Alps, Munich

Restauring an old iRiver iHP-120, Part 1

In a time before smartphones, people used so called "digital music players" for portable music. One of them was the iRiver iHP-100 series, which came to the market in October 2003. It had up to 40 GB of storage, which was really a lot these days. It had a playback time of up to 16 hours. It had a remote control with a separate display. And it is the only pocket-size player I know that is also equipped with an optical line-in and line-out.

I got my player in 2004, and I used it for many years, until the hard disk started to show first signs of failing. Then I stored it away to save it for "special occasions" that never came. Many years later, I did not dare to charge it again, as I distrust over-aged Li-Po batteries that have been discharged for a long time. So my player became a Sleeping Beauty, waiting for the day it would be rediscovered and properly restored. The day was now.

In this first part, I will replace the original battery. In a second part, I will replace the 20 GB hard disk with a modern 128 GB MicroSD card, which is a lot more than the size of my entire music collection. After more than 16 years, it will be a modern portable music player again. (Well, sort of… I know it's still inferior to a smartphone.)

Before we start: Li-Po batteries are delicate. A damaged battery can cause severe damage to your home and your health. Please be very careful. If you're not confident enough for the operation, please ask someone for help.

The player is opened by removing the eight screws from the top and the bottom cap with a T6 screwdriver. The caps are glued in place, but can be pulled off with a bit of force. After that, the back cover can just be lifted off. The attached battery cable is very short, so be careful when lifting.

This is a photo of the inside. To the left is the battery pack that we are going to replace. To the right, we see the 1.8" HDD. Yes, the iHP uses an actual hard disk, with spinning platters and arms and all. In part 2, it will be replaced by a MicroSD card.

The battery connector is on the other side of the PCB, so we have to disassemble more. First we remove the HDD, it just needs to be gently lifted and then pulled out of the connector. There is a screw on each of the two side panels, they need to be removed as well. Then we remove all visible screws on the PCB.

The display frame is glued to the front cover, so we need to use a bit of force to remove the PCB. Be careful, the display is very sensitive to scratches. Also we don't want to have hairs and dust caught between the display and the front cover when we reassemble the device, so make sure you work in a clean and dust-free room.

Now we can disconnect the battery from the main PCB. Sadly, the power connector is in the way, so we need to twiddle with the connector and use a bit of force to get it removed. If you use a screwdriver, take care not to slip off and damage the PCB. Also, take care not short circuit the battery cable.

In the next step, we can remove the old battery pack. It is glued to the back cover, so we need a lever tool (e.g. a plastic opening tool) and some patience to gently remove it.

Be very careful when you remove the old battery pack. Do not use blades or pointy tools, and do not use force. The battery pack may burn if bent, damaged, or punctured.

You got the old battery removed now? Please don't just throw it away, but make sure it is properly recycled.

Before we insert the new battery, we should have a look at the cable first. On my replacement, the cable was considerably longer than the original one, so I decided to align it with the other corner of the back cover. If your cable is shorter, or if you are not sure, use the same corner as the original battery. In any case make sure that the cable is at the bottom edge of the back cover. If there is some of the glue tape left, it will firmly hold the new battery in its place.

If you think it was difficult to disconnect the old battery, you will find out that it is even more difficult to connect the new one. Check that the polarity of the connector is correct, the black wire must be closer to the USB connector than the red wire. Take care not to cut or break the wires while inserting the connector. If there is absolutely no way to push the connector into the socket, you need to remove the USB daughterboard. It can be unplugged after unsoldering the wires on its four corners.

I was lucky. After a few attempts and some frustration, I finally got the new battery connected.

When reassembling, make sure the battery cable is correctly routed like in the next photo. It must not be pinched anywhere. Now the PCB can be placed back onto the top cover again.

This is the right moment to check if there are visible dust particles or hairs caught between the display and the front cover. If so, use a photo lens brush to gently brush them away. Do not use a cloth, as it may cause tiny scratches.

Now close the bottom cover for a test. The battery cable should fit properly and should be tension-free.

After that, you can reassemble the device in the opposite order. Congratulations, you have given a new life to this amazing piece of hardware!

In the next part, we will replace the HDD with a MicroSD card. It will not just conserve some battery power, make your player faster and keep it cooler, but also greatly extend hard disk space for your music.

Reviving a Sony CDP-991, Part 5

The player is playing again. Time for some final cleanings.

Fifth Problem: Crackling Volume Pot

The volume assembly with the pots on the left. Just spray into the hole. After the calibration part, this is going to be a walk in the park. Or so I thought.

On the CDP-991, the playback volume can be changed via remote control. There's a motor that actually drives the volume knob and the potentiometers. The custom file feature allows to store individual volume settings for different CDs.

Due to the construction with the pots and the motor, the volume control assembly is rather big and is mounted to the front panel with screws. I removed the screws and the volume knob, but still could not remove the assembly for cleaning. It was still fixed somewhere else. The service manual gave no hint about how to remove it.

So I just tried my luck and sprayed some contact cleaner into the holes of the three pots close to the front. It worked, and saved me from finding a way to remove the assembly.

And that's it... I closed the case and polished it with a microfiber cloth and a soft cleaner. Then I put batteries into the remote control.

Welcome back to the living room, my good old CD player! 😀

Retrospective

Looking back, I am surprised how much is still working and in a good shape after 27 years. I am also surprised that I could still get a good service manual, and all the necessary replacement parts.

