Re: [AUDITORY] EEG purchase (Amos Boasson )


Subject: Re: [AUDITORY] EEG purchase
From:    Amos Boasson  <agboas@xxxxxxxx>
Date:    Fri, 19 Aug 2022 13:44:31 +0300

--000000000000a4fcbb05e695caf5 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable Hello again, The dithering process is related to the process of assigning a digital value to the analog incoming data. It is an intentionally applied form of noise, used to randomize quantization error. However, here it apparently creates 'spurious tones' due to 'not-fully-damped resonance in the feedback circuit'. On the Fourier graph (when you zoom in quite a lot at high frequencies) it results in extra sharp 'needles', mainly at multiples of eight, but also (less) at multiples of two. The needles do NOT diminish toward higher frequency (they are 'of nearly infinite width'), and therefore disturb more the higher one's 'treasure data' - which do succumb to the 1/f rule - reside. These technical details are abridged from Biosemi's responses to our questions upon encountering the issue. It is not possible to filter this contamination out. In my study the sampling rate was 16384 Hz (Biosemi's Mode 7) with 32+8 electrodes. I was looking (among other things) for brainstem FFR to 530 Hz pure (and stable) tones. Due to presenting the stimulus in alternate polarities (as recommended by the custom practice [but, btw, not by all researchers]), I was looking for the response (in the combined data of the two polarities) at 1060 Hz. This is definitely not a regular region of interest even to FFR researchers, who normally probe speech FFR, at about a quarter of this value; it would disturb them less (but perhaps worth checking anyway). Also, speech FFR would involve gliding frequencies, where you may also still be able to see the beautiful, flexible response. In my case it disturbed more. And, unfortunately, I found it after all the experiments had been conducted=E2=80=A6 As I said, Biosemi seem to be on the verge of launching a new product which does not involve the same technology at all. This has been some time since they said that. Hopefully, this will happen soon. Other than this issue, the data we collected with their equipment is beautiful=E2=80=A6 :) Amos P.S. Alain: Of course we first checked if it is a light bulb or some un-isolated cable etc or a bad electrode. But then Biosemi confirmed the problem resides in the ADC process. =E2=80=AB=D7=91=D7=AA=D7=90=D7=A8=D7=99=D7=9A =D7=99=D7=95=D7=9D =D7=95=D7= =B3, 19 =D7=91=D7=90=D7=95=D7=92=D7=B3 2022 =D7=91-10:05 =D7=9E=D7=90=D7=AA= =E2=80=AAPetter Kallioinen=E2=80=AC=E2=80=8F <=E2=80=AA petter@xxxxxxxx=E2=80=AC=E2=80=8F>:=E2=80=AC > keep in mind that in the Biosemi ActiveTwo system a not-so-widely-known > problem exists, of the signal being contaminated by the dithering process > in the Sigma-Delta ADC box, at frequency-multiples related to the samplin= g > rate. > > > I did not know about this. How high frequencies are we talking about here= ? > Is there a thorough description of the problem somewhere? > > I=E2=80=99m not worried, but it is good to know... > > Thanks, > Petter > > On 18 Aug 2022, at 18:25 , Amos Boasson <agboas@xxxxxxxx> wrote: > > Dear Carlos, and list members: > Carlos, keep in mind that in the Biosemi ActiveTwo system a > not-so-widely-known problem exists, of the signal being contaminated by t= he > dithering process in the Sigma-Delta ADC box, at frequency-multiples > related to the sampling rate. > This problem disturbs mainly if you are interested in spectrum analysis a= t > higher frequencies, as for examples in studies of the Frequency Following > Response (FFR), where presentation of the stimulus in alternate polaritie= s > leads you to look for a response at double the stimulus frequency. Becaus= e > of the 1/f decrement, mechanical 'side-effects' infiltrating the signal, > unremovable, are more and more disturbing. the higher your frequency regi= on > of interest. > Biosemi intends to implement a whole different technology in their next > model (ActiveThree?), which would eliminate this problem, but I have not > seen it on their site yet. > This problem may not disturb some kinds of analysis, but you may want to > consider it. > Good luck with your