I originally posted this on instructables.com but they require membership to see high-resolution images, so I posted it here without ads and restrictions.
Introduction
If you have a Marantz PMD660 CompactFlash recorder, it will probably start to develop an intermittent connection inside the tiny 1/8′ headphone jack. (I work in an institution that owns 8 of them and 5 have needed this repair.) The problem can usually be fixed by re-flowing the solder on the headphone jack and/or slightly bending the contacts within the jack.
In the rare event that resoldering doesn’t work, you’ll need a replacement jack. It is made by Hosiden, part number HSJ1456-010320 (Apparently discontinued sometime before 2014 – no longer in catalog.) The Marantz part number is YJ01080230 but you probably can’t buy it from them unless you’re an official repair facility. (Full Compass used to sell it, but not anymore.) So… good luck!
This guide reveals how to disassemble, repair, and reassemble the machine. It took me awhile to get comfortable with this process, so hopefully this will help somebody get there a little quicker.
You will need basic electronics tools for this project:
- Needle-Nose pliers
- Phillips screwdrivers
- ‘Jeweler’s’ screwdrivers
- Soldering Iron
1: Prepare the Machine
Before you take it apart, find out exactly what the problem sounds like. (How crunchy is the headphone jack? Do you need to flex it to hear the problem?) These things are much easier to diagnose before the machine is in pieces all over your workbench!
Remove the CF card & batteries and get ready to go inside!
2: Remove Screws and Label Strip
Remove the exterior screws (see pics for locations and lengths.) Note that there is one under the warranty label. Yup, you’re voiding your warranty!
Pry off the plastic strip around the power switch + ports. It is glued on, so pry it slowly from one edge.
3: Open it Up
With the unit face-down on the workbench, pry it apart from the jack end. You don’t need to take apart the front face or remove the gain knob. If you encounter resistance, check the adhesive-backed grounding strip (the little flap in the picture, above the phantom power switch). It belongs on the edge of the metal jack-plate, but it often sticks to the plastic case instead, acting like double-sided tape. Use a screwdriver to separate it and groom it back onto the jack plate where it belongs.
Pay attention to the metal rods that support the shoulder-strap. They are held in their mounts by the pressure of the 2 halves of the case. Now they will fall out, so keep track of them.
4: Prepare Main Board for Removal
First, remove 2 more short screws (red circles in the picture below). One will release the ground wire. The other will free the board.
Now, remove the metal jack plate. It will slide out at an angle. (see pic)
Now remove 5 connectors from the main board:
- J113: a 2-pin connector near the headphone jack (wiggle out with screwdriver)
- J110: a 3-pin connector
- J108: a 4-pin connector
- J107: a 6-pin connector
- J33: a flex cable (flip up the black latch and pull out cable)
5: Remove the Board, Do the Fix!
Slide out the main board and rotate it so you can reach the headphone jack. (Be careful with the remaining flex cable as you rotate the board.)
On most PMD-660s the jack was never properly soldered. leading to quick failure. The leads don’t go all the way through the PCB, so the part itself may be to blame. Regardless, most problems are solved by re-flowing a dab of fresh solder on each contact, and pressing a bit from underneath the board to help push the contact through. (Some people have commented that a dab of epoxy around the jack will reduce the physical load on the solder tabs and prevent future problems. This sounds true, but I’m concerned that epoxy will make future repairs impossible so I haven’t tried it.)
I have also seen jacks that needed their internal springs slightly bent to make reliable contact. (sorry, no pic) You can use a push-pin to press through the side of the jack onto the springs. Then they will grab the plug a bit better. For me, this solved a problem where the jack was collapsing both channels to mono whenever it was flexed. (This sounds different than the “normal” failure, where a channel will drop out when flexed.) I have no idea where to get a replacement if you need one, so be careful in there!
Meanwhile, you might want to replace the lithium clock battery if your PMD is getting old. It should last for a few years, but if you’re in there, why not do it?
6: Re-assembly
It basically goes back together in reverse order…
BUT… There is a long flex cable on the bottom PCB that will grab a capacitor on the main board while you are trying to slide it back in place. If you feel resistance, STOP, because it’s easy to pull the hidden end of this cable out of its mount, disabling the LCD and making your life very difficult. A finger or screwdriver will keep it out of the way while you put things back together. (see pic)
Don’t forget those metal shoulder-strap pins. It’s a bit of a balancing act to get them back in place!
That’s it. You did it!