For most parts of the restauration, I just needed a screwdriver, cotton buds, isopropanol, and grease. So basically it can be done by anyone who isn't all thumbs. Just the pickup replacement and the calibration needs more elaborate equipment.

Reviving a Sony CDP-991, Part 4

The CD player finally plays music again, but still has trouble with the higher tracks.

Fourth Problem: Worn out Laser

Let's find out how worn out the laser actually is. I soldered a wire to the RF test point and connected it to a scope.

The service manual recommends to use a special test CD, but you can use any CD for the RF test. I found out that older CDs gave better results, probably because modern production methods are cheaper and less reflective. Do not use CD-R, as these discs use a dye and are not as reflective as standard CDs.

According to the service manual, the signal should have an amplitude of about 1.2Vpp (+0.2V, -0.4V).

The actual amplitude is just above 600mVpp, far below the required minimum of 800mVpp.

The first thing one should try now is to clean the lens. I used a cotton bud and 100% isopropanol for that. After that, the amplitude was a little better with about 880mVpp, but still at the minimum.

I could now recalibrate the player and try to get the best out of it.

But honestly, a new optical pickup module for this player can be ordered at the Bay for less than €20. It's not genuine, since Sony is not producing the KSS-240A any more. But I am curious how good that remake actually is. If it should be worse, I could still continue to use the original one.

The optical pickup is very sensitive to static discharge. If you try the replacement at home, use an antistatic wrist strap and other ESD protective measures while handling it!

The replacement of the pickup was much easier than expected. Only a plastic clip is holding the metal shaft of the sled in place, so it could easily be pulled out. After that, I could remove the old pickup.

And while I was at it, I thoroughly cleaned the shaft and the plastic parts from the old grease again, and reapplied a bit of fresh silicone grease. I also applied a little bit of grease to the gears that are moving the sled.

Then I inserted the new pickup and fixed it with the shaft. The first test with the new pickup brought good news, and bad news. The good news is that the replica pickup is working, and the RF amplitude is even above the 1.4Vpp upper limit now.

The bad news is that the drive was making a loud and awful whistling noise now. So I recalibrated the player as described in this restauration project of a similar player.

The calibration was successful. The whistling noise is gone (except on track changes), and the player plays all the tracks again. I am sure an experienced technician can calibrate it a lot better, but I'm happy with the result.

And thanks to my proper cleaning, the sled noises are also much better. By all means good enough considering the age of the player.

I'm almost done! There's just a tiny problem left: The crackling volume pot.

Reviving a Sony CDP-991, Part 3

In the last part, I made the tray operational. It's a precondition for this part: Inserting a CD.

Third Problem: Stuck Sled

In the opened tray, I put a random CD from my shelf. Then I pressed the close button. The tray closed, and a few seconds later, the player showed the number of tracks and total playback time. Yaaay! 🎉 The optical pickup seems to be working.

Daringly I pressed the play button, the disc started spinning, and then...

Nothing. No playback. Just silence.

I also noticed that the characteristical noise of the moving sled was missing when I changed through the tracks.

My first thought was that the laser was worn out after all. But then, on the other hand, the pickup would not have been able to read the CD's table of contents. It rather seems that the sled was stuck.

The optical deck with the pickup on the sled I disassembled the drive again. The pickup moves on a metal shaft and a plastic strip. Both were greased. I carefully removed the old lubrication with cotton buds and isopropanol, then applied a tiny bit of fresh silicone grease.

Next attempt... And this time, it was successful! After about 15 years, I heard music from my good old CD player again!

But I'm not done yet, as I already spotted some more problems. The player refuses to play higher track numbers, and the sled is still making strange noises on a track change. Also, the volume potentiometer crackles awfully and needs some cleaning. More of that in the next parts.

Reviving a Sony CDP-991, Part 2

In the first part, I powered up my CDP-991 again after 15 years. Next step: Open the tray.

Second Problem: Weak Tray Belt

The replaced tray belt I pressed the "open/close" button, and the tray opened. I pressed the button again, and the tray closed. Almost. After a few seconds it opened again. Obviously, the mechanism got too weak to completely close the tray.

The exploded view in the service manual revealed that the tray is moved by three gears and a belt. I removed the drive and then the tray, to expose the tray belt. Indeed, it got flabby over the years.

Warning: There are live parts inside the case. Before opening it, always unplug the power. If you are going to plug in the power while the case is open, always take appropriate measures to protect yourself from accidentally touching live parts. If in doubt, better ask a trained person for help.

It was easy to find a new tray belt on the Bay for just a few euros. I ordered one, and it was already delivered the next day.

After replacing the belt and assembling the drive, the tray finally opens and closes now. It is a clever construction. The top gear moves the tray. When it is almost closed, the gears are pushed sideways and turn the cam below (the silver part in the photo). The cam pushes up the optical deck and clamps the CD to the spindle. This part of the movement takes quite a lot of force. Too much for the old and worn-out belt.

It is a good idea to replace the belt on spec, after all those years. If the tray still won't close, the culprit might be the switches on the tray motor assembly. On the photo, you can see their "tongues" to the left and right of the motor. These switches detect when the tray is fully opened or closed. The contacts may have become dirty over the years, and just need some cleaning. Since my player's tray is operating normally now, I postponed this "fun" to a long and boring winter's day. 😉

The next step is critical. Is the laser pick-up still operational after all those years? Let's find out! I'm going to insert a CD.