VV 4-7 Issue

[CharliePhono]

I wasn't sure whether to call it "tone arm sticking issue," an "auto-brake issue," so elected to go with just "issue." My 4-7 is the "daily driver" in my little house, and while some will disparage its tiny Orthophonic horn and label it inferior to other, larger (or metal-horned) units, it suits the space just dandy. However, I've noticed something recurring with annoying (and hazardous to records) regularity which is a first for me, and I'd appreciate some input on this.

I noticed during play that records, which had never skipped before, have begun to do so. You know, the old, annoying "broken record" scenario where the needle sticks in the groove and keeps repeating. When this began happening on my cleanest discs, I knew something was up. I have a theory, but wanted to run it by the forum. It is to note that the tone arm travels very smoothly without binding when not playing a record. Thus, I was thinking this might perhaps have something to do with the auto-brake? It will occur randomly, but generally always about the middle of play or within perhaps a minute of completing play. This machine has been nicely refurbished, complete with a MicaMonster soundbox and, again, everything is fluid and well lubricated.

Do you think this has something to do with the brake or is it another issue entirely? I can't let the gremlins take my main source of entertainment away, so any help is greatly appreciated!

~ CharlieP

[EarlH]

Disconnect it and see if that solves the problem until you can fix the brake. Sometimes those springs have been tampered with and are too weak or pulled to be too strong. You might have to move that ratchet pad some on the brake as well. I've had them come up against the click dog harder than they should and then they will shut the thing off with the slightest little bit of 'wow' on the record. One of the bearings in the tone arm might have a flat spot on it too, or a bit of dirt down in there will do the same. Good luck with it now. Earl.

[CharliePhono]

Disconnect it and see if that solves the problem until you can fix the brake. Sometimes those springs have been tampered with and are too weak or pulled to be too strong. You might have to move that ratchet pad some on the brake as well. I've had them come up against the click dog harder than they should and then they will shut the thing off with the slightest little bit of 'wow' on the record. One of the bearings in the tone arm might have a flat spot on it too, or a bit of dirt down in there will do the same. Good luck with it now. Earl.

Thanks, Earl; I appreciate it. I will do that (disconnect the brake) and see what happens and report back in a bit. And since you mention it, I have indeed noticed that a disc with even the slightest amount of "wow" will trip that brake. It's hugely annoying, since it usually occurs on a tune I'm really enjoying, it seems.

If the issue occurs with a disconnected brake, the next thing will be to examine the whole tone arm and its support mechanism, as you suggest. I will say that is the one part that was not opened up and cleaned thoroughly as, at the time, I had a fear of tampering with the original tone arm support, which is exhibiting some fine (the usual) pot metal crazing. I'll let you know what happens.

[EarlH]

Get a new tone arm support. You know, a crack in the base of the pot metal will hang up one of the bearings too. You'll be a lot happier with the machine if you don't have to worry about that thing snapping off. It seems like the last one I bought was around $80. You'll have to break the old one out of the support though since they will usually swell into that steel ring pretty tightly. In a small space, those 4-7's sound pretty good. I had a 4-20 for a long time and was very happy with it.

[CharliePhono]

I actually do have a new support that I bought at the same time I got the 4-7. The reason I haven't installed it is because the old support is in amazingly good condition. There are no wide or gaping cracks to speak of, only the very slightest light crazing and that is not all throughout the thing. The tone arm moves very well and smoothly in the base and is well supported without any up-and-down wobble.

[CharliePhono]

Ok, test done with auto-brake disconnected. Tried the former records which skipped (and they skipped in the exact same spots; on inspection, at least one of the records has a worsened dig in the grooves). I used medium tone (original NOS Victors) and soft tone - all skipped. I then tried the records on a different machine, and setting the reproducer down in the same spots yielded no skips.

Would this then indicate a needed tear-down of the tone arm assembly as well as replacement of what appears to be a good back bracket? I use this machine heavily, so I'm thinking possibly "yes" to that question. This is all very new and, except for the auto-brake being *very* sensitive to any wow at all on a disc, the sticking/skipping has never been an issue. What is odd to me is that when I would lift the reproducer off the record at the point of skipping and move the tone arm side to side, there was no evidence at all of any binding of any sort.

[CharliePhono]

At this point I can answer my own question, and perhaps it will be of some use to someone down the road.

The problem was being caused by a the back of the tone arm not being secured by the support bracket pin. I noticed during the record-playing trials, searching for the sticking, that the tone arm could be rocked up and down, as the pin was not securely seated in the divot at the upper back of the tone arm. After some gentle manipulation and moving the pin downward (but while the arm still traveled smoothly) and tightening, the problem seems to be solved. I played the machine for over an hour last night with no issue.

That was a first for me, and had I not noticed the problem with that pin, I likely would still be looking for the cause of the sticking issue. Thanks to all who contributed.