Turntable Right Channel Dropping Out; Grounding Cartridge Body Brings It Back

I have found, over the years and just recently, that hum and signal balance from cartridge pins can be erratic. (or headshell pins other end of short jumpers). A hum can mysteriously disappear, and re-appear.

I have solved things by squeezing female ends with needle nose pliers many times. Snug, but don’t overdo it, because if too tight, too much force is needed to get them on, I just damaged my friend’s pin’s insulation because he squeezed it much too tight with a vice grip (too lazy to go get his needle nose plier).

A firm grip, straight on, good and snug.

Hoping you solve it.

I had a pin break off, I had to solder it back on, and used ’Vinyl Mender’ as insulation, worked quite well. (you might need to magnify your view, try 250%, to see it well enough).

this says ’dries clear and stays flexible’.

https://www.amazon.com/Super-Glue-4332947916-Leather-Mender/dp/B00144CZRW/ref=sr_1_7?sr=8-7

Here’s one for you:

When my friend’s cartridge was erratically humming, then stopped:

I walked slowly toward the TT (on concrete floor, so movement was not involved):

When approaching diagonally from the left side, as I got close, my body effected something, and without even reaching for the arm, the hum started. I repeated the approach, happened every time.

Next, approaching diagonally from the right side, no hum.

I’ve had that happen a few other times over the past 40 years, I once had the sound of a CB radio come thru a receiver when I got in a certain spot, back up, gone, .....

I was drinking a lot of Bass Ale in those days.

@elliottbnewcombjr 

I have solved things by squeezing female ends

You are truly presidential material ...

@oldrooney 

Since the trigger for the fault is the cartridge / head shell interface, I suspect loose connections of the cartridge wires or earthing in that vicinity.  You have made a number of changes, in particular replacing the tonearm cable.  Do you know how grounding was achieved?  Some tonearms have a ground cable for the arm, some use one of the signal wires as a ground.

It seems to me likely that the head shell is grounded, but the cartridge body grounding is flaky.  When you electrically connect the metal cartridge body to the head shell through your stylus brush, your symptoms go away.  You could try removing the cartridge, cleaning its contact area with the head shell, and reassembling.

Most likely you will disconnect the tonearm wires at the same time.  It is worth checking that the female connectors are properly soldered and not flaky.  Don't do this while they are connected to the cartridge, though.

Wikipedia suggests that your head shell is a removable metal die-casting.  That introduces a handful of extra connections to be checked.  Is the collar earthing the head shell to the tone arm clean?

Since only one channel is affected, my guess is that connections downstream from the deck are wired correctly and functioning.  But surely the power amplifier needle should stop moving as you lose sound?  If it does not stop, then diagnosis should start at the right speaker cabling in my opinion.

@elliottbnewcombjr Thank you for responding. You may be on to something. I have tightened the tags (as I think they call them) and I did have a time soldering the new tonearm wires on. It seems some soldering flux wicked itself into the spring-loaded ‘pads’ the cartridge pins contact. The result is that one of the pins on right channel keeps sticking. Befote the stylus brush trick, I was removing the headshell and tapping the tonearm relentlessly before re-inserting the headshell. It usually did the trick for that session, but the issue always came back.
 

I have cleaned the ‘pad’ housing repeatedly with alcohol, and blown it out with air at 150 psi; but I’’m afraid to use anything stronger for fear of damaging the plastic. (My industrial grade contact cleaner warns against using it on plastic, as does the CRC brand contact cleaner available at the local Lowe’s Home Improvement.) I considered contact lubricant, but when I saw mineral oil as an ingredient, again I held off. Thought graphite dust used to lubricate locks might help, but I believe that stuff is very conductive and hard to keep from blowing everywhere. My latest purchase is brake cleaner containing carbon tetracloride— it doesn’t say anything about being a danger to plastics, and I know it cleans the heck out of gummed up typewriter keys. But, again, I’m a little leery of trying it as I fear it might be too strong. 
 

@lewm Thank you for responding. I do have another cartridge, an older Stanton 500 Mark II, but it is mounted in a different headshell. I am loath to uninstall either cartridge as it takes me so long to get the things aligned. I only recently learned that the overhang specified by the manufacturer was provably incorrect. I don’t have a protractor that allows me to confidently set the cartridge at both null points without moving the protractor itself for each null point. I’m considering the purchase of a SMARTracter made by Acoustical Systems, but is twice the price of the new cartridge. I can check my results with the oscilloscope and the test record. But it always seems to take me at least two tries and three hours I’m exhausted and don’t want to go near the turntable for a couple of days. 
 

But now that I’ve finally gotten them both dialed in, I could try swapping the Stanton cartridge in its headshell into the turntable that currently hosts The Vessel cartridge. I can testify that I’ve run The Vessel cartridge in the turntable that currently hosts the Stanton cartridge and it didn’t give me a single hiccup. Again, the troublesome turntable has balanced interconnect modification. The turntable with the original unbalanced interconnect hasn’t given me any problems. But then again, the turntable that received the balanced interconnect modification gave me fits with another Stanton 500 Mark II cartridge: there was a persistent 60 cycle (or 120 cycle) hum, which is why it was set aside to await a the new Vessel cartridge. And, if my records are correct, that is the cartridge I’m now using successfully; because my ‘good’ Stanton cartridge failed under testing. 
 

Yet, as you might glean from my account, there have been so many changes, I may have lost track of them all. It might help to ‘clean slate’ the whole project by removing both the balanced cables and ground switch so that both tables are as similar as possible and take it from there. I was fascinated by the concept of a balanced connection for any cartridge using four (4) pins, but in practical terms I haven’t realized any sonic benefit, and I’m not currently needing the extra length in any case.