Whoa, that was years ago, good memory..
. I've since tiled a master bath floor, full shower, the downstairs bath floor, and subway tile on the wall..both baths have radiant heat under, man that feels good on da feet in da winter..but boy, a 350 lb tub? Sheesh.. I will say though...minivans rule!!I cannot answer that, I've never measured. My snake construct was created to solve a huge noise issue...I had a big problem, figured what the solution was, built it, and it totally eliminated all noise (below audible, but unkown how far below).. I didn't have to get my hands dirty with that disgusting "test equipment". Once the snake worked, the system was not broken...so I felt no need to "fix" it..
ps.. along the line..For the most part, my concerns have been near field coupling as opposed to farfield. The techniques for rf rejection can be significantly different than that of rejection of shield currents or loop trapping. RF, ya gotta ask others for that.
jn
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TY.
(Haven't you heard, the web is frequented by psychopaths, who monitor your every move. One specimen is relocating to the 90F caribbean permanently in a couple of years, with a Sjögren's g/f that can't handle aircon, in pre-design experimental stage of a floor&wall cooling system with mixed natural ventilation)
Mr Simon,
thanks for the link. (reminds me of the time I left an LP out in the open in the morning, before the sun made it to the corner)
As a groovy metaphor observer, a glimpse of a parallel universe : http://ethesis.unifr.ch/theses/downloads.php?file=StotzerS.pdf
(Haven't you heard, the web is frequented by psychopaths, who monitor your every move. One specimen is relocating to the 90F caribbean permanently in a couple of years, with a Sjögren's g/f that can't handle aircon, in pre-design experimental stage of a floor&wall cooling system with mixed natural ventilation)
Mr Simon,
thanks for the link. (reminds me of the time I left an LP out in the open in the morning, before the sun made it to the corner)
As a groovy metaphor observer, a glimpse of a parallel universe : http://ethesis.unifr.ch/theses/downloads.php?file=StotzerS.pdf
What distortion did you get at 2Hz with a 1uV input? Or were your measurements taken at voltages that are physically impossible?
Kind of hard to measure 1uV output at 2Hz. Can you do it?
However, I thought about the 'extrapolation' that was done, and it looks pretty good, BUT is it really worst case? What about 1Hz with a 10 ohm source? For the record, most MC are not at 100uV, that is just a low estimate for S/N. Typical cartridges are more like 300uV@ 3.54 cm/sec or 5cm/sec peak. Now, let's estimate what this 'typical' MC transformer does with 10 ohms, 1Hz, and 300uV. Hint: It will be significantly worse than previous estimates, based on the Jensen mc transformer graph.
However, I thought about the 'extrapolation' that was done, and it looks pretty good, BUT is it really worst case? What about 1Hz with a 10 ohm source? For the record, most MC are not at 100uV, that is just a low estimate for S/N. Typical cartridges are more like 300uV@ 3.54 cm/sec or 5cm/sec peak. Now, let's estimate what this 'typical' MC transformer does with 10 ohms, 1Hz, and 300uV. Hint: It will be significantly worse than previous estimates, based on the Jensen mc transformer graph.
You told me to look at a scope, so presumably that's your recommendation. I thought that was ludicrous, but hey, you're the engineer.
In any case, if you plug in your new numbers, you're up to 4uV at the point where the cartridge is in severe distortion. Want to try to move the target again?
In any case, if you plug in your new numbers, you're up to 4uV at the point where the cartridge is in severe distortion. Want to try to move the target again?
Nice survey of cartridge types, jeez they tried EVERYTHING, even a variable reluctance RF (I had a swept RF generator that used that). I'd love to see one of those gold ribbon carts. I also love some of the "colorful" ways he describes how bad things get on LP's.
The stylus geometry does play into the mis-alignment problem.
Here's one from 1956 (smiling g/f not included) they used Peltiers. Mass quantities of solar panels (~.3% net efficiency) and you're home free.
http://www.vacuumtubeera.net/RadioAge-1956-10.pdf
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Interesting article.
Not much on anti-skate though. I used to use a 12 inch record with no grooves cut into it to adjust antiskate in the club, but I always wondered if the modulation of friction due to the grooves was much different than simple vertical friction.. And it didn't take very long to realize that antiskate was entirely useless when I was scratching. There, I'd have to run out to about 5 grams tracking to keep the needle in, and drop antiskate to zero.
jn
John already said that he DIDN'T do the measurements since he didn't know how to generate a 1uV signal. If you're going to misquote, misquote accurately. Since the order of magnitude is ridiculously low, you can do a "complete calculation." Don't forget to take into account the -150dB resistor distortion from loading.
Scott said nothing that's inconsistent with what I've measured or claimed. Where do you get this stuff?
Scott said nothing that's inconsistent with what I've measured or claimed. Where do you get this stuff?
Yes geometry does count.
What I found interesting was the coverage of the moving coil cartridges. 11 mV at 1 cm/S output for one of them. The "RCA Test Record" had a maximum velocity of 18cm/S/ Almost 200 mV from a moving coil cartridge!
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