I have an Audio Research CDT1 (https://www.arcdb.ws/model/CD1). It has occasional errors reading disks, and skips on disks that work fine in other players. I decided to replace the laser, and ordered one from Some Guy On eBay(TM). The replacement went smoothly enough, but on test the player always reports "no disk". The CD doesn't even spin up, the laser mechanism moves the head up and down a few times, then gives up.
I had this issue on a Rega CD player I replaced lasers on, but it was just that I hadn't cleared the ESD protection solder blob. I can't spot a similar blob on this unit.
I've emailed the seller to ask for advice. In the mean time, I wondered if you fine folks might have any suggestions I hadn't thought of. The spinner motor is not being sent power from the board, I checked with a meter, so it's not that the motor failed. I haven't tried reinstalling the old laser, because it's kind of a pain in the ***. I have contacted Audio Research about getting a proper laser, which they have, but apparently they are so behind on orders they can't take my money yet. So, that is on hold.
I had this issue on a Rega CD player I replaced lasers on, but it was just that I hadn't cleared the ESD protection solder blob. I can't spot a similar blob on this unit.
I've emailed the seller to ask for advice. In the mean time, I wondered if you fine folks might have any suggestions I hadn't thought of. The spinner motor is not being sent power from the board, I checked with a meter, so it's not that the motor failed. I haven't tried reinstalling the old laser, because it's kind of a pain in the ***. I have contacted Audio Research about getting a proper laser, which they have, but apparently they are so behind on orders they can't take my money yet. So, that is on hold.
ebay parts is **** and miss.
otherwise check all connections etc that were touched for the change over.
still no good.
swap back the old one.
works now.
get a new one from AR.
Maybe a second as a spare if these are known to wear out.
otherwise check all connections etc that were touched for the change over.
still no good.
swap back the old one.
works now.
get a new one from AR.
Maybe a second as a spare if these are known to wear out.
I reverted back to the old laser. It registered that a disk is present, and spins it up, but then gives "err". Which is somewhat it keeping with its old behavior.
With the new laser, it never even spins the CD up. Which is what lead me to wonder if there was some simple problem, like an ESD blob.
With the new laser, it never even spins the CD up. Which is what lead me to wonder if there was some simple problem, like an ESD blob.
I think that it was Maxell that sold a lens cleaning disc back in the day. Weird looking CD but it was worth keeping around.
I received a new module from Audio Research and installed it. However, the behavior is identical to the eBay replacement. This behavior is identical to that of a Rega unit I repaired, before I realized there was an ESD-protection solder blob that needed to be cleared. However, I do not see any such blob on this Audio Research part, and the eBay seller stated there was no such protection. I have emailed Audio Research for further clarification. In the mean time, I'm hopeful someone on here can point me in a useful direction.
Like the recapping pandemic, if a cd player stops working it just HAS to be the laser assembly.
I'm guessing no other fault finding / diagnoses was performed ?
Problem with any digital device is understanding and then diagnosing them.
IF you even have the gear to do the needed tests and measurements.
NB. For transparency, I readily admit I have also resorted to 'shotgun' repairs with little testing before hand.
I have a dead headphone amp here at present that I'm doing that to by just wholesale replacing the output transistors 🙂
I'm guessing no other fault finding / diagnoses was performed ?
Problem with any digital device is understanding and then diagnosing them.
IF you even have the gear to do the needed tests and measurements.
NB. For transparency, I readily admit I have also resorted to 'shotgun' repairs with little testing before hand.
I have a dead headphone amp here at present that I'm doing that to by just wholesale replacing the output transistors 🙂
All evidence pointed to the laser. The original behavior was that it would read some disks, some of the time. Now it reads no disks at all. At minimum, there is something wrong with the new laser or installation, because the behavior is worse than before, and nothing else has changed.
I'll throw this out, no idea if it is really a possibility. The new laser may load the driver circuit in a way that causes complete failure instead of the previous sometimes fail. Maybe measure the laser voltage with a scope with the old/new. I've never messed with this so I could be totally off here.
Put the original laser back in place, see if the behavior changes.
if it doesn't change, look at the two TCA0372dp2s as well as the TDA1301.
It still looks a lot like a Philips diagram, so there should be a favorable outcome.
if it doesn't change, look at the two TCA0372dp2s as well as the TDA1301.
It still looks a lot like a Philips diagram, so there should be a favorable outcome.
Looking at the image on the website link, the digital section with the large ground plane looks typically Philips. It is interesting that ARC's power supply section seems to be on the same large circuit board, so it is entirely possible that there was some sort of deal done between ARC and Philips back in the day.
It is worth checking the power supply voltages when different laser heads are installed. (do you have a meter?)
It is worth checking the power supply voltages when different laser heads are installed. (do you have a meter?)
I did some cross-searching to try to find a common PCB and found nothing.
It looks like a Philips architecture re-routed by AR on a new pcb but the base of the drive is clearly philips.
Hi,
one of my colleagues has a similar problem with the same cd player:
The laser has been replaced by this one:
https://it.aliexpress.com/item/1005005476714404.html
But when the cd is loaded, an ERROR message appears on the display, and it doesn't work.
Can someone point me to some threads that explain how to repair it?
What instrumentation do I need?
one of my colleagues has a similar problem with the same cd player:
The laser has been replaced by this one:
https://it.aliexpress.com/item/1005005476714404.html
But when the cd is loaded, an ERROR message appears on the display, and it doesn't work.
Can someone point me to some threads that explain how to repair it?
What instrumentation do I need?
In my case, the problem ended up being that the replacement mechanism had little "clips" that required you to push the CD onto (like a laptop CD drive), while the original didn't; the CD simply dropped into place. I took the new laser mechanism and swapped it onto the old CD mount, and everything worked great.
In your case, I would throw that Ali Express laser in the trash and order the correct part from Audio Research. It's only $75 or so.
Copied from my email:
"Thank you for choosing Audio Research. Yes, we have the laser module for the CD1 in stock. Part number is 66000231. Cost is $75 plus shipping. If you would like to order, please send me your address and phone number. Thank you"
In your case, I would throw that Ali Express laser in the trash and order the correct part from Audio Research. It's only $75 or so.
Copied from my email:
"Thank you for choosing Audio Research. Yes, we have the laser module for the CD1 in stock. Part number is 66000231. Cost is $75 plus shipping. If you would like to order, please send me your address and phone number. Thank you"
When do you have got that reply?
My colleague got a "it's a 25 plus years old item, we do not service it anymore".
My colleague got a "it's a 25 plus years old item, we do not service it anymore".
I sent an email to service@audioresearch.com on 8/14/2024:
"I am writing to inquire about pricing and availability of a replacement laser module for a CDT-1 transport. I do not require service, just the part."
I received the reply I quoted above. I would contact them at that email address and ask to place an order for part number 66000231.
Perhaps they thought your colleague wanted to send the unit in for them to service, and they were saying they dont work on older units anymore? I've never had a problem getting 40 year old parts from them, as long as they haven't run out.
"I am writing to inquire about pricing and availability of a replacement laser module for a CDT-1 transport. I do not require service, just the part."
I received the reply I quoted above. I would contact them at that email address and ask to place an order for part number 66000231.
Perhaps they thought your colleague wanted to send the unit in for them to service, and they were saying they dont work on older units anymore? I've never had a problem getting 40 year old parts from them, as long as they haven't run out.