Sony 255 - Heads and alignment?

Odie3

When you let the smoke come out, you broked it!
Hi all.

I have really gone down the rabbit hole working on my Dad's TC-255, which has now been put to the side as 'donor' status. I picked up a TC-255 from Ebay that likely had been in a storage unit for years, in a box wrapped up in a sheet with its Sony cover on it. Calling it clean is a understatement. I pulled all the NOS wheels, run-cap and new belts from my Dad's to this ebay unit (also the serial numbers are light years apart and there are little design differences between the two). Now I have read that Sony's are not looked upon in a favorable light due to their simple single motor/rubber wheel design but this TC-255 deck is a labor of love and I've always known it, since my dad bought it before I was born (which was in '68) :)

While this ebay deck is clean as a whistle and now is mechanically tight as a drum, the heads are worn. Right channel is bright but the left is dull and a bit lower (however sound quality is *much* better than my Dad's).

1. Head coming in from a ebay lot buy. The lot just happens to have a random Sony Head for this deck but it is used and extremely dirty (looks to have sticky tape on it). Was recommended that I lightly/carefully run 1500 Wet Sandpaper on it.,
2. found a place that says they have a +8 head from audioproz.com.
3. Could have one of the heads from the two 255s I have to be 'lapped' @ rfmagnetics.com

All those options are great, just need to figure out which way to go, after I give #1 a try, My real question (sorry it took so long) is once I put any head back on the deck how do I deal with Height & Azimuth alignments?

In my dad's tape stock he has what I *think* I need to use and it seems to be in really good shape. I am not even sure he ever used it. Heck, he might have bought this tape to work in his TC-255 but never got to it. But how does one use it? Do I need a scope?

Thank you for tips and for reading my post.

PS: This is my Dad's before the Ebay unit showed up. This tape was record on the TC-255 it is playing on, from on July 20th 1969. I think everyone will recognize what my dad recorded.



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Well, I have done #1. First on my Dad's head and got 'better' performance (it was really in bad shape). Then I did the heads that came on the unit I got from ebay - great improvement on that one. 10k hz -10db is still a little lower on the left (only slightly moved before sanding) but 400 hz has fully recovered.

There is an adjustment screw at the back of the head that I gather pitches the head from front to back, I did not touch that one when I took the head out/in.

I tighten the screw with the spring on the right, then used the adjustment screw on the left of the head to adjust in 10k hz, trying best to get them both to -10db (or to at least what I think is -10 on the meters). While trying to get -10db, I adjusted Left / Right needs until I thought they were balanced - needles moving in either direction of the screw (in unison). Granted I could have done it completely wrong - what I did was a total guess!
 
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