I went pretty far to get a 830 after reading so much about it. It was my holy grail for a while, so even though the seller was open about "broken foot-pedal", I paid more than for any of my other vintage machines, about $150. I know, still a lot cheaper than what a good machine sells for, I thought I'd eventually come out ahead.
I set it up and found the machine working, but it needs manual starting help - the motor kind of stalls with current obviously running through it. You could see small sparks. I started to suspect the motor, and found two faulty segments on the commutator. It needs a new motor, and I still haven't ruled out possible problems with the control.
It ran well enough to test all the functions, and I fully understand the following this machine has. It sews beautifully, with a very nice sound and feel even though I haven't applied any tlc yet and it had been idle for years. All the functions work, including the buttonholer, flick the levers and go.
Mine is the Record Electronic where speed is regulated entirely with the foot control, as opposed to the Record with a high/low switch on the machine. Electronic controls are expensive, ($175-200), while a generic foot control can be had for $20. I think you're lucky if yours is plain. I ran my findings by an old sm mechanic, and he told me he had found more commutator problems in the 830 series than in any other make or brand! This is limited to the 230 V motors of course, and may not be an issue with 110 V.
I guess what I'm really trying to say is that if your machine is sound electrically, the 830 is definitely a keeper.
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