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Hi Greg,</div>
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That is something that I can help out with.</div>
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>From the specs of the photodiodes and laser, it looks like the maximum current we can expect (if everything is perfect and everything behaves ideally) is ~12 mA when the 442-nm wavelength is used. It also looks like we'll have two photodiodes to measure at
the same time during tests.</div>
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With that, something like a Keithley Model 6482, dual-channel picoammeter could be helpful.
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This picoammeter has a readout range of 1 fA - 20 mA and also has built-in GPIB and RS-232 interfaces for remote control in addition to a local readout screen.</div>
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It's base cost is ~$6,500 according to their website<br>
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Does this fit into what you're looking for in terms of "quick" and "relatively cheap"?<br>
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-Tyler<br>
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<div id="divRplyFwdMsg" dir="ltr"><font face="Calibri, sans-serif" style="font-size:11pt" color="#000000"><b>From:</b> Grzegorz Kalicy <gkalicy@jlab.org><br>
<b>Sent:</b> Monday, September 26, 2022 1:24 PM<br>
<b>To:</b> Tyler Lemon <tlemon@jlab.org><br>
<b>Subject:</b> Readout for the DIRC QA laser lab</font>
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Hi Tyler,</div>
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As I mentioned some time ago I'm trying to avoid unnecessarily complicated readout for photodiodes that we used in original setup in GSI. However, I'm struggling a bit with finding best option (quick, relatively cheap, and useable later for final automatized
setup version). Who in DSG I could reach out for advise?</div>
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Cheers,</div>
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Greg</div>
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