Hey Folks!
I'm hoping you experts can help me out.
I own a couple vintage Kenwood DP-3300d and a couple Kenwood DP-1100d Cd players.
One DP-3300d and one DP-1100d are in virtually mint condition and the other 2 are spares that I aquired over the last few years as I love that old stuff.
One of the DP-1100d's I aquired from Germany that was still new in the box with all packaging and intact and it's the only one of the bunch that will play CD-R's properly and I'm guessing that it's because the laser optics has little mileage on it.
I changed the cord and hooked it up to the 120 tap on the transformer and am in the process of recapping it as well as the DP-3300d. I also have a brand new laser pick-up that I was able to get from Kenwood that will be going into the 3300.
Both units are exactly the same with the exception of the 3300 having the extra digital fiber optic output and a couple extra buttons on the face plate, even both transports are the same and interchangeable.
I also have a Sper portable laser optic meter on its way to me so that I can verify the output of the laser diodes and see if they fall withing specs.
My plan is to experiment with one of the spare units and mark the adjustment pots with a fine tip marker, check the laser output, hook up my test equipment and scope and see if everything is within specs and practice with this unit. I'm no expert at this and it would be a great learning experience for me.
Looking over the service manuals for these units, the 1100 requires a Type 3 test disc and the 3300 requires the Type 4 test disc to do the tracking, focus and alignment adjustments. I contacted Kenwood Japan to get info on these discs, and they informed me that they are Sony YEDS 7 type 3 and Sony YEDS 18 type 4 cd's. The service manual does not indicate any specific track that needs to be played.........it just simply ask to insert the disc into the tray and complete loading then follow the rest of the procedure outlined in the manual.
My question is, if there is no specific track required and these cd's are no longer available, is there a substitute Cd that I can use that will work?
Any help would be greatly appreciated! 🙂
Roland
I'm hoping you experts can help me out.
I own a couple vintage Kenwood DP-3300d and a couple Kenwood DP-1100d Cd players.
One DP-3300d and one DP-1100d are in virtually mint condition and the other 2 are spares that I aquired over the last few years as I love that old stuff.
One of the DP-1100d's I aquired from Germany that was still new in the box with all packaging and intact and it's the only one of the bunch that will play CD-R's properly and I'm guessing that it's because the laser optics has little mileage on it.
I changed the cord and hooked it up to the 120 tap on the transformer and am in the process of recapping it as well as the DP-3300d. I also have a brand new laser pick-up that I was able to get from Kenwood that will be going into the 3300.
Both units are exactly the same with the exception of the 3300 having the extra digital fiber optic output and a couple extra buttons on the face plate, even both transports are the same and interchangeable.
I also have a Sper portable laser optic meter on its way to me so that I can verify the output of the laser diodes and see if they fall withing specs.
My plan is to experiment with one of the spare units and mark the adjustment pots with a fine tip marker, check the laser output, hook up my test equipment and scope and see if everything is within specs and practice with this unit. I'm no expert at this and it would be a great learning experience for me.
Looking over the service manuals for these units, the 1100 requires a Type 3 test disc and the 3300 requires the Type 4 test disc to do the tracking, focus and alignment adjustments. I contacted Kenwood Japan to get info on these discs, and they informed me that they are Sony YEDS 7 type 3 and Sony YEDS 18 type 4 cd's. The service manual does not indicate any specific track that needs to be played.........it just simply ask to insert the disc into the tray and complete loading then follow the rest of the procedure outlined in the manual.
My question is, if there is no specific track required and these cd's are no longer available, is there a substitute Cd that I can use that will work?
Any help would be greatly appreciated! 🙂
Roland
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I have an YEDS18 CD, (will not sell it) but you´ll never need it anyway-any good CD will do.
Those YEDS-CD´s "only" garuanteed for errorless manufacturing.
Use any of your discs whioch is in good shape, try to do the adjustment half way into the disc.
No need to touch the laser power, yóu´ll only screw things up.
I have a Toshiba XR-Z70 which is very similöar of the Kenwood DP1100.
Even though they are second generation from 1984, tracking with CD´Rs is superb, better than many players from the mid eighties.
Those YEDS-CD´s "only" garuanteed for errorless manufacturing.
Use any of your discs whioch is in good shape, try to do the adjustment half way into the disc.
