Chrysler 8-Track Stereos
by Jeremy Schrag
The 8-Track. For a good many of us, the term conjures up memories of the 1970s, when we rushed down to the local record store to grab the newest Bee Gees release. I'll confess right now, I was only a very young child back then, so I don't quite have the memories of this format that others may have.
The 8-Track, or "Stereo 8" as it is more properly called, actually predates the seventies. Developed as a format in the sixties by Richard Kraus for a group of people led by Bill Lear (of Lear Jet fame), it was an evolution of an older technology sometimes called the 4-Track.
As you can see above, I'm looking at one of Chrysler's late seventies entries into the 8-Track format. I've stolen the knobs off a newer Quartz Lock deck for this picture, as this deck from a Cordoba didn't come with any knobs. You will see four red arrows in the above picture... those indicate the metal clips that hold the face on. I'll address those in a bit.
But before we go on, you younger folks might be wondering how a clunky format like the 8-Track ever became popular. I mean, we've had cassettes since the sixties, right? That's technically true, but you have to consider where we were technologically. Most electronic devices of the day were simple in construction, so they could be made cheaply using the tools of the time.
The cassette was not cheap technology, because the mechanisms were complicated. The tape was very small compared with 8-track and open reel tape, and it passed the heads slowly, leading to poor fidelity (because there was very little tape being read at any given time). At the time, cassette decks were complicated, expensive, and didn't sound that great. The cassette had a hard time until better tape formulations, electronics, and mechanisms arrived in the mid-to-late 1970s.
In the sixties, manufacturers needed something portable and easy to use, far less time and space consuming than the open reel tape used by audiophiles. The continuous loop tape cartridge was the answer, which evolved into our 8-Track format. With this technology, the cartridges could be put together cheaply; and the decks were decidedly uncomplicated even for the time. You could have your tunes for a low price. That's how this format took off, folks.
Before we dive into the 8-Track format in more detail, let's get this deck apart, shall we? We'll need a 1/4" nut driver to get into this one. Blue screws indicate two of the bottom cover screws... the 8-Track module is bolted to this cover inside. Orange arrows show you two of the screws holding the front face on.
Look what we have here (above), indicated by the red arrow. A damaged wire. In fact, this is the illumination wire. If I were refurbishing this deck, I would have to address this with some heatshrink tubing.
The back panel. Blue again indicates the bottom cover screws, while red shows you the top cover screws. We'll leave the remaining brass colored screws alone - they do not need to be removed to service this deck.
Note the presence of the smaller metal screws with the slotted heads near the blue arrowed screws - these help to hold the 8-Track module to the bottom panel. We'll get to those later.
Here's the connector shot for this deck. Too old to get the black and gray connectors Chrysler decks of the eighties, this deck is much easier to figure out. The white connector is the speaker output harness. One ground wire, four positive wires. This is a common ground deck, as many Chrysler decks were up until about 1984.
Of the two remaining connectors, the big black one with the red wire is the 12 volt power to the deck, while the orange one is, again, for the illumination.
The other side of the deck. Blue for the bottom cover, red for the face
This is the top of the deck. There's only one item of note here, arrowed in blue. This is the illumination lamp holder, and it is held in by the snap arrowed in red. It's just like the snaps on your winter jacket. To replace the single illumination lamp, you must release the tabs on the side holding the orange wire to the case, undo the snap, and pull the lamp holder straight up and out. It couldn't be much easier.
The bottom cover. All three bronze screws you see here hold the bottom cover to the face.
In all, there are nine screws holding that bottom cover on. We're going to take them all out now and have a look inside the deck for the first time.
The deck folds open like this, so that you can detach the 8-Track module connector, arrowed in blue. It's friction fit, so all you need to do is pull the two halves of the connector apart.
