Author Topic: Help: Glass for Zenith Y96X or Z96X tuner/preamp  (Read 731 times)

turbineoil

  • Newbie
  • *
  • Posts: 20
    • View Profile
Help: Glass for Zenith Y96X or Z96X tuner/preamp
« on: December 31, 2019, 08:06:02 PM »
I have a 1968 Zenith Y96X (e.g. 960,962,964,966) tuner preamp with broken dial glass. 

Does anyone have a spare PARTS tuner/preamp unit they don't need?  I would like to harvest an intact original dial glass to replace my broken glass.  I believe the dial glass was identical across all of these tuner/preamp models: Y960, Y962, Y964,Y966 Z960,Z962,Z964,Z966.)

Thanks!

chazglenn3

  • Sr. Member
  • ****
  • Posts: 292
    • View Profile
Re: Help: Glass for Zenith Y96X or Z96X tuner/preamp
« Reply #1 on: January 01, 2020, 02:12:36 PM »
Welcome to the asylum! Let me check my stash...
Charles
USAF Veteran

Bill

  • Hero Member
  • *****
  • Posts: 1686
    • View Profile
Re: Help: Glass for Zenith Y96X or Z96X tuner/preamp
« Reply #2 on: January 01, 2020, 04:28:01 PM »
Yes, welcome!  I do not have a stash, at least not for Zenith.  I hope Charles can help you.  Good luck!

Bill

electra225

  • Hero Member
  • *****
  • Posts: 3749
    • View Profile
Re: Help: Glass for Zenith Y96X or Z96X tuner/preamp
« Reply #3 on: January 01, 2020, 07:26:43 PM »
Welcome aboard!  Good luck with your search.
I don't need Google.  My wife says she knows everything.

turbineoil

  • Newbie
  • *
  • Posts: 20
    • View Profile
Re: Help: Glass for Zenith Y96X or Z96X tuner/preamp
« Reply #4 on: January 05, 2020, 02:28:25 PM »
Welcome to the asylum! Let me check my stash...

Hi Charles,

Thank you. I found a generic photo online that shows what my tuner preamp looks like.  The image below is just like mine, but in mine the glass is cracked.  I could have some new glass cut, but it looks like Zenith printed the Zenith logo and crest on the underside of the glass!


TC Chris

  • Hero Member
  • *****
  • Posts: 2475
    • View Profile
Re: Help: Glass for Zenith Y96X or Z96X tuner/preamp
« Reply #5 on: January 05, 2020, 02:58:25 PM »
I've always wondered about making a color photocopy of the dial glass onto clear plastic sheets.  Or take a photograph, clean up damage with a photo editing program, print it onto plastic, and then mount it behind clear glass.  Not as satisfactory as the real thing, but in a pinch it might serve.

Chris Campbell

chazglenn3

  • Sr. Member
  • ****
  • Posts: 292
    • View Profile
Re: Help: Glass for Zenith Y96X or Z96X tuner/preamp
« Reply #6 on: January 05, 2020, 06:03:21 PM »
 Yes, that's the same as my YT960. I know I have a spare tuner, but I'm not sure which box it's in in the garage. Once I find it, I'll have to figure out how to remove it. I'm out of town currently for my granddaughters birthday. I'll try to look for it this week.
Charles
USAF Veteran

turbineoil

  • Newbie
  • *
  • Posts: 20
    • View Profile
Re: Help: Glass for Zenith Y96X or Z96X tuner/preamp
« Reply #7 on: January 05, 2020, 08:39:17 PM »
Hi Charles,

Many thanks! 

Also, do you recommend that I recap the multi-section electrolytic silver can capacitors on the separate amp chassis?  Did you recap your amp?  If so, do you recommend restuffing the silver cans or just disconnecting the cans and installing new miniature caps underneath the chassis?

chazglenn3

  • Sr. Member
  • ****
  • Posts: 292
    • View Profile
Re: Help: Glass for Zenith Y96X or Z96X tuner/preamp
« Reply #8 on: January 06, 2020, 11:04:52 AM »
 I have not as yet serviced the amplifier on this console. I previously owned a 1971 Zenith B966 that used the identical amplifier and one of the members here was gracious enough to service it for me. I don't think he restuffed the can, I think he put the new caps underneath. I have since rehomed that console, so I can't check to be sure.
Charles
USAF Veteran

SeniorSteve

  • Full Member
  • ***
  • Posts: 191
    • View Profile
Re: Help: Glass for Zenith Y96X or Z96X tuner/preamp
« Reply #9 on: January 07, 2020, 01:00:55 PM »
I have a Zenith console a little older than yours, but when I went to replace the filters, I went with a chassis mount ring and not used the FP mount as the original was.  The capacitors had quite a bit more capacity then the originals, but I have dead silence when volume turned down, absolutely no hum.  On the multi section capacitor I did use a terminal strip and connected individual radial lead capacitors to the strip.  On these chassis, remember that the (+) goes to ground, even Charles's B966 model had that.  Even though the capacitors have a plastic insulating sleeve, I did wrap them with black tape where the clamp holds the capacitor to the chassis.
Turbineoil, enjoy your Zenith, they are wonderful sets.  I hope you have the Zenith in house changer with the clamshell 45 adapter.

turbineoil

  • Newbie
  • *
  • Posts: 20
    • View Profile
Re: Help: Glass for Zenith Y96X or Z96X tuner/preamp
« Reply #10 on: January 07, 2020, 02:15:41 PM »
Hi SeniorSteve,

Many thanks.  Would you be happy to post photos of your amp recap?  Do you have a replacement capacitor parts number equivalent list handy?  Do you recommend Nichicon and Sprague for replacements?  Have you tested how many watts RMS these amps put out when up to spec?

