Can magnet placed beside cartridge damage a coil?


I received a 20 year old NOS cart from a dealer which I resold as new but ended up having to refund the payment back to the buyer after he found it to have a channel imbalance issue.

I sent it back to the dealer to check out and he says there is a large difference in coil readings of 1.3 (normal) vs. .8. He says he tested his entire stash of these old carts prior to selling them and says the only explanation is that somehow a magnet was placed close to the cart either during transport or by the person I sold it to and thereby damaging the one coil. He therefore assumes no responsibility to replace it.

Would this be possible?
frankk
A high energy magnet would ruin the cartridge by demagnetizing the cartridge's magnet which folows as to your description of the problem. Moving magnet cartridges need both sides equal - equally muscular magnet - to get proper balance.
He tried to re-energize it by running current through it with a small 9vdc battery but it did not work.
I sure hope that he had a suitably chosen resistor in series with the battery. Otherwise I would expect doing that to result in the 0.8 mv becoming 0.0, permanently!

Regards,
-- Al
Is the dealers name 'Joe Isuzu'? "Yeah the ol magnet trick thats what it was!"
The more I think about it along with all the responses here leads me to believe the possibility of a misplaced high strength magnet somehow mistakenly de-energizing one of the coils partially vs. the 20 year old cartridge having been faulty in the first place lends me to conclude the latter.