Chill out, Neil! We're having fun! You're right, of course. Sorry to car-jack your thread. I've bookmarked it for reference when my next table shows up. It's been almost 6 months. I think I getting hives!
How to set SRA after determining true vertical?
Here is a picture of a stylus with zero rake angle:
http://members.cox.net/nsgarch/SRA@%200.0%20deg.jpg
Since all modern styli are symmetrical in the x and y plane about the verical z axis, the tapered stylus and its reflection will make a perfect "X" when vertical (z axis perpendicular to the groove) and viewed from the side.
This condition is established by raising or lowering the tonearm pivot post. Once you find this point, and assuming you have a typical 9" tonearm (about 230 mm from pivot to stylus) then each 4 mm you raise the post from the zero
SRA point will apply one degrewe of SRA to the stylus.
A test setup is shown in these two pics:
http://members.cox.net/nsgarch/SRA%20setup1.jpg
http://members.cox.net/nsgarch/SRA%20setup2.jpg
Equipment includes:
a mini Mag-Lite flashlite,
a first surface mirror from old SLR cameras -- easy to find at photo repair shop)
a 50X pocket microscope
bean bags
Don't forget to first remove antiskate and set VTF.
.
http://members.cox.net/nsgarch/SRA@%200.0%20deg.jpg
Since all modern styli are symmetrical in the x and y plane about the verical z axis, the tapered stylus and its reflection will make a perfect "X" when vertical (z axis perpendicular to the groove) and viewed from the side.
This condition is established by raising or lowering the tonearm pivot post. Once you find this point, and assuming you have a typical 9" tonearm (about 230 mm from pivot to stylus) then each 4 mm you raise the post from the zero
SRA point will apply one degrewe of SRA to the stylus.
A test setup is shown in these two pics:
http://members.cox.net/nsgarch/SRA%20setup1.jpg
http://members.cox.net/nsgarch/SRA%20setup2.jpg
Equipment includes:
a mini Mag-Lite flashlite,
a first surface mirror from old SLR cameras -- easy to find at photo repair shop)
a 50X pocket microscope
bean bags
Don't forget to first remove antiskate and set VTF.
.
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- 86 posts total
Dan,you can E-mail me at Sir Speedy [email protected](just leave out the "0" in my usual 70680). Best! |
T thought I'd better come back and make ammends to this thread by posting something useful. :) If anyone is looking for a source for front surface (aka first surface) mirror I can recommend a couple of internet sources. www.fsmirrors.com This site is perhaps the better choice of these two with better prices and selection. There is a 4"x5", 3mm (1/8") pre-made for about $21 shipped. www.anchoroptics.com This site has a commercial grade pre-made mirror that is about 2"x5" and 3mm thick for maybe a dollar or two more. |
- 86 posts total