mstap42
Active Member
In many threads, AKers have discussed problems with the Philips GA-312's down button, tone arm lift, and auto-shutoff. The problems seem common for these units. A quick survey shows root causes cluster mainly around misalignment of the components in the actuator operated by the Up/Down button. Issues with downstream components are discussed much less often.
I believe my 312 has a new issue. I believe that it has not been discussed here or anywhere else I've been able to discover.
Background
Let me set it up for you with what I tried to do about it back in the day. Or you can just skip down to "the new thing" below.
I bought my Philips GA-312 in the fall of '78. I stopped using it about 10 years ago when the tone arm lift began to trip randomly within the first track or two. Thinking it might be a cueing/damping issue, or something that needed adjusting, I had a technician go through it. He didn't find anything obviously wrong. He made a small adjustment to the auto-shutoff, but there was no significant improvement.
When I got it back, I opened it up to confirm. Everything looked right. None of the standard issues I found here and elsewhere seemed to apply. So when the Down button quit engaging for more than a minute, I shelved my 312. It has been collecting dust ever since.
Recently, I began to think of freeing up some storage space. But I would enjoy using it again if I could find the problem and fix it. The table looks great. The controls feel good to use. And I like the way it sounds with a Grado Red.
The new thing
So I opened it up again hoping to find something I had missed. The common misaligned actuator parts or something else out of whack.
It took some doing, but I believe I found it: simple wear and tear on two actuator parts.
I will add pics from my phone later. I believe they show the parts well enough for you to see the wear I'm talking about.
Here's the deal. The Down button moves a small bit of one metal part to engage with another. Under normal operation, spring-loaded friction holds them together. When the optical sensor trips the solenoid, they are released to the Up position.
From what I can tell, the area where the two parts come into contact looks like it should be about 2 mm wide by 1 mm high. But the parts are worn. The contact area appears to be a little more than half of what it might have been when new. Now there is no longer enough area to give enough friction to hold the parts in place for a minute or two, much less a whole side of a record.
And there is no adjustment.
Options
What about that filing option?
Can y'all think of anything else to try?
Up position
Down position (that little tab is engaged)
That little tab again, in the down position, engaged with the solenoid plate. You can just see some wear on the lower right corner of the solenoid plate.
Side view, down position. Here you can see the worn spot on the lower edge of the solenoid plate (the same corner as in the pic above). I believe I also see some wear on the tab.
Edge-on view of the place in the solenoid plate where the tab engages. Without any wear, it should be a rectangle, the full thickness of the plate. Lower right corner is worn.
A better attempt to show the not-rectangle because of wear. Down position, with the tab under the solenoid plate and behind/away from the worn edge. The right side of that is shorter than the left, decreasing the area of contact needed for the edge of the plate to grab and hold the tab in place.
I believe my 312 has a new issue. I believe that it has not been discussed here or anywhere else I've been able to discover.
Background
Let me set it up for you with what I tried to do about it back in the day. Or you can just skip down to "the new thing" below.
I bought my Philips GA-312 in the fall of '78. I stopped using it about 10 years ago when the tone arm lift began to trip randomly within the first track or two. Thinking it might be a cueing/damping issue, or something that needed adjusting, I had a technician go through it. He didn't find anything obviously wrong. He made a small adjustment to the auto-shutoff, but there was no significant improvement.
When I got it back, I opened it up to confirm. Everything looked right. None of the standard issues I found here and elsewhere seemed to apply. So when the Down button quit engaging for more than a minute, I shelved my 312. It has been collecting dust ever since.
Recently, I began to think of freeing up some storage space. But I would enjoy using it again if I could find the problem and fix it. The table looks great. The controls feel good to use. And I like the way it sounds with a Grado Red.
The new thing
So I opened it up again hoping to find something I had missed. The common misaligned actuator parts or something else out of whack.
It took some doing, but I believe I found it: simple wear and tear on two actuator parts.
I will add pics from my phone later. I believe they show the parts well enough for you to see the wear I'm talking about.
Here's the deal. The Down button moves a small bit of one metal part to engage with another. Under normal operation, spring-loaded friction holds them together. When the optical sensor trips the solenoid, they are released to the Up position.
From what I can tell, the area where the two parts come into contact looks like it should be about 2 mm wide by 1 mm high. But the parts are worn. The contact area appears to be a little more than half of what it might have been when new. Now there is no longer enough area to give enough friction to hold the parts in place for a minute or two, much less a whole side of a record.
And there is no adjustment.
Options
- Reviewing "the literature", I saw a suggestion to add a second spring (for a different issue). Low risk, but probably low reward. Seems like putting more force on an area that already is already slippery has little chance of success. Only one way to find out.
- One guy said he just disconnected things and uses his table full manual. That's not for me. I already have a full manual Rek O Kut with a 12" ROK tone arm. I learned the hard way to never cue it between the start and the runout.
- But I thought of a third possibility. It isn't reversible, but it has a chance: just file the worn part away. Filing the edge back 1-2 mm would be enough to present a larger surface to the part that needs to grab onto it.
What about that filing option?
Can y'all think of anything else to try?
Up position
Down position (that little tab is engaged)
That little tab again, in the down position, engaged with the solenoid plate. You can just see some wear on the lower right corner of the solenoid plate.
Side view, down position. Here you can see the worn spot on the lower edge of the solenoid plate (the same corner as in the pic above). I believe I also see some wear on the tab.
Edge-on view of the place in the solenoid plate where the tab engages. Without any wear, it should be a rectangle, the full thickness of the plate. Lower right corner is worn.
A better attempt to show the not-rectangle because of wear. Down position, with the tab under the solenoid plate and behind/away from the worn edge. The right side of that is shorter than the left, decreasing the area of contact needed for the edge of the plate to grab and hold the tab in place.
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