No need to touch the laser power, yóu´ll only screw things up.
I have a Toshiba XR-Z70 which is very similöar of the Kenwood DP1100.
Even though they are second generation from 1984, tracking with CD´Rs is superb, better than many players from the mid eighties.
Thanks for the response!
So what your saying it's not any specific track on the Sony cd but the quality of manufacturing?
I currently have this cd....
Audio Test CD Reference Tones AND Sweeps Disc Lasertrak CD2000 | eBay
And this one.....
CA Audio Equipment SET UP Test Tones CD | eBay
Would any of these be considered quality or just cheap junk?
Also, I have an old Telarc cd California project papa doo run run that is suppose to be of high quality. Would that be a good cd to use?
So what your saying it's not any specific track on the Sony cd but the quality of manufacturing?
I currently have this cd....
Audio Test CD Reference Tones AND Sweeps Disc Lasertrak CD2000 | eBay
And this one.....
CA Audio Equipment SET UP Test Tones CD | eBay
Would any of these be considered quality or just cheap junk?
Also, I have an old Telarc cd California project papa doo run run that is suppose to be of high quality. Would that be a good cd to use?
Ooops! I forgot to ask what you mean by second generation cd player?
How many generations is there and what's the difference?
How many generations is there and what's the difference?
I also just discovered this cd......
Digital Recordings - Advanced Research and Development in Acoustics
It's the cd-check one in the list
Any opinions?
Digital Recordings - Advanced Research and Development in Acoustics
It's the cd-check one in the list
Any opinions?
I habe Digital recordings also - nice to find out how good error correction is
but not very usable for alignment. Again, any scratchless CD will do the job.
A very good book to learn about CD-Players, especially the first generations and to answer all of your questions:
Understanding and Servicing CD Players
by Ken Clements
Beneath a link to the offers
http://www.amazon.com/gp/offer-listing/0750609346/ref=rdr_ext_uan
but not very usable for alignment. Again, any scratchless CD will do the job.
A very good book to learn about CD-Players, especially the first generations and to answer all of your questions:
Understanding and Servicing CD Players
by Ken Clements
Beneath a link to the offers
http://www.amazon.com/gp/offer-listing/0750609346/ref=rdr_ext_uan
I own a Kenwood DP-3300d
I purchased used (close to new) for $250 about 14 years a go.
Nice player1
Greetings
I purchased used (close to new) for $250 about 14 years a go.
Nice player1
Greetings
Thanks for that!
I do own a couple books about servicing cd players that I'm going to have to dig out!
As far as adjusting the laser output, the service manual does not indicate any adjustment. It just says to verify that the output falls within a certain range. The only place that I can find a pot to adjust is on a small board that's part of the laser pickup. Once I get my laser output meter, I will check the output of all 4 units that I have.
I just snapped up a Sony YEDS-18 Type 4 test Cd on e-bay.
Hopefully its in as good a condition as the seller proclaims!
Hopefully its in as good a condition as the seller proclaims!
+1
this is a good book on basics and repair.
i even think i got mine from amazon also.
🙂
mlloyd1
this is a good book on basics and repair.
i even think i got mine from amazon also.
🙂
mlloyd1
...
A very good book to learn about CD-Players, especially the first generations and to answer all of your questions:
Understanding and Servicing CD Players
by Ken Clements
Beneath a link to the offers
Amazon.com: Buying Choices: Understanding and Servicing CD Players
I have a book on compact disc player repair and troubleshooting by Homer L Davidson that I've had for over 20 years that is also a great book. I am going to read over the chapter on alignments as he goes into lots of detail.
What you are looking for in a good test disc is one of good reflectivity. As you have a scope you should look at the signal level from a few different discs where you should find all nominally the same with perhaps an odd one out that has low output (which would not make a good test disc).
This thread might help you with adjustments. There are a couple of short video files attached to the end of post #1 (I don't do YouTube 😉) showing one of the more tricky adjustments and a practical way to do it.
http://www.diyaudio.com/forums/digital-source/226288-sony-cdp790-kss240-restoration-project.html
This thread might help you with adjustments. There are a couple of short video files attached to the end of post #1 (I don't do YouTube 😉) showing one of the more tricky adjustments and a practical way to do it.
http://www.diyaudio.com/forums/digital-source/226288-sony-cdp790-kss240-restoration-project.html
Thanks Mooly!
I can practice all of this on my spare unit and verify with my scope that everything is ok.
I received my laser output meter yesterday and tried to check the output of the laser in my spare unit but am not having much luck although I did not spend much time on it yet.
I followed the service manual setup but I must be doing something wrong. It says to ground testpoint seven and open the tray then place laser output meter onto laser to read output which I did.... no reading! Then I realized that the unit needs to be in setup mode and tried that...still nothing. But yet I know the pickup works cause I can play a Cd. I must be doing something wrong and will have to read more. The laser meter that I purchased is a Sper Pocket Laser Power Meter - 840011 and will read over a range of 400-1100nm so it should work. I did test the meter with a laser pointer and it works fine so it's obviously something I'm doing wrong.
I did finish recapping my good unit and it works great! Changed the tray opening belt and greased the gears and gear rack with a slight amount of white lithium grease.....i hope this grease will not harm the plastic gears!!! The package says it is for metal on metal and metal on plastic so I assume it will do the trick.
My Sony yesd-18 type 4 cd that I snagged on e-bay is on its way and should be here this week.
What a great learning experience this is!!!
Roland
I can practice all of this on my spare unit and verify with my scope that everything is ok.
I received my laser output meter yesterday and tried to check the output of the laser in my spare unit but am not having much luck although I did not spend much time on it yet.
I followed the service manual setup but I must be doing something wrong. It says to ground testpoint seven and open the tray then place laser output meter onto laser to read output which I did.... no reading! Then I realized that the unit needs to be in setup mode and tried that...still nothing. But yet I know the pickup works cause I can play a Cd. I must be doing something wrong and will have to read more. The laser meter that I purchased is a Sper Pocket Laser Power Meter - 840011 and will read over a range of 400-1100nm so it should work. I did test the meter with a laser pointer and it works fine so it's obviously something I'm doing wrong.
I did finish recapping my good unit and it works great! Changed the tray opening belt and greased the gears and gear rack with a slight amount of white lithium grease.....i hope this grease will not harm the plastic gears!!! The package says it is for metal on metal and metal on plastic so I assume it will do the trick.
My Sony yesd-18 type 4 cd that I snagged on e-bay is on its way and should be here this week.
What a great learning experience this is!!!
Roland
Sound like you are having fun 🙂
I'll be honest and say I've never really got on with laser power meters. We were 'forced' into getting them by Sony in order to secure a 'Fully Approved Service Centre' rating back in the day. They were never really used beyond curiosity value.
Try your meter (as long as access is OK) in the few seconds the lens performs the focus search operation when the tray is closed. Hold it just a few mm above the lens.
The grease sounds OK compatibility wise (metal/plastics).
I'll be honest and say I've never really got on with laser power meters. We were 'forced' into getting them by Sony in order to secure a 'Fully Approved Service Centre' rating back in the day. They were never really used beyond curiosity value.
Try your meter (as long as access is OK) in the few seconds the lens performs the focus search operation when the tray is closed. Hold it just a few mm above the lens.
The grease sounds OK compatibility wise (metal/plastics).
Well I managed to measure the laser output of both my rebuilt DP-1100d and my spare unit using my newly acquired laser output optical meter.
The service manual says the laser output is within specs if it reads between 100 and 200uw. The rebuilt unit measured in at 170 and the spare at 155.
So after that I started to play with the spare unit and verify all the alignment settings as per the service manual using my scope and for the most part everything was ok.
The problem that I'm having now is that in order to check the focus gain and tracking gain, I need a servo adjusting jig. The service manual shows the Kenwood SGA-01 jig being used for this and requires injecting a 700hz signal at 40mv on a particular pin and reading the output at another pin and adjusting VR3 so the output is also 40mv on the focus and injecting 900hz and adjusting VR4 for 40mv as well. The manual says that if the jig is not available then inject 700hz at .4v and use a L.P.F on the output and adjust VR3 for 40mv for the focus and 900hz at .4v and adjust VR4 for an output of 40mv for the tracking.
I assume that an L.P.F is a low pass filter but how do I make one and how do I know that it will give me the accurate results that I need?
