 1:19 pm 
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Joined: January 15th, 2015, 7:19 am
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Location: Baltimore MD
but he still played through Stereo Speakers.
Should have moved speakers together or use one speaker


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