PL7000S2

[George S.]

Cleaning the grounds on the LMV-185A meter.
Both PL259 jacks were slightly loose and packed with crap causing a intermittent ground connection.

I may have a line on some NOS Sendust heads as used on the later Japan version of this deck, the CT-A1.
Will they work without internal modifications?
Don't know. Unable to source a late production CT-A1 with Sendust schematic for comparison.
Perhaps the great number of trimmers in this deck will allow that alignment.
Projects on hold until I source heads.
I'll try Sendust before trying the black ferrite Alps.

 

[20tajk7]

The CT-A7 and CT-A9 have sendust heads, might be the same used in the late CT-A1.

 

[George S.]

And, they have available schematics, cool.

 

[MarkWComer]

The heads are junk.

Life is 98% maintenance, and the availability of replacement parts…

 

[George S.]

Well, today my son received a package at the house from NHE Components, Beirut Lebanon, that should have two NOS Pioneer Sendust sandwich heads in it.
I'm on a slow, leisurely, cross country road trip. I'll see what they sent me once I get back home.
Hopefully it's not a pager!
Also ordered one of the Chinese M300 gauge clones, the one with the brass screws.
I do have a very good Mitutoyo digital micrometer to check it's thickness for setting head height.

 

[Gepetto]

Well, today my son received a package at the house from NHE Components, Beirut Lebanon, that should have two NOS Pioneer Sendust sandwich heads in it.
I'm on a slow, leisurely, cross country road trip. I'll see what they sent me once I get back home.
Hopefully it's not a pager!
Also ordered one of the Chinese M300 gauge clones, the one with the brass screws.
I do have a very good Mitutoyo digital micrometer to check it's thickness for setting head height.

Yeah double check those heads George. You never know when they might go off...

 

[WOPL Sniffer]

Trump said he's going to make the Haitians in Ohio use pagers and if they get caught eating cat's and goldfish..................... you know,

 

[20tajk7]

Trump said he's going to make the Haitians in Ohio use pagers and if they get caught eating cat's and goldfish..................... you know,


View attachment 83433

HUH ?

 

[mr_rye89]

I don't think George has any cats or is even in Ohio presently.

 

[WOPL Sniffer]

I don't think George has any cats or is even in Ohio presently.

It's against posting rules to put a "HUH" in a Trump post..... It's automatically assumed................

 

[George S.]

Spent the last couple weeks searching for the Pioneer CT-A1 Service Manual, no luck.
Emailed Pioneer in Japan and got this response.

 

[J!m]

That's one of the nicest "F-OFF's" I've read in a while!

 

[George S.]

I did find one source for domestic Japanese manuals. He did reply the following day that the CT-A1 owners manual is available, but not the service manual.
https://manualshosaikan.blogspot.com/2017/10/ct-a1.html

 

[George S.]

Here's a interesting video of the late CT-A1/Sendust head service with some interesting info on the unit.
Google translate works well for the print.
He also has a video on the early CT--A1/Ferric head, and a link to his site.
Wish I understood Japanese.
There's a link to his site, and his repair business.
Once I get home and can get on a Windows computer rather than the phone, I'll attempt to join his group and hopefully score the schematics.
I did find another site in Europe where they rebuilt a late model with Sendust heads using the PL7000S2 manual.
There were added capacitors across some resistors that weren't shown on the PL schematic.

 

[laatsch55]

Have you checked with Ed , George?

 

[George S.]

No Lee, haven't done so.
I'm thinking they're probably on microfiche and had very limited distribution to Pioneer Service Centers only in Japan.

 

[laatsch55]

I have the CT3 through CT,30...
Not the CT1.
Ed has worked on a bunch of them, I'll give him a call today.

 

[George S.]

Thanks Lee!

 

[George S.]

Got the NOS Pioneer Sendust heads measured with the DE-5000. Very similar results to each other, that's good.
They are similar but slightly different from the Canon Sendust head measurements Alex made available on his website document (Thanks).
I did measure series inductance rather than parallel inductance because the coil resistance was low.

 

[George S.]

The original Ferric head is RPB 060 B.
Going to try Sendust RPB-066-0.
Looks like a good fit without issues.