Earthing gyrodec

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callaby
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Earthing gyrodec

Post by callaby » 01 Oct 2019 17:04

Looking for any advice or tips from anyone who may be able to point in the right direction to solving my issue. Problem is when I touch the spindle with the clamp I get a horrible static type noise coming through the speakers. Gyrodec with technoarm. I've taken the arm off altogether and took it to my local hifi shop to see if they thought it needed rewiring or repair in some way and they did a continuity test and told me they can't find a problem and the problem must be an amp or something. Cleaned all contacts and topped up oil in bearing re aligned etc hoping id inadvertently solved the prob with the clean etc but nope still bloody their, I can hear a slight crackle when a record is playing also. I'm lost anyone any ideas?

Cyreg
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Re: Earthing gyrodec

Post by Cyreg » 03 Oct 2019 12:31

Maybe it has to do with the earthing (with leads or screws) of the arm and/or platter and/or central bearing with spindle
Can be too much or to little earthing, don't know exactly anymore :(

callaby
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Re: Earthing gyrodec

Post by callaby » 03 Oct 2019 16:57

Hey thanks for the input as far as i can tell its all wired correctly and the two earth cables are attached to the underside of the chasis correctly. When i turn the light switch on or off in room the turntable is it makes a crackle type noise come through the speakers and also a bit of a thump noise through the speakers when the fridge starts up

Werner
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Re: Earthing gyrodec

Post by Werner » 04 Oct 2019 06:42

callaby wrote:
03 Oct 2019 16:57
Hey thanks for the input as far as i can tell its all wired correctly and the two earth cables are attached to the underside of the chasis correctly.
You need to test for continuity from the spindle to the earth tag at the preamp.
When i turn the light switch on or off in room the turntable is it makes a crackle type noise come through the speakers and also a bit of a thump noise through the speakers when the fridge starts up
It is a bad idea to share mains between audio and things lile refrigerators. But in some cases that's all you can do. So this may be sort-of innate to your situation. It may also indicate a problem with the electronics. Do you still have the same with the TT unplugged and the preamp inputs shorted?

callaby
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Re: Earthing gyrodec

Post by callaby » 05 Oct 2019 13:25

Hi Werner thanks for chipping in, the problem seems to relate only to the turntable somehow, when TT is disconnected their is no problem at all. I can’t tell if i can hear interference during record play or not as in i think i can but i may well just convincing myself their is noise because i know something isn't right, it most certainly doesn't sound as rich and pleasing to listen to as it used too, I've recently moved house and put the different sound down to the room being different. new house and new fridge so no thumping in the soeakers anymore when the fridge compressor kicks in but still can hear a crackle type noise when light switch is turned on but only when TT is on. Appreciate any input on this as ive got a growing stack of new records i can’t play and we can all understand of frustrating that is 😩

Cyreg
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Re: Earthing gyrodec

Post by Cyreg » 05 Oct 2019 17:08

Werner wrote:
04 Oct 2019 06:42
You need to test for continuity from the spindle to the earth tag at the preamp.

and…. this above all checked OK than :?:
if you did not you still have to check the complete earth path :!:
...so bearing/spindle to subplatter to armboard to arm to preamp earth...

what phono preamp do you use?
and how is that connected to arm and (pre or int) amp

gwernaffield
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Re: Earthing gyrodec

Post by gwernaffield » 10 Oct 2019 20:11

https://thevinylfactory.com/features...our-turntable/

Hi All after a couple of days messing about and being asked about static,, the pylons are not part of the earthing on a gyro /orbe, i have confirmed this with Michell,, also the use of a ceramic bearing does not add to the static ,
static starts as soon as you remove the LP out of the nice cardboard sleeve ,especially the 180grm stuff , you can try to check this by putting the LP near your arm ,it may lift the hairs with the amout of static it is holding,, here are a list of solutions
1 buy some antistatic sleeves for your vinyl ,
2 check that every thing is tight ,down to the earth screws on the phono stage
3 make sure the earth strap is tight ,
4 make sure that the oil is correct and does not need to be changed or topped up ,
5 if you use a mat make sure it is cork or rubber only about 3 -6 mm thick , rubber 1mm
6 run a continuity test to check all the earths ( ground wires are in tact )
7 continuity to the arm and bearing by adding the earth strap to the chassis or using the stright through bolts,
8 check the belt is not slipping , if you remember from school that this may charge the platter to where you get a static discharge , ( vanden graff generator ) sounds daft but the platter is made of a similar material to the Vinyl )

But all of this starts at the time you take the vinyl out off the sleeve ,
pete

watchnerd
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Re: Earthing gyrodec

Post by watchnerd » 12 Oct 2019 18:41

and using an anti-static brush can't hurt, either.

gwernaffield
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Re: Earthing gyrodec

Post by gwernaffield » 12 Oct 2019 19:25

i use an earthed tranrotor sweep arm , it make no difference , earthed or not ,, brush or no brush ,, if static is there before you start it will be there after you finish ,, a brush is like rubbing some thing on your hair you get static , the same with the supposed anti static brushes, some work and some dont ,, the transrotor was supposed to be earhed but on using a continuity tester it was not becuse of all the clear coat finish ,,2 minutes with a piece of sandpaper and adding a m3 screw sorted that , ,, static ,is with out a doubt strange stuff ,, go months with out any and then you get one that will crackle to death , lol

pete

watchnerd
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Re: Earthing gyrodec

Post by watchnerd » 12 Oct 2019 19:55

gwernaffield wrote:
12 Oct 2019 19:25
i use an earthed tranrotor sweep arm , it make no difference , earthed or not ,, brush or no brush ,, if static is there before you start it will be there after you finish ,, a brush is like rubbing some thing on your hair you get static , the same with the supposed anti static brushes, some work and some dont ,, the transrotor was supposed to be earhed but on using a continuity tester it was not becuse of all the clear coat finish ,,2 minutes with a piece of sandpaper and adding a m3 screw sorted that , ,, static ,is with out a doubt strange stuff ,, go months with out any and then you get one that will crackle to death , lol

pete
brushes make a difference on my system (granted, the static is mild)...the key is to drag the spindle with the brush before dismounting

most of my static is weather induced during the winter

gwernaffield
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Re: Earthing gyrodec

Post by gwernaffield » 13 Oct 2019 15:14

if the weather or the air is too dry i will get static , a zerostat seems to do the job,, with 180grm vinyl being the worst stuff the very thin vinyl i have no problems with at all,, Michell now ground the armboard and arm to the chassis,, this also grounds the bearing ,, all back to ground on the phono/pre amp ,, it happens even if you use the new decoupling kit ,, i added an extra ground back off the chassis to the pre , job sorted,

pete

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