This is what the 8-Track module itself looks like. Most operate pretty much the same way. The cartridge slides in and pushes on the lever arrowed in black. This tells the mechanism to turn on. Since the tape cartridges themselves have the pinch roller, we don't have to worry about one of those here today. This was, in fact, one of the ways they saved money on this format. Because the cartridge has the pinch roller, there is no need to add a mechanism to move one or two into place, as we see with cassettes. (Editor's note: this no doubt added cost to the cartridges, but since those were made by different companies and the cost was passed to the end user, it presumably was still considered a savings.)
You're probably wondering what the other arrows are. Orange is the capstan, which is frequently an issue in 8-Track decks. They wear down with heavy use. (Editor's note: they also tend to get covered in media from the tapes, which makes them sticky; that can be removed with alcohol and a cotton swab.)
The red arrow is a special set of electrical contacts. You see, because the 8-Track tape is one continuous loop with eight tracks, arranged on top of each other (leading to four stereo "programs" on each tape), they had to provide a way to tell the deck when to switch to the next set of tracks by moving the head up or down. This was done by splicing the continuous loop together via a metallic strip. When that strip met the red arrowed contacts, the deck fired that big solenoid on the top right, causing a loud "click," and the tape head moved up or down to the next set of tracks. (With auto-reversing cassettes, the head also moved up or down to get from one set of tracks to the other.)
This was, in fact, the cheap way to do it. More expensive 8-track machines sometimes had a head that could read all tracks at once, and did not require moving, but as yet I have not seen one built like that. This is probably because that anyone who would have been interested in such an improved 8-track deck was likely already enjoying open reel tape technology at home, which is by leaps and bounds superior to all other audio tape formats save for perhaps DAT (digital audio tape) or DCC (digital compact cassette). Pay extra to make the 8-track format sound only a little bit better but still worse than open reel? Most people likely preferred the affordability of the moving head mechanism. They had their turntable and expensive open reel machine at home, if they wanted sound quality.
And really, affordability is what brought the 8-Track to the dance. You couldn't rewind them, due to the way the continuous loop tape is wound. You could barely fast forward them. Only a few decks could ever record to them. The 8-track really was a "well, it's better than humming to myself while drumming on the dashboard" option. Records didn't work as a portable format, though Chrysler tried them for a while. Ditto for open reel tapes, though many companies tried to make them portable. The cassette was mediocre and expensive. What else were you going to do for music on the go back then?
Let's move on, and remove the mechanism from the bottom cover via the blue arrowed screws.
Now we can access the drive belt for the mechanism, and this one has seen better days for sure. On cycling it by hand, I can see a clearly deformed spot in the belt, and the rubber has gone hard. This belt would not last long were I to actually use this deck.
Be careful when you remove the belt on this deck - the flywheel on the right, which drives the capstan, is just sitting in there. It and the capstan will fall out if you're not careful and turn the mechanism over without the belt in place.
In fact, I'll even remove it for you, to show you the wear on the capstan. This deck has played more than a few 8-Track tapes.
The section of the bottom cover where the flywheel rides has a special greased bushing where the shaft sits. If you are refurbishing one of these, make sure you clean up the old grease and apply some new white lithium grease. This deck is more than thirty years old, and so is the grease.
Now, we'll have a look at the rest of the deck, which is refreshingly uncomplicated compared to many of the newer units.
This is what you see when you pull the top cover off, and the insulator found below it. Now, you can inspect the solder joints.
Removing the front face is a little tricky, but we'll do it. Remember those four rusty clips I showed you in the first picture? Pop those out now, and pull the front panel off like so.
The red arrow indicates the illumination lamp bracket. Let me pull that out and I'll show you that now.
The single illumination bulb in this deck is a simple 12 volt bayonet base affair with a blue filter sock over it.
To get the front face housing off, there are a few things to do. First, there are two black plastic bezels over and beneath the tuner indicator to remove. Those are just clipped on. Remove them carefully, so that you don't bend the tuner indicator.
Then, remove the three screws arrowed in blue and pull the entire gray housing forward.
This is a view from behind. Before the front face will come off, you need to unplug the connector arrowed in yellow. Remember which way it goes on. Blue arrows show you the catches for those black plastic tuner bezel pieces - if you're having trouble getting those unsnapped, press against them from this side.
Now... you need to move the tuner indicator so it doesn't catch on the face assembly. Use the tuning knob to move the pointer in the direction indicated by the long red arrow. Move it all the way over, until it lines up with the slot represented by the short red arrow. You can then pull the face off.
Note that the balance control will still be wired up, but those wires should give you enough room to pull the face off.
There... the face is off and we can get into the insides a little easier.
If you are restoring one of these decks, I'll give you a few tips. First, replace all the electrolytic capacitors... in this deck, the ones in the black cans. Replace every last one. Capacitors have a finite life span, and these are almost as old as I am. It is very common for these to have failed by now.
Also clean the potentiometers (the parts that do the work of the knobs) on the top right with some electrical contact cleaner and lube. You can get some at Radio Shack, or your nearest electronics supply store. The one on the very end toward the top middle of the picture is actually the rotary power switch for the unit, which doubles as the switch used to change tape programs, when you push down on the volume control. You likely won't have to do any cleaning there, unless functionality is intermittent. Just make sure you get the four directly in front of it - those are the volume and tone controls. Clean the balance control on the face while you're at it.
Red arrows indicate the two amplifier chips for this deck. You will likely not find replacements for these anywhere, but they are Hitachi 7280s just in case.
Finally, here's the tuner and preset mechanism. This operates like most other mechanical tuners of the day... pull the knob out, dial up your desired station, then push the knob in to hold the preset.
This concludes my look at what is now the oldest car stereo in my collection. I hope you've enjoyed this look into the past as much as I have, though I confess that when cassettes exploded in the eighties my last thought for the 8-Track format was "good riddance." I couldn't wait to be rid of them. But those really were the good old days, weren't they?
by Jeremy Schrag
The 8-Track. For a good many of us, the term conjures up memories of the 1970s, when we rushed down to the local record store to grab the newest Bee Gees release. I'll confess right now, I was only a very young child back then, so I don't quite have the memories of this format that others may have.
The 8-Track, or "Stereo 8" as it is more properly called, actually predates the seventies. Developed as a format in the sixties by Richard Kraus for a group of people led by Bill Lear (of Lear Jet fame), it was an evolution of an older technology sometimes called the 4-Track.
As you can see above, I'm looking at one of Chrysler's late seventies entries into the 8-Track format. I've stolen the knobs off a newer Quartz Lock deck for this picture, as this deck from a Cordoba didn't come with any knobs. You will see four red arrows in the above picture... those indicate the metal clips that hold the face on. I'll address those in a bit.
But before we go on, you younger folks might be wondering how a clunky format like the 8-Track ever became popular. I mean, we've had cassettes since the sixties, right? That's technically true, but you have to consider where we were technologically. Most electronic devices of the day were simple in construction, so they could be made cheaply using the tools of the time.
The cassette was not cheap technology, because the mechanisms were complicated. The tape was very small compared with 8-track and open reel tape, and it passed the heads slowly, leading to poor fidelity (because there was very little tape being read at any given time). At the time, cassette decks were complicated, expensive, and didn't sound that great. The cassette had a hard time until better tape formulations, electronics, and mechanisms arrived in the mid-to-late 1970s.
In the sixties, manufacturers needed something portable and easy to use, far less time and space consuming than the open reel tape used by audiophiles. The continuous loop tape cartridge was the answer, which evolved into our 8-Track format. With this technology, the cartridges could be put together cheaply; and the decks were decidedly uncomplicated even for the time. You could have your tunes for a low price. That's how this format took off, folks.
