Dipole frustration

[N2ADV]

Are you still having issues?

If so, I have an MFJ – 207 antenna analyzer I can let you borrow. That can show you where the dip is in SWR to tell you where the dipole is resonant (without getting out of band for your license class).  I will need it back though. 

Drop me an email (my call at Gmail).

[WG8Z]

Are you using a dummy load to dip and load the 520? if not you could be chasing the dipole SWR around indefinatly.
8' is a TAD low also

[WD8KNI]

Something is making this way too hard.  look at this
http://www.cdagro.com/dip/dpo.html

If you put your antenna into an inverted V configuration multiply each side by .95 as it will be 5% shorter. 

make sure you you don't have anything shorting the inner conductor and shield, make sure that the centers and ends of the dipole are insulated and go for it.

Your TS520S according to the specification will tune 50-75 ohms, in reality it will tune from about 30-350 ohms impedance with no problem.  Been there and had one, a good radio.

Cut your dipole according to the dimensions provided by the calculator, put the SWR meter on the shelf, and start using the radio.   WAY WAY too much emphases is being placed on a low SWR.   I would have stopped at 3:1 that you had, unless you have a very long feed line, that is not a problem for the 520S.   You are not using a modern radio where SWR is a problem.

Here is how I see it, you are young, and have a lot to learn on antenna theory. Get your dipole up as high and in the clear as you can.  Read the 520S manual on how to load it, and start having some fun. 

Modify things as you start to learn.. The 520S has a SWR meter built in if you care.
35 years ago most hams did not have an SWR meter and made thousands of contacts.  Today people think that if the SWR is not 1:1 you can't make any contacts, that though process is rubbish...

Have.. fun.. Fred

[KA5KMS]

Not sure how high your SWR is.  Get an antenna tuner with a built-in balun and SWR meter and build a doublet fed by either 450 ohm ladderline, 300 ohm TV twinlead (if you're not using more than couple hundred watts output), or homebrew some 600 ohm twinlead feedline.  Your finals and rig won't withstand SWR for too long no matter what anyone tells you.  This route is much cheaper than repairing or replacing the radio.  A tuner suitable for use with a TS-520 should be available for less than $75.  So throw the calculators, diagrams and antenna manuals away and start having some fun.  This is the first and last antenna you will ever need.  

[WA8FOZ]

I had not seen this before:

http://www.hamuniverse.com/n4jaantennabook.pdf

 What a wonderful book = so much information, so concise, so clearly written. Commit this to memory and you will know more about antennas than almost any of us  fifty-year hams. Welcome to the wonderful world of antennas. I hope that your career in ham radio will be as rewarding as mine has been!