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Has my Valhalla board died?

naimnut

naimnut

Deep in the Mines of Soul
I've owned my LP12 for nearly 30 years and all that time it has performed flawlessly. I've never heard any speed wobbling or wavering and it has always kept perfect time.

But this morning the thing sounds like it is drunken! It can't seem to keep time at all. Has my Valhalla board died? I believe the belt is only a few years old.

Thoughts?
 
Also, one more thing I noticed - when I stand near the running LP12 I hear a soft ticking sound. I only used to ever hear this sound when it was starting up.

Thoughts? Any LP12 owners (current or previous) have experience with this?
 
Yes, the Valhalla is poorly - but it can be fixed.

Having said that, the ticking sound is unrelated. Either it is the motor pulley catching on the underside of the platter (invert the outer platter and run to see if this is the problem), or you have an early motor thrust pad, a grey cylinder attached to the underside of the motor - just pull it off if you have one of these - this will stop then ticking noise but won’t solve your larger problem.
 
Obligatory warning if you plan to have a look inside: if a Valhalla board is plugged into the mains it is ‘on’ regardless whether the deck is running and parts of the board are live 240V, i.e. unplug the deck before going in!

PS Don’t ask how I figured this out...
 
Err.... yes... don’t prod inside the plinth if the power supply/deck is plugged in. If you touch the Valhalla (whilst the mains is on) you will get a hell of a jolt (if you have a dicky heart I guess it could kill you)!
 
Wimps. I poke around live 3 phase stuff every day, you should see some of the craters in my multi-meter probes!
 
@Tony, I’ve made contact with the Valhalla board a couple (perhaps three) times and it does send your whole arm into spasm - I didn’t die though (or did I .....).
 
if its the same tick tick as you get at startup that's actually caused by the motor failing to make the next 1/24 th revolution on time because it's under load.

It suggests that the motor might actually be sticky, which is a known issue with the old top hat type. The grease can actually set causing the motor to jam.

The fix is to pull off the top hat and either re-grease it and put it back, or just throw it away.

a drop of 3 in 1 oil can also help.

Its actually very hard for a faulty valhalla to produce wonky speed stability, far more likely to be slipping belt or sticky motor issue.
 
Yeah. I threw the whole deck across the room once. Destroyed the plinth. Hell of a shock. Never did it again though.
 
Replace the big caps as a preventative measure and replace the scorched resistors with higher wattage types and lift them 5mm off the board. Leave them to discharge before soldering the old ones, you can guess how I know.

A couple of drops of light oil into the motor then lift the shaft and twist a few times and leave the oil to make it's way down.
 
Symptoms suggest motor bearing stiction which indicates a motor bearing flush and oiling as being necessary. Specifically, throughly clean the top and bottom motor bearings with IPA and let dry before oiling with one small drop of motor oil into where the motor spindle meets each motor bearing. This is more easily done with the motor removed from the deck, but the bottom bearing can be accessed in situ with the main platter bearing well capped and the deck upside down. You'll have to pull off the bottom thrust bearing cap/assembly, if present. An eye dropper or syringe is ideal for the bearing flush. No amount of IPA is too much, just make sure to allow it to thoroughly evaporate before oiling.

As to choice of lubricant, I've used SAE20 oil (often sold as 'electric motor oil') to good effect for decades. Rega recommend 20W/50 hyper- or multi-grade for the same Philips/Airpax/Premotec motors.

P.S. I had originally attempted a link to a copy of Linn's 'LP12 Motor Flush Instructions' (LP12_tech-motorflush.pdf) but mine seems to have gone AWOL during a recent cloud move. Anyone have a copy to share?
 
Rather than start a new thread I thought I'd add to this one.

sq225917 said:
A couple of drops of light oil into the motor then lift the shaft and twist a few times and leave the oil to make it's way down.
Click to expand...

I noticed that the motor on my LP12 was making an unusual ticking, chugging noise. First thought was the new DIY Zeus motor PSU, so I messed around with a few of the drive voltage settings, but the noise was stubbornly there.

A couple of drops of sewing machine oil, through a syringe, into the top bearing, lift and spin...and the noise is gone. The motor is back to being completely silent.

Handy tip.
 
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