Before we dive into the 8-Track format in more detail, let's get this deck apart, shall we? We'll need a 1/4" nut driver to get into this one. Blue screws indicate two of the bottom cover screws... the 8-Track module is bolted to this cover inside. Orange arrows show you two of the screws holding the front face on.
Look what we have here (above), indicated by the red arrow. A damaged wire. In fact, this is the illumination wire. If I were refurbishing this deck, I would have to address this with some heatshrink tubing.
The back panel. Blue again indicates the bottom cover screws, while red shows you the top cover screws. We'll leave the remaining brass colored screws alone - they do not need to be removed to service this deck.
Note the presence of the smaller metal screws with the slotted heads near the blue arrowed screws - these help to hold the 8-Track module to the bottom panel. We'll get to those later.
Here's the connector shot for this deck. Too old to get the black and gray connectors Chrysler decks of the eighties, this deck is much easier to figure out. The white connector is the speaker output harness. One ground wire, four positive wires. This is a common ground deck, as many Chrysler decks were up until about 1984.
Of the two remaining connectors, the big black one with the red wire is the 12 volt power to the deck, while the orange one is, again, for the illumination.
The other side of the deck. Blue for the bottom cover, red for the face
This is the top of the deck. There's only one item of note here, arrowed in blue. This is the illumination lamp holder, and it is held in by the snap arrowed in red. It's just like the snaps on your winter jacket. To replace the single illumination lamp, you must release the tabs on the side holding the orange wire to the case, undo the snap, and pull the lamp holder straight up and out. It couldn't be much easier.
The bottom cover. All three bronze screws you see here hold the bottom cover to the face.
In all, there are nine screws holding that bottom cover on. We're going to take them all out now and have a look inside the deck for the first time.
The deck folds open like this, so that you can detach the 8-Track module connector, arrowed in blue. It's friction fit, so all you need to do is pull the two halves of the connector apart.
This is what the 8-Track module itself looks like. Most operate pretty much the same way. The cartridge slides in and pushes on the lever arrowed in black. This tells the mechanism to turn on. Since the tape cartridges themselves have the pinch roller, we don't have to worry about one of those here today. This was, in fact, one of the ways they saved money on this format. Because the cartridge has the pinch roller, there is no need to add a mechanism to move one or two into place, as we see with cassettes. (Editor's note: this no doubt added cost to the cartridges, but since those were made by different companies and the cost was passed to the end user, it presumably was still considered a savings.)
You're probably wondering what the other arrows are. Orange is the capstan, which is frequently an issue in 8-Track decks. They wear down with heavy use. (Editor's note: they also tend to get covered in media from the tapes, which makes them sticky; that can be removed with alcohol and a cotton swab.)
The red arrow is a special set of electrical contacts. You see, because the 8-Track tape is one continuous loop with eight tracks, arranged on top of each other (leading to four stereo "programs" on each tape), they had to provide a way to tell the deck when to switch to the next set of tracks by moving the head up or down. This was done by splicing the continuous loop together via a metallic strip. When that strip met the red arrowed contacts, the deck fired that big solenoid on the top right, causing a loud "click," and the tape head moved up or down to the next set of tracks. (With auto-reversing cassettes, the head also moved up or down to get from one set of tracks to the other.)
This was, in fact, the cheap way to do it. More expensive 8-track machines sometimes had a head that could read all tracks at once, and did not require moving, but as yet I have not seen one built like that. This is probably because that anyone who would have been interested in such an improved 8-track deck was likely already enjoying open reel tape technology at home, which is by leaps and bounds superior to all other audio tape formats save for perhaps DAT (digital audio tape) or DCC (digital compact cassette). Pay extra to make the 8-track format sound only a little bit better but still worse than open reel? Most people likely preferred the affordability of the moving head mechanism. They had their turntable and expensive open reel machine at home, if they wanted sound quality.
And really, affordability is what brought the 8-Track to the dance. You couldn't rewind them, due to the way the continuous loop tape is wound. You could barely fast forward them. Only a few decks could ever record to them. The 8-track really was a "well, it's better than humming to myself while drumming on the dashboard" option. Records didn't work as a portable format, though Chrysler tried them for a while. Ditto for open reel tapes, though many companies tried to make them portable. The cassette was mediocre and expensive. What else were you going to do for music on the go back then?
Let's move on, and remove the mechanism from the bottom cover via the blue arrowed screws.
Now we can access the drive belt for the mechanism, and this one has seen better days for sure. On cycling it by hand, I can see a clearly deformed spot in the belt, and the rubber has gone hard. This belt would not last long were I to actually use this deck.
Be careful when you remove the belt on this deck - the flywheel on the right, which drives the capstan, is just sitting in there. It and the capstan will fall out if you're not careful and turn the mechanism over without the belt in place.
In fact, I'll even remove it for you, to show you the wear on the capstan. This deck has played more than a few 8-Track tapes.
The section of the bottom cover where the flywheel rides has a special greased bushing where the shaft sits. If you are refurbishing one of these, make sure you clean up the old grease and apply some new white lithium grease. This deck is more than thirty years old, and so is the grease.
Now, we'll have a look at the rest of the deck, which is refreshingly uncomplicated compared to many of the newer units.
This is what you see when you pull the top cover off, and the insulator found below it. Now, you can inspect the solder joints.
Removing the front face is a little tricky, but we'll do it. Remember those four rusty clips I showed you in the first picture? Pop those out now, and pull the front panel off like so.
The red arrow indicates the illumination lamp bracket. Let me pull that out and I'll show you that now.
The single illumination bulb in this deck is a simple 12 volt bayonet base affair with a blue filter sock over it.
To get the front face housing off, there are a few things to do. First, there are two black plastic bezels over and beneath the tuner indicator to remove. Those are just clipped on. Remove them carefully, so that you don't bend the tuner indicator.
Then, remove the three screws arrowed in blue and pull the entire gray housing forward.
This is a view from behind. Before the front face will come off, you need to unplug the connector arrowed in yellow. Remember which way it goes on. Blue arrows show you the catches for those black plastic tuner bezel pieces - if you're having trouble getting those unsnapped, press against them from this side.
Now... you need to move the tuner indicator so it doesn't catch on the face assembly. Use the tuning knob to move the pointer in the direction indicated by the long red arrow. Move it all the way over, until it lines up with the slot represented by the short red arrow. You can then pull the face off.
Note that the balance control will still be wired up, but those wires should give you enough room to pull the face off.
There... the face is off and we can get into the insides a little easier.
If you are restoring one of these decks, I'll give you a few tips. First, replace all the electrolytic capacitors... in this deck, the ones in the black cans. Replace every last one. Capacitors have a finite life span, and these are almost as old as I am. It is very common for these to have failed by now.
Also clean the potentiometers (the parts that do the work of the knobs) on the top right with some electrical contact cleaner and lube. You can get some at Radio Shack, or your nearest electronics supply store. The one on the very end toward the top middle of the picture is actually the rotary power switch for the unit, which doubles as the switch used to change tape programs, when you push down on the volume control. You likely won't have to do any cleaning there, unless functionality is intermittent. Just make sure you get the four directly in front of it - those are the volume and tone controls. Clean the balance control on the face while you're at it.
Red arrows indicate the two amplifier chips for this deck. You will likely not find replacements for these anywhere, but they are Hitachi 7280s just in case.
Finally, here's the tuner and preset mechanism. This operates like most other mechanical tuners of the day... pull the knob out, dial up your desired station, then push the knob in to hold the preset.
This concludes my look at what is now the oldest car stereo in my collection. I hope you've enjoyed this look into the past as much as I have, though I confess that when cassettes exploded in the eighties my last thought for the 8-Track format was "good riddance." I couldn't wait to be rid of them. But those really were the good old days, weren't they?
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