new lab! > Sincerely, Amos Boasson > > =E2=80=AB=D7=91=D7=AA=D7=90=D7=A8=D7=99=D7=9A =D7=99=D7=95=D7=9D =D7=93= =D7=B3, 17 =D7=91=D7=90=D7=95=D7=92=D7=B3 2022 =D7=91-7:07 =D7=9E=D7=90=D7= =AA =E2=80=AAJan Schnupp=E2=80=AC=E2=80=8F <=E2=80=AA > 000000e042a1ec30-dmarc-request@xxxxxxxx=E2=80=AC=E2=80=8F>:=E2=80= =AC > >> I cannot recommend strongly enough AGAINST the EGI setup. I had inherite= d >> one of their systems. It was terribly buggy. Lost parts of the signal. L= ost >> triggers. My PhD student lost many months trying to debug the device or >> find work-arounds. Their customer service was unresponsive. It was simpl= y >> terrible. What rescued my student was that we were able to get an ANT EE= Go >> system from a friend, which perhaps hasn't the greatest S/N but it was >> quite adequate, and at least it was relatively straight-forward to get t= o >> work as advertised and we got some nice studies done with it. ANT now al= so >> offer a sponge cap for their EEGo system which can reduce prep time. We >> ordered one but we haven't received it yet so I can't tell you whether t= he >> S/N is adequate. >> Under absolutely no circumstances would I ever again waste a single >> dollar or minute of my time on anything EGI. >> >> Best wishes, >> >> Jan >> >> >> --------------------------------------- >> Prof Jan Schnupp >> City University of Hong Kong >> Dept. of Neuroscience >> 31 To Yuen Street, >> Kowloon Tong >> Hong Kong >> >> https://auditoryneuroscience.com >> http://jan.schnupp.net >> >> >> On Mon, 15 Aug 2022 at 10:40, Petter Kallioinen < >> 000001c5645d28b7-dmarc-request@xxxxxxxx> wrote: >> >>> Dear Carlos, >>> I have used neuroscan a little and EGI a lot, but I do prefer Biosemi. >>> The system is more simple and modular than EGI. I have done about 250 >>> recordings with 4-6 year olds in pre-schools using Biosemi. While I do >>> think it is possible to have good signal in EGI, it is easier to >>> troubleshoot bad signals in Biosemi, usually a single or a few bad >>> electrodes that can be fixed with more gel. In EGI problems are often m= ore >>> vague and indirect. If you use Biosemi 64 channels with children, time = of >>> application can be an issue. Two well trained assistants could do it in >>> 15-20 minutes, but is is still an issue. Depending on your research >>> question 32 channels could be good enough and considerably faster. >>> >>> Customer support is fast but brief with Biosemi, and a lot of times I >>> have solved things based on forum discussions rather than direct suppor= t, I >>> am still more satisfied with support from Biosemi compared to EGI. Bios= emi >>> is more to the point and technical, whereas EGI has a slow and somewhat >>> bureaucratic support. >>> >>> Signal quality should be better with Biosemi active electrodes compared >>> to EGI, but I have actually not tested this thoroughly. When I have loo= ked >>> at amplitudes of MMN responses the effects have been quite similar betw= een >>> EGI and Biosemi. I was surprised by this but it could be a larger >>> difference in paradigms with fewer events. >>> >>> Best wishes! >>> /Petter Kallioinen, EEG technician at linguistics dept, Stockholm >>> University >>> >>> On 12 Aug 2022, at 17:20 , Carlos Benitez-Barrera < >>> 000001c4037ab8ae-dmarc-request@xxxxxxxx> wrote: >>> >>> Dear Auditory List, >>> >>> I am planning on purchasing an EEG system for my new lab at UW-Madison, >>> USA. I have been in contact with several EEG providers, and I=E2=80=99m= still >>> undecisive on which system would be best for my lab. I=E2=80=99m famili= ar with >>> Neuroscan and EGI, but I=E2=80=99m actually leaning towards Biosemi or = Brain >>> Products (Brain and Vision in the US). I run simple auditory paradigms = with >>> children (ages 3 to 14) and adults. The main characteristics that I=E2= =80=99m >>> looking for are (not necessarily in order): >>> >>> - Ease of use >>> - Prep cap time (important to minimize with children) >>> - Customer support >>> - Signal quality >>> >>> >>> I=E2=80=99m shooting for a 64-channel system. Also, I=E2=80=99m still h= esitating between >>> saline caps or gel caps. I heard that the Biosemi caps despite of being= gel >>> based are very fast to get going. >>> >>> Anyway, I=E2=80=99m just