ARCHIVED FORUM -- March 2012 to February 2022READ ONLY FORUM
This is the second Archived Forum which was active between 1st March 2012 and 23rd February 2022
Hi there!
I am dealing with a BeoGram 1200 that only plays in the right channel. I have tried with multiple pickups (2 x SP7, 1 x SP14), without any changes.
I have cleaned the motor and all the contacts but i am in doubt that the contacts and switches are as they should be. It looks like someone has been trying to fix it before me.
I've checked all the wires in the tonearm and the DIN-plug and everything seems to be alright.
I've attached some images - maybe someone can tell me if someting seems of?
Kind Regards,
Christian Leicht
https://leicht.io - B&O Custom Parts & 3D Models
Check that RIAA socket.It seems to be heavily oxidated, and the signals run through it - to be interrupted when a RIAA module is plugged in.
Martin
I didn't know that the black part of the surface was oxidation.
Is it possible to remove?
Pull a piece of paper soaked in contact clener between the contacts.Or, even better, take it apart and clean it all using a glass-hair brush.
Hi again Martin and thank you for your help.
I cleaned the contacts in Beauvais ketchup which removed all the black oxidation - the smell was horrible. I will add some pictures later. This fixed the problem with the dead channel. Ketchup = multitool!
Unfortunately, there is now a constant hum in the background, even when playing a record. It sounds more like a high frequent hum than a problem with ground. I will check the grounding when i get home, but maybe someone know if anything else can cause this hum?
Ketchup?..
Yes, it is an extremely effective method in cleaning metal due to the properties of the ingredients in it. The acetic acid attacks the surface and removes old oxidation. The pH is around 3.8-3.9 according to my litmus test paper.
Some images after cleaning: