Compact Mac Screen Width Adjustment Tool

[just.in.time]

Hi,

To adjust the screen width of a compact Mac, you need a plastic hex tool (as the adjustment at L2 is a ferrite core, etc etc).

I want to order the tool, however I can't find what size the tool is.  Hex tools are usually measured in mm or fractions of an inch.

Does anyone know the correct size?

Thanks

 

[techknight]

I always used chopsticks. They seem to work ok. 

As far as the actual slug adjustment tool set, I have no idea. Back in the day they used to sell those kits for servicing radios and TVs, but they seemed to have vaporized. 

 

[apm]

I have used a wooden kebab skewer with some success.

 

[just.in.time]

Okay.  Found some TV adjustment kits on Amazon for around $13.  If the chopsticks idea fails, I may drop an order in for that kit.

I tried the plastic end of a paint brush that I had taken some sand paper to, but no go.

It almost seems like the ferrite core is jammed in place.

Should I try taking a hair dryer to that clear plastic tube to see if it will help loosen?  I'm slightly hesitant to apply heat to that area with the two capacitors immediately next to it.

 

[just.in.time]

Went and got some Panda Express to get some chopsticks.  I sanded them down to size, and they get good grip.  However, that core is locked in tight.

I set my solder rework station hot air gun to the lowest it would go (212 degrees F) and tried heating the plastic tube for a minute, but still no give :-/

Any ideas?

 

[trag]

Sheewww, that's likely a bad situation. Those cores are hard to impossible to unstick. We had a long discussion around here a few years ago about L2 and maybe making replacements.

 

[just.in.time]

I think you are right trag.  Its starting to look like it is breaking apart inside the clear tube.  That's unfortunate.  Despite that, it also doesn't look like it will be easy to just break apart and clean out.

Is that whole assembly for L2 (the clear tube, the ferrite core, and the wound wire at the base) replaceable?  If so, can I swap it for the equivalent part on a Mac Plus analog board?  Or do I need one from the SE line?

 

[nvdeynde]

The ferrite cores are very fragile. It's best to adjust them only if it's really necessary like after Flyback replacement.

The part is the same in Compact Macs  from an 128K to an SE/30 as they use the same flyback.
I've exchanged them with success between these boards. Haven't tried it with the Classic I/II as they use another Flyback. 

I adjust them with a standard metal throrx screwdriver, but with the Mac turned off during adjustment. Otherwise the screwdriver will get very hot in just a few seconds and damage the ferrite core.

 

[techknight]

If it wont move, tis because its already cracked. someone may have tried to twerk on it in the past and broke it. 

 

[just.in.time]

That honestly wouldn't surprise me. The previous owner also had the speaker hooked up reverse polarity (they had to physically force the connector), among other odd decisions.