The sub microscope is great for looking at and measuring vita (SRA).
The trick is to put the stylus down (gently) onto a CD that is well lighted. You can then use the software to determine the lead and trailing edges of the stylus and using the right equation can determine SRA. |
Dino-Lite has measuresoftware in the software. |
Thanks Lubachl.
I used Adobe illustrator as it gives a bit more control over the placement of lines, then printed out the image and measured the angle.
The veho is fairly cheap, I believe the dynolite has some software to enable the placement of measurement lines.
I had to remove the clear plastic cowl around the lens on the veho to be able to get the scope close enough to focus. I think this also necessary for the dynolite.
It is very fiddly to position the scope relative to the stylus to get a good image. Time and patience required in abundance. A longer working distance might well be an advantage.
Fremer on his analog planet site describes his methodology for using a usb scope. |
Great pictures Nine and Veho. From the microscopic view, how do you get the overlapping lines for SRA/VTA? Do you photoshop them in and then estimate the angle or does the microscope have a grid on it? Also, in looking at the digital microscopes some of them have a longer working distance which would seem to me to be a better option. Comments? |
Great pictures ninetynine.
I have used a cheapish scope, a Veho 400x from amazon.
http://www.veho-world.com/main/shop_detail.aspx?article=40
Not as good as the Dynolite but does give decent results. Needs a lot of patience to get clear images
this is a photo of my Lyra at approx 91/92 degrees in my 4point arm which has adjustable VTA.
https://www.dropbox.com/s/hygrlyr7nm7ydsi/Atlas-92.5-degSmall.jpg?dl=0
It is a useful way of getting a ball park figure and yes there can be errors. Fremer gives step by step guide on his analog planet site.
After an approx initial set up with the microscope, I adjusted the SRA/VTA by ear. Then checked again with the scope, that is the image link above. I was reassured that the best sounding position correlated with the visual confirmation.
I use a mini oscilloscope and test tone LP to adjust the azimuth. |
Here some pictures with a Dynolite 220x
https://www.dropbox.com/s/49jq2eyqssnr43w/EMT%20JSD6%20Diamamond.jpg?dl=0
https://www.dropbox.com/s/kqe3cqruvtq128z/Diamant%20verdreht%20Skala.jpg?dl=0
https://www.dropbox.com/s/skw82l9yohw3pna/VTA%20Kleos.jpg?dl=0
https://www.dropbox.com/s/f6a9ow4gam58u3v/AT%20OC-9.jpg?dl=0
https://www.dropbox.com/s/wmokgjww3nxvyx5/AT-OC9%20Mikroskop%20Verrundung.jpg?dl=0
https://www.dropbox.com/s/c4mo6g2avtkbnin/Black_von%20seite%20220fach.jpg.jpg?dl=0
What is very important is a possibility to place the microscope good and to move it sensitive.
I have rebuilt a vernier height gauge.
https://www.dropbox.com/s/yvbpuz3hp3yt572/Dino%20Lite.jpg?dl=0 |
Although we are 5 yrs down the line I agree with Stanwal. ;^)
The Graham is the easiest method I've ever used and the most easily re-checked (i.e. by putting it back on the jig any change in position due to applying the stylus guard or loosening of cartridge screws is immediately apparent - as I discovered recently!)
The only advice I would give is to be careful with self-induced parallax errors.
The Graham method is very comfortable and easy on the eyeballs with minimal risk of damaging the cart during install.
On the subject of parallax errors I would also suggest that using a 400X or 800X magnifier on a cart is not as straightforward as the casual purchaser might think. Ideally, the cart would be attached to a machined platten with the microscope locked on to it and with the capability of adjusting it to an exact measuring position. Since you really want the stylus to be standing upright on the LP at the time of measurement such accuracy isn't even remotely possible without a variety of angular errors occurring. Eyeballing cartridge vs microscope orthogonality isn't a reference point I would personally rely on.
Just my opinion... |
Microscopes need lots of expertise resulting in limited reward. You need a MINT protractor (follow the directions carefully...it may take a couple of days...rest often...check and recheck) and if you have a VPI arm or similar, you need a Fozgometer with its accompanying test record.. a scale for weighing,.a flashlight, and a 10x hand held glass. Its not hard to set up a cartridge, just tedious. That's why you should do it yourself...are willing to take the time and energy to do it right. |
Did buy a XCsource USB microscope 800x 8 Led from an AD in Amazon , but up until now I 'm not fully satisfied by the result by examen the stylus .Is this the right USB by specs ? Or should I use one with more magnification .BTW after replace the battery in my FOZ by an external 230V AC to 9 V DC supply it works perfect. |
Magnifying 100 times plus(microscopes) are good for looking at a stylus for wear.The more light you have on it,the easier it is to see,no matter what your vision is.The Fozgometer may give a headache in some cases as seen in this this thread. Link.[http://forum.audiogon.com/cgi-bin/fr.pl?eanlg&1291669919] |
The thing I really like about the Graham arm is that you align the cartridge by mounting it in the arm tube, then putting the tube on its back and placing the alignment gauge over the cartridge. So you are looking DOWN at the stylus THROUGH the alignment gauge.It is like viewing a standard protractor from underneath. Despite my admitted defects of vision I was able to get an alignment that was checked first by my tech friend with a microscope and then by another friend who has a Fozgometer or whatever, that new fancy gadget. Both of them thought it was as close as practical; i.e., any further effort would probably make it worse. So if your eyes have seen better days and you are considering a new arm then this is a virtue of the Graham to remember. I am not connected to them except as a user. |
All you really need is a penlite halogen flashlight and a hand held magnifying glass.
Might cost $10 total.
KISS
IMO |
Can I suggest that you try specwell monocular 10 x20 or 14 x 20 ( 14x magnification ) , close up lens 20mm aperture , tripod mount and a camera stand for less than GBP 200 from optimalowvision dot co dot uk. Setting up catridge using mintlp used to be time consuming and a pain . With specwell short focal length monocular , it's much easy to set up catridge and more accurate and within a much shorter time |
Glai,
Thanks for you resposne. I will check out the Dynalite. Yes, its not only my eyes that I am struggling with but also my neck and back. |
I am using dynalite USB scope for this purpose now. I initially got it to measure SRA. It is very precise and better than 10 times lupe. This is a big plus if your carts have large body obscuring the stylus like the Coralstone. I have multiple arms so there is little space to stick my head betw the arms. My neck and back are very thankful of this device. |
I should have added that I find a magnifying visor to be a great help, if sometimes awkward to use. On other occasions the small battery lights that attach with a headband make repairs a little easier. |
Some web cams will also do the trick. |
I know exactly what you are talking about; 20 years ago I use to align cartridges for fun, now it is a real pain. At the same time the cult of PERFECT ALIGNMENT has ascended to make us all feel guilty if we don't spend hours on it. I am willing to settle for PDC alignment myself; sometimes I get it very close but I don't obsess about it. So those of you with failing eyesight or short attention spans take heart, you are not alone. |
