Columbia Vivatonal 711 question

[dzavracky]

Can someone explain what this extra barrel is for?

David

[JerryVan]

It's a 3 spring motor. That's the third spring.
Like a "third wheel" on a date, it's not wanted by the couple.

Is this something you bought?

[dzavracky]

It’s a customers machine; I went and picked it up for him yesterday.

Why is the spring barrel so small?

David

[JerryVan]

It’s a customers machine; I went and picked it up for him yesterday.

Why is the spring barrel so small?

David

Because it only holds one spring, versus the other barrel, which holds 2. The narrow one should be roughly ½ the length of the wide one, which it appears to be.

[dzavracky]

Thanks Jerry!

The motor doesn't run at the moment... but I am really looking forward to taking this motor apart.

Cheers,

David

[BillH_NJ]

I would like to see it running. The only Viva-Tonal I have (aside from a portable) is the smaller 720 and I use it less than my Credenzas and Sonora Philharmonic.

[larryh]

I have the 800 Viva Tonal and I had the motor worked on, its a three spring as well. For some reason as you mentioned the springs are rather small for a large machine and on mine you won't get more than one play of a 12" record. Maybe two 10", but I doubt it. Beware that the motors are quite difficult to adjust and the fellow who did mine said he wouldn't do another!

Larry

[dzavracky]

I have the 800 Viva Tonal and I had the motor worked on, its a three spring as well. For some reason as you mentioned the springs are rather small for a large machine and on mine you won't get more than one play of a 12" record. Maybe two 10", but I doubt it. Beware that the motors are quite difficult to adjust and the fellow who did mine said he wouldn't do another!

Larry

Great .. Now I have something to look forward to....A night of frustration and colorful metaphors.

David

[Inigo]

An useful measure to compare different motors would be to take account of how many spring turns it takes to wind up completely from zero. Not crank turns, but the actual number of turns of the springs. The crank to spring has a demultiplication ratio. I think it could be measured by taking account of the turns of the spring barrels. It can be done observing one barrel and multiply by the number of springs. This is small n. Total number of turns of the springs.
Then we take the time the motor runs down until full stop under no load at 78rpm, so we finally have the turns of the turntable in a full wind down. This is big N.
The N/n ratio would give an idea of how strong the springs are, for we could see here the turns of the spindle for one turn of one spring. Or what is the same, the multiplication that the motor gears have in total from the spring to the spindle. Greater ratio means powerful springs, and longer runs; smaller ratio means smaller springs. It could be interesting to compare different motors by this ratio.

[dzavracky]

An useful measure to compare different motors would be to take account of how many spring turns it takes to wind up completely from zero. Not crank turns, but the actual number of turns of the springs. The crank to spring has a demultiplication ratio. I think it could be measured by taking account of the turns of the spring barrels. It can be done observing one barrel and multiply by the number of springs. This is small n. Total number of turns of the springs.
Then we take the time the motor runs down until full stop under no load at 78rpm, so we finally have the turns of the turntable in a full wind down. This is big N.
The N/n ratio would give an idea of how strong the springs are, for we could see here the turns of the spindle for one turn of one spring. Or what is the same, the multiplication that the motor gears have in total from the spring to the spindle. Greater ratio means powerful springs, and longer runs; smaller ratio means smaller springs. It could be interesting to compare different motors by this ratio.

What a great idea! I think I'll do this when I take the motor apart! Hopefully I can get to it this weekend.

David