I could really use some expert advice on this one!!
The service manual says the laser output is within specs if it reads between 100 and 200uw. The rebuilt unit measured in at 170 and the spare at 155.
So after that I started to play with the spare unit and verify all the alignment settings as per the service manual using my scope and for the most part everything was ok.
The problem that I'm having now is that in order to check the focus gain and tracking gain, I need a servo adjusting jig. The service manual shows the Kenwood SGA-01 jig being used for this and requires injecting a 700hz signal at 40mv on a particular pin and reading the output at another pin and adjusting VR3 so the output is also 40mv on the focus and injecting 900hz and adjusting VR4 for 40mv as well. The manual says that if the jig is not available then inject 700hz at .4v and use a L.P.F on the output and adjust VR3 for 40mv for the focus and 900hz at .4v and adjust VR4 for an output of 40mv for the tracking.
I assume that an L.P.F is a low pass filter but how do I make one and how do I know that it will give me the accurate results that I need?
I could really use some expert advice on this one!!
You don't really need a servo adjusting jig.
Get a fine tipped white or silver or black pen and precisely mark all the trim pot positions carefully.
Then, and only then, you can try sweeping the F/T gain pots and get a feel for the correct working range for each.
Gains a bit too low will cause drop outs, and gains a bit too high will cause the F/T coils to emit harsh audible sound.
F/T coil drive currents can be substantial, can have an audible power supply impact on other stages, so find somewhere in between that plays correctly with less harsh F/T coil sound.
Cut a triangle from across a strip of black insulation tape (19mm x 4mm).
Stick this triangle in about the middle of the play area of any cd with narrow end pointed toward the center.
This makes the best test disc for F/T gain adjustments.
As the lens tracks across wider and wider black tape section, gains can be easily optimised.
You can look at offset test points with an oscilloscope set to low speed so you are viewing a slowly scrolling envelope with DC input coupling.
Dan.
OK, adjustments......
Firstly, if you want to experiment with filters then that's fine but as Max mentioned, you probably don't really need them. There are other ways and means that will give easier to interpret results, and tbh are darned accurate. A LPF filter is nothing more (at its simplest level) than a resistor and cap in series. That series network is connected across the point you wish to measure with the reading taken across the cap. The idea is the filter removes high frequency noise and makes the lower frequency easier to see. As tracking error fundamentals are low frequency then I'd guess at perhaps a 10k and 1uf as a starting point.
How I'd do it...
Focus and tracking gain have a surprisingly wide margin (the range over which the player actually works OK). These adjustments have no effect on the appearance of the RF signal. All they do is optimise the machine to cope optimally with damaged/warped/scratched discs, mechanical shock and so on.
As you have a scope, try coupling it up to the 'tracking error' waveform test point and look at the signal while playing a normal CD. If possible have the scope set to DC coupling and a relatively slow sweep speed. Now turn the tracking gain down slowly and you will see a point where a low frequency component (and it is low) starts to become apparent as it causes the waveform to rise and fall as it modulates it. The correct point for tracking gain is just a touch before that low frequency component appears. Job done 🙂
Focus gain can set by turning the gain up until the pickup starts to become noisy (the focus coils twittering). Back the gain down a fraction from that point. Job done 🙂
Also make sure any other adjustments such as focus bias are done with the correctly with the scope as those adjustments are critical and alter the RF signal.
Edit... the fundamental appears when the gain is lowered, not raised. Post ammended
Firstly, if you want to experiment with filters then that's fine but as Max mentioned, you probably don't really need them. There are other ways and means that will give easier to interpret results, and tbh are darned accurate. A LPF filter is nothing more (at its simplest level) than a resistor and cap in series. That series network is connected across the point you wish to measure with the reading taken across the cap. The idea is the filter removes high frequency noise and makes the lower frequency easier to see. As tracking error fundamentals are low frequency then I'd guess at perhaps a 10k and 1uf as a starting point.
How I'd do it...
Focus and tracking gain have a surprisingly wide margin (the range over which the player actually works OK). These adjustments have no effect on the appearance of the RF signal. All they do is optimise the machine to cope optimally with damaged/warped/scratched discs, mechanical shock and so on.
