Hi Alexandre,

A simple way to ensure that you've set things up correctly is to simply place a recording electrode and measure stimulus artifacts with your stimulating electrode immersed in the bath - it seems you do have one showing in the example image you uploaded. Use your stimulus isolator to dial the output all the way down, and stimulus artifact should disappear, and then dial it up gradually, and the amplitude of the stimulus artifact should increase.

In regards to switching between constant current output vs voltage output, the only way I'm aware of is if your stimulus isolator unit itself has the ability to be switched between those two modes.

I'm not aware of any resources to help one set up an instrument/software apart from the manuals that come with the hardware and software, which are available from their website (in case you can't find one in your lab). But, you shouldn't hesitate to call Molecular Device's technical support; I've had a couple of colleagues get in touch with them previously and they both relayed to me that they were thoroughly happy with the support they received from their technical support representatives.

Best of luck,

Haider

Thanks a lot Haider!

I´ll contact Molecular Devices.

Actually I have several questions regarding the use of pClamp software... is a great challenge.

I pretty sure my stimulator is not working. I just carried out somes tests in a hippocampus slice and got no different responses changing the stimulus parameters (ranging from 100 uA to 10 mA). Further, I have many noise issues that must be solved besides dealing with the software.

Anyway, thanks a bunch for your help.

Hi Alexandre

Re the A365 WPI stimulator, it sounds silly to ask but have you checked the battery bank? It uses 16 (I think) 9 volt batteries and it is important to change all of them to new batteries of the same type and make sure it is switched off between sessions. It is a constant current stimulator but can be used in constant voltage mode if you place q load resistor across the terminals and take the output from over the resistor. Also, you can check its output in a similar way by using an oscilloscope across a load resistor and measuring the potential, and then use Ohms law.

The attached file is a screen shot of page 9 of the manual (available for free at: https://www.wpiinc.com/clientuploads/pdf/A365_IMs.pdf)  which talks about both of these things.

Good luck!

John Reynolds 

Hi Alexandre, I agree with John about that you probably have to check the battery bank of your stimulator, but also maybe you could try to borrow another stimulator before and try it to be sure that your pClamp stimulus command are delivered correctly and that you really are changing the intensity output.

I´m not an expert in the use of pClamp but when I have problems sometimes I just check the manuals.

I will attach the manual and a pClamp workshop materias hoping that will be usefull for you.

Greetings

Many thanks John and Alexandra.

Actually, there is a battery charger attached to my stimulator (A365R WPI). In this sense, I believe that the batteries are not the problem.

Further, in a chat with an expert electrophysiologist, he told me that many colleagues of him use "constant current" stim box (and not voltage stimulus). So, the stimulus kind seems to be also not the problem.

I just talked with the thecnician from Molecular Devices. He is going to access my computer and check pClamp configuration and digital output functioning. In fact, the support from Molecular Devices is very friendly and effective.

I´ll let you know if the problem was solved.

Again, thanks a lot for your help.

Regards,

Problem solved.

The main problem was located in the BNC cable which was disrupted.

Thanks everybody for your help.

Further, Molecular Devices support is REALLY KIND AND EFFECTIVE!

Could anyone suggest appropriate BNC cable specification? I´m affraid the coaxial cables I´m using are not good enough to avoid noise.

Hi Alexandre Ademar Hoeller,

can you please share with me the protocol for recording the field?

I'm facing a problem with the program and I'm not sure if it's the protocol.

for instance, is the protocol in the picture you've attached previously is the protocol you're following?

Hi.. we use Axon 700B amplifier and Digidata 1550B digitizer. Pclamp10 dongle is missing is anyone can help?