Technics RS1500 head rewiring

[High and Outside]

Hello Ketchup,

Welcome to the forum. Before answering, I'd like to call your attention to our groundrules. We ask that all participants in the forum use their real names. Please either add your real name to your profile or sign your posts.

Now, regarding your heads: These machines were made in two versions: one with half-track record and play plus an additional quarter-track repro, the other with quarter-track record and play plus an additional half-track repro.

Your visual description of your heads seems accurate. If the half-track head comes first and your quarter track head comes last, that indicates that you have a quarter-track recorder-reproducer with the additional half-track repro head. Does the record head (that's the one that's third in line, the one right after the reversing idler) look like a quarter-track head? And look at the head switch...does the label "2-tr" appear on the left or the right side of the switch? If it's on the left, that further confirms that you have a quarter-track headstack. Let's determine that first, then we can figure out the wiring.

BTW the color code that Doc posted corresponds to what my manual shows for a half-track machine. It doesn't show the wiring of a quarter-track headstack.

[ketchup]

Sorry about the name thing and thanks for all the info so far.  I must admit that I did not read the rules before I posted the question!

Paul, the answer to all of your questions is "yes."
The model is a 1506 which is supposed to have a 1/4 track record and play head plus an additional 1/2 track repro head, so at least it looks like the deck hasn't been messed with in this regard.

I wonder if the two models here (1506 and 1520) just have the repro heads wired oppositely.  Hopefully someone has a manual for a 1506 so we can know.  Actually, I'm not all that concerned with which is R & L because this will be revealed by listening to a familiar tape.  The biggest concern that I have so far is getting the phase correct for each channel.

While we're on the subject of wiring heads, what's a good, shielded wire to run to te Seduction?  Any recommendations as to where I can get some without buying it in a huge quantity?

Thanks again,
Kevin

[ironbut]

The service manual I have for my rs1500us has a supplement for all the differences in the rs1506. The only parts changes are the head base plate, the deletion of a head spacer and the different heads. The colors I gave you on the Bottlehead forum were for the 1500 and because of the 1/2 and 1/4 track playback heads being on the opposite side of the head block, I'm sure the wiring is the other way around like you said. The 1/2 track head should be centered while the 1/4 track is off set. Following the tape path;
#1. 1/2 track playback
#2.1/4 track erase
#3.1/4 track recording
#4.1/4 track playback

[xcortes]

SUCCESS:

I rewired my RS1500 this morning. I'm listening t6 it right now through a Seduction (phono) just to test it. It works perfectly.

By tomorrow I should have my tape modified Seduction up and running to be able to start playing with the alignment tape and maybe, just maybe, I'll be ready to play TP-01!

[stellavox]

For what it's worth, the stock playback head can be pressed out of it's case and replaced by a "B" case pro-Nortronics. 

I tried posting a pic but the file is too large - Email me if you'd like more info

Charles

[timmieec]

hello everyone!

for anyone looking for the link to the gold mine of an article Doc posted in reply #3, here it is :)

https://web.archive.org/web/20140208001224/http://www.bottlehead.com/et/adobespc/Seduction/bottleheadtapeheadpreamp.htm

there's also a more recent, very short thread discussing this topic: https://forum.bottlehead.com/index.php?topic=13548.msg123625#msg123625

cheers!
Timothy
New Tapehead