As you have a scope, try coupling it up to the 'tracking error' waveform test point and look at the signal while playing a normal CD. If possible have the scope set to DC coupling and a relatively slow sweep speed. Now turn the tracking gain down slowly and you will see a point where a low frequency component (and it is low) starts to become apparent as it causes the waveform to rise and fall as it modulates it. The correct point for tracking gain is just a touch before that low frequency component appears. Job done 🙂
Focus gain can set by turning the gain up until the pickup starts to become noisy (the focus coils twittering). Back the gain down a fraction from that point. Job done 🙂
Also make sure any other adjustments such as focus bias are done with the correctly with the scope as those adjustments are critical and alter the RF signal.
Edit... the fundamental appears when the gain is lowered, not raised. Post ammended
Thanks for the info Dan and Karl!
I would love to experiment with both suggestions as this is a learning thing for me! And since I have a spare unit to play with, I might as well go for it!
I had already purchased a fine tip marker to mark the trim pots before adjusting them so they could be returned to their original setpoint which is what I did when I was verifying the alignments.
Karl, you mention how important focus bias is.
The Kenwood service manual list the following adjustments in the same order...
VCO adjustment
RF offset check
Tangential setting
Focusing offset coarse adjustment
T.Error balance coarse adjustment
Tangential and focus offset fine adjustment
T.Error balance fine adjustment
Focus gain adjustment
Tracking gain adjustment
DAC adjustment
Which one of the above is the same as focus bias?
Also, I could make the L.P.F as you mention as I do have the components at home...pretty simple but I'm not sure how this will affect the output measurements if I'm not using the exact same value components that Kenwood used in their L.P.F.
If the values are not the exact same, would my output results across the cap possibly differ with different value components?
I'm not sure if I'm explaining myself correctly on that.
Roland
I would love to experiment with both suggestions as this is a learning thing for me! And since I have a spare unit to play with, I might as well go for it!
I had already purchased a fine tip marker to mark the trim pots before adjusting them so they could be returned to their original setpoint which is what I did when I was verifying the alignments.
Karl, you mention how important focus bias is.
The Kenwood service manual list the following adjustments in the same order...
VCO adjustment
RF offset check
Tangential setting
Focusing offset coarse adjustment
T.Error balance coarse adjustment
Tangential and focus offset fine adjustment
T.Error balance fine adjustment
Focus gain adjustment
Tracking gain adjustment
DAC adjustment
Which one of the above is the same as focus bias?
Also, I could make the L.P.F as you mention as I do have the components at home...pretty simple but I'm not sure how this will affect the output measurements if I'm not using the exact same value components that Kenwood used in their L.P.F.
If the values are not the exact same, would my output results across the cap possibly differ with different value components?
I'm not sure if I'm explaining myself correctly on that.
Roland
Also, I did the RF offset check and the service manual says it is acceptable if around -.7 v.
I could not get a reading on my scope for this whatsoever no matter what setting on my scope I used. Obviously I'm doing something wrong but I wish I could figure it out...
It's not like there is any adjustment for it anyways but still would like to get a reading.
Roland
I could not get a reading on my scope for this whatsoever no matter what setting on my scope I used. Obviously I'm doing something wrong but I wish I could figure it out...
It's not like there is any adjustment for it anyways but still would like to get a reading.
Roland
Some of these adjustments go under different names and its confusing. Some players also have adjustments that others do not.
The one not touch is VCO (voltage controlled oscillator). It won't have changed from new and to adjust correctly you need a frequency counter.
Focus bias could be what they call focus offset. The thing to do is have the scope coupled up to the RF as you adjust it. It will be very obvious because the amplitude of the RF will change and it will become blurred. You are aiming for maximum amplitude and the clearest possible 'diamond' shape in the signal.
For the LPF results to tie in with Kenwood's description you would have to use the exact values they suggest. I was more just generalising on how it worked.
The one not touch is VCO (voltage controlled oscillator). It won't have changed from new and to adjust correctly you need a frequency counter.
Focus bias could be what they call focus offset. The thing to do is have the scope coupled up to the RF as you adjust it. It will be very obvious because the amplitude of the RF will change and it will become blurred. You are aiming for maximum amplitude and the clearest possible 'diamond' shape in the signal.
For the LPF results to tie in with Kenwood's description you would have to use the exact values they suggest. I was more just generalising on how it worked.
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