The bass, treble and presence pots are all very hard to turn.  On mine, each is connected to a pulley which moves a film strip as well as the pot itself.  Is this a common issue with the Zenith tone controls that move either the film strips or lighted bulbs (on the earlier models like yours) and is there a certain spot that needs to be lubricated so the pots can be easily turned?  If so, where do they gum up (i.e. is it the pot itself or some area of the string pulley film strip mechanism)?  And if the pulley is gummy should turbine oil be used?  And for the pots, what is recommended?  D5?  Faderlube? Etc.  Thanks!

SeniorSteve

  • Full Member
  • ***
  • Posts: 191
    • View Profile
Re: Help: Glass for Zenith Y96X or Z96X tuner/preamp
« Reply #11 on: January 07, 2020, 04:16:29 PM »
Hello turbineoil my bass, treble, and presence controls are a bit stiff because they have to move the dial lamps that show the relative position of the knob, and I think that's why they are that way.  I'll put a picture of the front of my radio panel so you can see the difference.  On the amplifier, I left the speaker coupling caps, the high voltage filters (black can), and the multi-section cap in place.    You can see they were mounted on insulating spacers.  On the capacitors I did replace, you can see I went with saddle mount.  The audio coupling capacitors I just fit underneath the chassis.  Even though I didn't need to replace the fuse, I don't like the style and you can get bit if power is applied to the chassis (don't ask me how I know this).  I went with a panel mount 1/4x1-1/4 size fuse holder and changed it from a 3 amp to a 1.5 amp fuse.  I haven't popped it yet.  I don't know if the same capacitors will work in your console as Zenith upped the voltage on later consoles from 56 volts in mine to 65 volts in the later units.  I don't know where your console will come in.  I can get you a list of parts that I used such as the mounting clamps and such, all I have to do is to find my DigiKey orders for the unit.  Here are a couple of photos of the amp I have (don't have any "before pictures, didn't think I needed them at the time).  If you have any questions, feel free to ask.
Steve

turbineoil

  • Newbie
  • *
  • Posts: 20
    • View Profile
Re: Help: Glass for Zenith Y96X or Z96X tuner/preamp
« Reply #12 on: January 07, 2020, 05:02:07 PM »
Hi Steve,

That's a beauty. Looks like a MM2670 from 64-65.  I bet you could use an EM-87 eye tube to replace the original rare as hen's teeth EM-84 when it gets tired. 

Does your unit have the 12" or 15" woofers?  And is the tuner still tube?  Have you had any challenges with the germanium transistors in the preamp and amp?

How do you like the belt drive changer?  I believe yours is "generation 2" of the 2G tonearm belt drives.  That one has the rubber damping cups in the headshell which I believe GEN 1 and GEN 3 didn't have.  The GEN 3 tonearm is lower mass, but GEN 3 also felt like the arm was a mass market economy move by Zenith engineers.  I bet those GEN 1 and GEN 2 arms (like yours) are better than GEN 3.  Plus GEN 2 has the finger handle!

My tone controls take great effort to turn.  I doubt it's the pot itself.  Something is definitely gummed up somewhere on all three tone controls.  Looks like a chore to dissemble the faceplate to clean and lube those pulleys.   :-X

Nice work on the recap! Is that a selenium rectifier in blue?  My amp doesn't have the blue accordion rectifier; perhaps Zenith moved to silicon rectification by 1967?  If so, do you plan to change that blue one to diodes -- or are those blue rectifiers safe to use in a wood cabinet?

On mine Y series (circa 1967-1968), there are three metal can caps on top of the chassis.  Each metal can cap is sitting on a 4 section phenolic insulator for a 1 3/8" can, like this one: https://www.tubesandmore.com/products/insulator-4-section-fp-cap

A phenolic insulator is cracked and I need to replace it.  It looks like it is held in by two rivets.  Would I need to drill the rivet out from underneath and then get a rivet gut to fasten a new insulator to the chassis?  Any idea what size rivet it would take?

By the way, since all three of the metal cans on my amp are sitting on insulators, are they positive ground?  If so, do the cans have voltage on them if you touch them?  And if so, why are the exterior of the cans not cardboard insulated?


turbineoil

  • Newbie
  • *
  • Posts: 20
    • View Profile
Re: Help: Glass for Zenith Y96X or Z96X tuner/preamp
« Reply #13 on: January 07, 2020, 05:07:26 PM »
Another question: the original bulbs Zenith used were #1847.  I normally don't like LEDs, but having to unscrew the back to replace bulbs turns the wood where the screws affix into pulp.  I'm thinking LEDs would last longer and give off less heat and require the wooden back to be unscrewed less often.  Has anyone experiment with a warm white LED 1847 replacement in their Zenith? If so, how did it look?

turbineoil

  • Newbie
  • *
  • Posts: 20
    • View Profile
Re: Help: Glass for Zenith Y96X or Z96X tuner/preamp
« Reply #14 on: January 07, 2020, 05:08:30 PM »
The powdery dust that grows on the 1847 metal lamp sockets -- is that cadmium?  Yikes!  "Zenith: The toxicity goes in before the name goes on!" ;D