Friday, March 22, 2024

Japanese Idler-Driven Turntable Part 6: Realistic Mark 8


Just like cars, a new turntable model has to be introduced every year or two to keep consumers' interest and convince them that newer is better.😊

from page 37 of the 1960 Radio Shack Catalog

The Realistic Mark 8 improved upon the similar looking "motor unit-stye" Mark 7 in Part 4 of this series by adding a 16 rpm speed and supplying a half pound heavier cast aluminum platter.

Realistic Mark 8 motor 

Externally, the motor fitted to the Mark 8 looks different. However, the internal construction is very similar to the NEAT P58H motor. Please click here for an illustrated tear down, cleaning and lubrication procedure.

I finally got my hands on a quart of Mobil DTE 25 oil, which is a bit slicker than the Blue 3-IN-ONE oil. So far, all my idler driven turntable motors lubricated with this stuff come up to speed quicker, including the TD124 and Garrard 301. Highly recommended!


After the motor was cleaned and lubed with Mobil DTE 25, the digital tachometer is reading a whisper quiet 1800 rpm. 


Spot on 33.3 rpm under load! 

This RPM measuring device is worth having if you're a DIY-inclined idler turntable user.

Garrard 301 grease bearing vs. the Mark 8 oil bearing

The Mark 8 bearing is identical to its older Mark 7 brother.



Hence, the "nylon countersunk washer thrust pad mod" is also applicable.

NOTE: stepped pulley diameters
From top to bottom = 16, 33, 45 and 78 rpm

I replaced the rubber grommet motor mounts with springs (Grainger Part No. 1NDB4) for better isolation from motor vibration.


There have been unsubstantiated claims that these Radio Shack turntables were manufactured in Boston, MA. I hope the picture above puts the issue to rest.

 Even if the pilot light lens is removable, the neon bulb can't be replaced from the top. Unsolder the connections to the housing and unscrew it from the bottom of the chassis.


If your unit was pulled out of a console or wall installation by an unscrupulous flipper, here's the motor wiring diagram.

Bozz Scaggs 12" single on the Mark 8

Mark VIIIa


from page 62 of the 1961 Radio Shack Catalog


Although it rarely happens nowadays, I got lucky at a flea market with this Mark VIIIa (as per the ad above) with the matching tonearm and Shure M7D with a well preserved stylus. The only thing missing was its idler wheel.😞

Terry Witt idler wheel

I was resigned to keeping it for spares but fortunately, Terry Witt agreed to fabricate a new idler wheel.

Restored Realistic MKVIIIa + M7D spinning Frank Sinatra


A Fraternal Twin

CalRad TT1500

An audio buddy alerted me to this CalRad TT1500 turntable advertised at the popular auction site. The cast aluminum chassis looks different cosmetically, but it's essentially the same turntable; identical cast aluminum platter, motor, main bearing and mechanical layout. 

Realistic Mark 8

All the turntables in this series came from the era when Japan was rising from the ashes of WWII and much needed hard currency was generated by providing high quality OEM products. In less than a decade, they would start dominating the world market for high fidelity equipment.

A Robert Palmer track

Enjoy your LPs!








2 comments:

  1. I really like the shape and colour of the motor unit. Very cool, IMO. I'm starting to think I shouldn't have passed on one of the Japanese idlers a while back.

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    1. I hope you get another opportunity to acquire a Japanese idler driven turntable. They're not quite Garrard 301/401 or Thorens TD124 level but are worthy alternatives to a stock Lenco or Rek O Kut. Good luck!

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