Miniscopes No Longer Connecting - No Blue LED

[Chris Adam]

Hi,

I have been successfully using the V4 miniscopes for a while, but recently, I have been unable to get them to connect with the DAQ box. I stopped running animals for a couple months, and when I went to use the miniscopes again they would no longer connect to the DAQ box (the miniscopes and DAQ box had been sitting safely in a drawer). All three green lights turn on on the miniscope DAQ box (Miniscope DAQ v3.3 from open-ephys), and the red LED on the miniscope also turns on; however the blue LED from the miniscope does not turn on, and the software says the the miniscope cannot connect. I tried 3 different miniscopes (2 I had been using successfully, and 1 brand new one - all from open ephys), and none of them worked. Any ideas of what could have happened?

I'm guessing it may be an issue with the DAQ box, so I ordered a new one, but we are still waiting for it to come in. Is there any other troubleshooting I can do? I recently noticed that one of the miniscopes is getting especially hot when plugged into the DAQ box for a minute or 2 (I have not checked if this is also happening with the other 2 miniscopes). This would make me think it could be a short or some issue with the coax cable; however, I would be surprised if this happened on all 3 miniscopes at the same time. I opened the DAQ box and nothing looked obviously wrong (i.e. nothing looked burnt). Any troubleshooting ideas would be greatly appreciated. Thanks in advance!!

Chris

[zahra rezaei]

Hi Adam,

Are you sure that you are using USB 3 port?

Zahra

[Daniel Aharoni]

Hi Chris,

Below is a list of the usual culprits for this sort of issue:

• A bad USB cable. Many USB3 cables do not meet the actual USB3 specifications and can cause connection issues. 
• Plugging into a USB2 port instead of a USB3 port
• A damaged L13 inductor in the Miniscope DAQ. Search this google group for "L13" and "Inductor" to find out more. But basically a previous short on the coax cable could cause the L13 inductor to burn out and cause all Miniscopes to fail to connect until the L13 connector is replaced. All 3 green status lights sometimes will still look on and the red LED on the Miniscope will also be one. Before trying any other DAQ, verify that these isn't a short across any of your coax cables.
• Bad coax cables or coax cable connectors. This likely isn't the case since you are having issues across all 3 Miniscopes.

[Chris Adam]

Thanks for getting back to me!

Zahra - Yes, I have tried multiple computers always using a USB 3 port and unfortunately still had the same issue.

Daniel - I troubleshot most of these things before posting based on previous issues raised in this forum. In more detail:

• A bad USB cable. Many USB3 cables do not meet the actual USB3 specifications and can cause connection issues.

• • I tired multiple USB cables (2 of which were working previously). I learned this the hard way because the original cable I got with the miniscopes was not good enough and led to these types of issues.

• Plugging into a USB2 port instead of a USB3 port

• • I have definitely been using USB3 ports

• A damaged L13 inductor in the Miniscope DAQ. Search this google group for "L13" and "Inductor" to find out more. But basically a previous short on the coax cable could cause the L13 inductor to burn out and cause all Miniscopes to fail to connect until the L13 connector is replaced. All 3 green status lights sometimes will still look on and the red LED on the Miniscope will also be one. Before trying any other DAQ, verify that these isn't a short across any of your coax cables.

• • I used a multimeter and measured 0-1ohm resistance across the L13 inductor. I also measured a 1ohm resistance when I put one lead on either side of the L13 inductor and the other on SMA connector on the DAQ box that the miniscope connects to (I assume there would be no connection if the L13 inductor was blown?). The inductor itself also looks fine (i.e. not obviously burnt). I can definitely try replacing this if we think it is still the problem. There was also no connection between the ground of the DAQ box SMA connector and the L13 inductor (I checked in case there was a short on the DAQ box end). There is no connection between the signal pin and ground on the coax cable coming from the miniscope itself.

• Bad coax cables or coax cable connectors. This likely isn't the case since you are having issues across all 3 Miniscopes

• • Agreed, especially since they were working previously and a brand new one also had the same issue.

The new DAQ box should arrive in the next day or so. I'll check again to make sure there isn't a short in the coax cable of the miniscope before testing the new DAQ. Still confused to as what happened, but if a new one fixes it I'll be happy!

I'll send an update whether or not the new box works out. Thanks again for the input!!

Chris

[Chris Adam]

Everything works with the new DAQ box! Still not sure what the issues was with the old one since the L13 inductor seemed to be in tact and there were not any shorts in the miniscope coax cables. I may still try replacing the L13 inductor to have the old DAQ box as a backup. I would definitely recommend that people have a backup DAQ box in case they run into an issue like this mid experiment since they're not that expensive

[Daniel Aharoni]

Thanks for the update Chris. This sounds very much like a damaged L13 inductor. Sometime you can clearly see some discoloration around the inductor but not always. Definitely try swapping it out for a new one as this very likely will fix the DAQ.