Vintage DD turntables. Are we living dangerously?

Hi Lewm,

Yes, the platter is stationary where the constant hum is travelled up to the platter mat.

I'm in Canada where 117v is standard. I'm using an Elgar 600A power conditioner adjusted to the unit's minimal output voltage setting of 103VAC. 

There is a diagram on the TT-101 transformer depicting 100vac as primary and 2 x 16.5vac / 1.2a, and 10.0vac / 1.0a as secondaries. 

I've replaced all the capacitors (8 in total) on the PS board in hopes of curing the hum. No luck. However, the speed fluctuation that I was experiencing earlier seem to have disappeared with the new caps.  

Following other TOTL DD designs, I've decided to move the xfmr into an external chassis.  I'll post my results when this is done.   

I'll leave this to JP or someone else with more expertise, but I have to wonder whether using a power conditioner and not per se a step-down transformer could have anything to do with causing the hum that you perceive.  Obviously, yours is a standard 100V unit.

In the longer term, you would want to replace ALL the other electrolytics, as well as those on the Power Supply board.

norm, 

Are you certain the Elgar unit is working correctly?  I see that it's advertised as having sine output.  I'd try a simple step-down as a sanity-check, à la https://amzn.com/B000WMK6QY.

According to the literature the transformer in the 101 is a potted toroid.  If that's vibrating, something is VERY wrong.

JP
 

Dear PJ & Lewm,

A step-down voltage transformer is on order. 

Thank-you

Norm

Tried a new step-down transformer. It is now 98% hum free. A BIG improvement over the Elgar. Which confirms I have a broken Elgar. With ear pressed against the platter mat, I am still able to detect a difference between on/off.

Would other TT-101 owners check this with their units if they can detect any difference between on and off?

Thank you.