Rivem
0
- Joined
- Feb 16, 2016
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EDIT: Success! Wasn't really planning to get a laser power meter any time soon, but the project seemed intriguing and was a good deal. It panned out, and now I've saved a lot on an LPM that should suit my needs well. 
For the details on the repair, there were three problems I had to fix:
1. Wouldn't connect to a computer.
For this problem, I popped the device open and immediately saw the terrible USB cable. The conductors were unusually thin and very brittle. Cables like this easily break due to odd angles and movement. I confirmed with a continuity test with my multimeter. The only reasonable solution is a replacement. Cutting an old cable and soldering it onto the USB contacts did the trick, but I'd advise carefully making sure you solder things in where they're supposed to go. The original conductor colors weren't the standard, but they were close enough to guess. I've left mine in a temporary state so that I can eventually put in a female USB mini connector.
2. Connected to a computer but driver failed in Windows 10
This problem has been fairly common recently, and I figured it would be the case when I saw the generic USB to serial board. The issue is that Windows 8 and onward marked a change from drivers being mostly managed by the users and PC OEMs to being almost entirely managed by Microsoft automatically. This made using most peripherals a lot easier since drivers don't have to be manually installed any more, but it also allowed manufacturers to push whatever drivers they wanted onto consumers. USB to serial controllers had serious issues due to the companies FTDI and Prolific making drivers that wouldn't work with (destroy in FTDI's case) the fairly common counterfeit chipsets found in many peripherals with Chinese manufacturing origins.
Anyway, the fix isn't too bad. Just search around for information on counterfeit compatible Prolific PL2303 drivers, and manually install one. They'll be an older driver from before the anti-counterfeit features. Install it, find the device in your device manager, and update the driver to the older one. Be careful not to get yourself a virus though. FYI, the PC might revert to using the newer driver if you connect to a different USB port.
3.Noisy readings without zeroing or any clear curves
This issue was a little confusing at first, but I discovered there were serious jumps if I moved the TEC sensor around. I figured it was the cable considering how the USB was, and sure enough, there was way too much resistance and loss of continuity depending upon the position. I fixed this one using the original connector on some spare RJ-174 Coax cable which barely fit the old connector just perfectly. It's a lot beefier and less resistant than the original cable, but the numbers don't seem too far off. That stabilized the numbers and gave good zeroing.
Photos:
The LPM electronics are on the left with the TEC cable coming out, and the counterfeit USB-Serial controller is on the right with the tentative USB setup until I can order my connectors.
The bump is from my inability to see the laser dot through my safety goggles and trying to take a picture.
Original*****************************************************
I bought a broken 2.5w Laserbee that wouldn't connect to a computer from JLM. It was a good deal, so I figured I'd give it a shot.
Right out the box, I noticed the USB cable was absolutely terrible. Worst Chinese cable I've seen in a while. I broke out the continuity tester, and sure enough, it's broken on 3 out of 4 conductors. As a test, I could easily split the conductors with a pinch.
There were some really bad solder joints on the boards I ignored, but they looked functional enough. I didn't want to risk it without my good gear.
I cut an older, unused donor cable and soldered it in. Connection to the Prolific USB-Serial device was immediately successful.
I've read about how these don't work with Windows 8 and 10 drivers, and I'm interested to see how I can get around it for myself. Still working on it at the moment since I can't quite get Peregrine to even start on my laptop yet. I also can't decide if I should replace the hardware or just work around the driver. Stay tuned for updates and photos.
Edit: Got it working and connected to Peregrine.
There's an issue in the TEC cable as well though. Readings are all over and noisy. I'm thinking it's the solder joint between the tec leads and cable.
Edit 2: Another very poor quality cable. There's high resistance on both conductors, and continuity is lost with bending. I'll have to replace it, but I think I've got some that'll suit it just fine. That's a project for tomorrow.
Edit 3: Just found a little bit of spare RJ174 and soldered it up as a replacement TEC cable. Have to run some errands, but I'll test it tonight.
************************************************************
For the details on the repair, there were three problems I had to fix:
1. Wouldn't connect to a computer.
For this problem, I popped the device open and immediately saw the terrible USB cable. The conductors were unusually thin and very brittle. Cables like this easily break due to odd angles and movement. I confirmed with a continuity test with my multimeter. The only reasonable solution is a replacement. Cutting an old cable and soldering it onto the USB contacts did the trick, but I'd advise carefully making sure you solder things in where they're supposed to go. The original conductor colors weren't the standard, but they were close enough to guess. I've left mine in a temporary state so that I can eventually put in a female USB mini connector.
2. Connected to a computer but driver failed in Windows 10
This problem has been fairly common recently, and I figured it would be the case when I saw the generic USB to serial board. The issue is that Windows 8 and onward marked a change from drivers being mostly managed by the users and PC OEMs to being almost entirely managed by Microsoft automatically. This made using most peripherals a lot easier since drivers don't have to be manually installed any more, but it also allowed manufacturers to push whatever drivers they wanted onto consumers. USB to serial controllers had serious issues due to the companies FTDI and Prolific making drivers that wouldn't work with (destroy in FTDI's case) the fairly common counterfeit chipsets found in many peripherals with Chinese manufacturing origins.
Anyway, the fix isn't too bad. Just search around for information on counterfeit compatible Prolific PL2303 drivers, and manually install one. They'll be an older driver from before the anti-counterfeit features. Install it, find the device in your device manager, and update the driver to the older one. Be careful not to get yourself a virus though. FYI, the PC might revert to using the newer driver if you connect to a different USB port.
3.Noisy readings without zeroing or any clear curves
This issue was a little confusing at first, but I discovered there were serious jumps if I moved the TEC sensor around. I figured it was the cable considering how the USB was, and sure enough, there was way too much resistance and loss of continuity depending upon the position. I fixed this one using the original connector on some spare RJ-174 Coax cable which barely fit the old connector just perfectly. It's a lot beefier and less resistant than the original cable, but the numbers don't seem too far off. That stabilized the numbers and gave good zeroing.
Photos:
The LPM electronics are on the left with the TEC cable coming out, and the counterfeit USB-Serial controller is on the right with the tentative USB setup until I can order my connectors.
The bump is from my inability to see the laser dot through my safety goggles and trying to take a picture.
Original*****************************************************
I bought a broken 2.5w Laserbee that wouldn't connect to a computer from JLM. It was a good deal, so I figured I'd give it a shot.
Right out the box, I noticed the USB cable was absolutely terrible. Worst Chinese cable I've seen in a while. I broke out the continuity tester, and sure enough, it's broken on 3 out of 4 conductors. As a test, I could easily split the conductors with a pinch.
There were some really bad solder joints on the boards I ignored, but they looked functional enough. I didn't want to risk it without my good gear.
I cut an older, unused donor cable and soldered it in. Connection to the Prolific USB-Serial device was immediately successful.
I've read about how these don't work with Windows 8 and 10 drivers, and I'm interested to see how I can get around it for myself. Still working on it at the moment since I can't quite get Peregrine to even start on my laptop yet. I also can't decide if I should replace the hardware or just work around the driver. Stay tuned for updates and photos.
Edit: Got it working and connected to Peregrine.
There's an issue in the TEC cable as well though. Readings are all over and noisy. I'm thinking it's the solder joint between the tec leads and cable.
Edit 2: Another very poor quality cable. There's high resistance on both conductors, and continuity is lost with bending. I'll have to replace it, but I think I've got some that'll suit it just fine. That's a project for tomorrow.
Edit 3: Just found a little bit of spare RJ174 and soldered it up as a replacement TEC cable. Have to run some errands, but I'll test it tonight.
************************************************************
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