Author Topic: Motorola Stereophonic SK107 - Phono with Vibrasonic  (Read 1067 times)

Motorola Minion

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Re: Motorola Stereophonic SK107 - Phono with Vibrasonic
« Reply #15 on: September 07, 2018, 01:30:35 PM »
I have been playing* this junior stereophonic as I work on the original record changer for this one, which has a different ceramic cartridge. I am hard-pressed to tell the difference between the Astatic 133 and the Sonotone 9t cartridges, each with new stylus. The Astatic seemed to be used on the lower-priced models though the changer only looks different, being the same V-M 1200 series.

Using some records in various states of condition as well as a test record, ambience is characteristic of a Motorola; open and bright, for lack of better terms. One thing the junior requires, that a bigger Motorola does not seem to, is re-adjustment of bass and treble for each record. The bass on the larger models can be overpowering, not so on junior.

This 20-watt model's optimal loudness setting varies between 5 and 8 as well depending on program material. The 51-watt models (3 pair of 6V6) are almost hard to be right in front of at only 3-4!!! It would be interesting to run a distortion test on both, though completely re-capped, may tell something. ???

Another difference with the 51-watt amp is the vibrasonic, on which a setting of 2/10 is plenty, as appropriate for the record. The setting for similar "staging" on the 20 watt model is much higher.     

*The changer I am using is "borrowed" from my SK112 which has the Sonotone cart, like my other "bigger" Motorola a year newer.
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Dave

Motorola Minion

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Re: Motorola Stereophonic SK107 - Phono with Vibrasonic
« Reply #16 on: September 14, 2018, 10:59:00 AM »
As I finish up working on the record changer I am reminded how the idler pulley on these is so prone to drying to a "slippery hardness".

It is so obvious, after all the lubrication is performed, when the cycle mechanism is activated and everything stops. I have one or two good ones out of four to try. The rebuilt one came from V-M and always deliver. Putting it in is like giving the motor a "tune-up" and it powers through the cycles with authority 8)

Here is the Astatic 133 cartridge that is still working fine after 56 years. good thing the needles are still available through V-M, yet list a sub for the cartridge as it is NLA.
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Dave

Motorola Minion

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Re: Motorola Stereophonic SK107 - Phono with Vibrasonic
« Reply #17 on: September 18, 2018, 02:51:46 PM »
I tempted fate by putting the back cover on this console, taking it off my rolling bench, and getting it ready to sell. I mean, why not do that after having a cycle go successfully?

Now it will drop the record, arm moves over, stylus sets down, then picks right up again as if the reject was activated. Either way I have to take it back out again. >:(

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Dave

electra225

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Re: Motorola Stereophonic SK107 - Phono with Vibrasonic
« Reply #18 on: September 18, 2018, 03:54:06 PM »
Record changers can have a mind of their own sometimes.  Putting the back on the cabinet sealed your fate!   ;)
I'm great at multi-tasking.  I can listen, ignore, and forget all at the same time.

TC Chris

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Re: Motorola Stereophonic SK107 - Phono with Vibrasonic
« Reply #19 on: September 18, 2018, 09:24:15 PM »
The phenomenon has a name--one of my favorite phrases--"the perversity of inanimate objects."  Sometimes they take a notion to perplex us.

Chris Campbell

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Re: Motorola Stereophonic SK107 - Phono with Vibrasonic
« Reply #20 on: September 19, 2018, 02:20:03 PM »
Yes, they sure do! I have more issues with V-M players acting up and its probably something I did not put back right.

Then I put a record on yesterday and it dropped/played the FIRST time but did not pick the arm up after the record played ::) Then the second time it did the same thing it had been. Even switching the player on, without turning to reject position, it still does this so there is no manual play. 

Ill work on two newer (1967 and 1969) Micromatics later this evening and I bet they behave just fine. I'm also ready to work on some RCA's. I need a break .

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Dave