looking for some advice from any of you workin= g with >>> these systems. Any experiences or recommendations will help! >>> >>> Thank you in advance for your taking your time to reply! >>> >>> Sincerely, >>> Carlos >>> >>> >>> > --000000000000a4fcbb05e695caf5 Content-Type: text/html; charset="UTF-8" Content-Transfer-Encoding: quoted-printable <div dir=3D"rtl"><div dir=3D"ltr"><p class=3D"MsoNormal" dir=3D"LTR" style= =3D"direction:ltr;unicode-bidi:embed;margin:0cm 0cm 8pt;line-height:107%;fo= nt-size:11pt;font-family:Calibri,sans-serif">Hello again,</p> <p class=3D"MsoNormal" dir=3D"LTR" style=3D"direction:ltr;unicode-bidi:embe= d;margin:0cm 0cm 8pt;line-height:107%;font-size:11pt;font-family:Calibri,sa= ns-serif">The dithering process is related to the process of assigning a di= gital value to the analog incoming data. It is an intentionally applied form of noise, used to randomize quantization error. However, here it apparently creates &#39;spurious tones&#39; due to &#39;not-fully-damped resonance in = the feedback circuit&#39;. On the Fourier graph (when you zoom in quite a lot at high fr= equencies) it results in extra sharp &#39;needles&#39;, mainly at multiples of eight, = but also (less) at multiples of two. The needles do NOT diminish toward higher frequ= ency (they are &#39;of nearly infinite width&#39;), and therefore disturb more t= he higher one&#39;s &#39;treasure data&#39; - which do succumb to the 1/f rule - reside. These = technical details are abridged from Biosemi&#39;s responses to our questions upon encounterin= g the issue. </p> <p class=3D"MsoNormal" dir=3D"LTR" style=3D"direction:ltr;unicode-bidi:embe= d;margin:0cm 0cm 8pt;line-height:107%;font-size:11pt;font-family:Calibri,sa= ns-serif">It is not possible to filter this contamination out.</p> <p class=3D"MsoNormal" dir=3D"LTR" style=3D"direction:ltr;unicode-bidi:embe= d;margin:0cm 0cm 8pt;line-height:107%;font-size:11pt;font-family:Calibri,sa= ns-serif">In my study the sampling rate was 16384 Hz (Biosemi&#39;s Mode 7)= with 32+8 electrodes. I was looking (among other things) for brainstem FFR to 530 Hz = pure (and stable) tones. Due to presenting the stimulus in alternate polarities = (as recommended by the custom practice [but, btw, not by all researchers]), I w= as looking for the response (in the combined data of the two polarities) at 10= 60 Hz. This is definitely not a regular region of interest even to FFR researc= hers, who normally probe speech FFR, at about a quarter of this value; it would disturb them less (but perhaps worth checking anyway). Also, speech FFR wou= ld involve gliding frequencies, where you may also still be able to see the be= autiful, flexible response. In my case it disturbed more. And, unfortunately, I foun= d it after all the experiments had been conducted=E2=80=A6</p> <p class=3D"MsoNormal" dir=3D"LTR" style=3D"direction:ltr;unicode-bidi:embe= d;margin:0cm 0cm 8pt;line-height:107%;font-size:11pt;font-family:Calibri,sa= ns-serif">As I said, Biosemi seem to be on the verge of launching a new pro= duct which does not involve the same technology at all. This has been some time = since they said that. Hopefully, this will happen soon. </p> <p class=3D"MsoNormal" dir=3D"LTR" style=3D"direction:ltr;unicode-bidi:embe= d;margin:0cm 0cm 8pt;line-height:107%;font-size:11pt;font-family:Calibri,sa= ns-serif">Other than this issue, the data we collected with their equipment= is beautiful=E2=80=A6 :)</p><p class=3D"MsoNormal" style=3D"unicode-bidi:embed= ;margin:0cm 0cm 8pt;line-height:107%;font-size:11pt;font-family:Calibri,san= s-serif">Amos</p> <p class=3D"MsoNormal" dir=3D"LTR" style=3D"direction:ltr;unicode-bidi:embe= d;margin:0cm 0cm 8pt;line-height:107%;font-size:11pt;font-family:Calibri,sa= ns-serif">P.S. Alain: Of course we first checked if it is a light bulb or s= ome un-isolated cable etc or a bad electrode. But then Biosemi confirmed the pr= oblem resides in the ADC process.</p></div></div><br><div class=3D"gmail_quote"><= div dir=3D"rtl" class=3D"gmail_attr">=E2=80=AB=D7=91=D7=AA=D7=90=D7=A8=D7= =99=D7=9A =D7=99=D7=95=D7=9D =D7=95=D7=B3, 19 =D7=91=D7=90=D7=95=D7=92=D7= =B3 2022 =D7=91-10:05 =D7=9E=D7=90=D7=AA =E2=80=AAPetter Kallioinen=E2=80= =AC=E2=80=8F &lt;=E2=80=AA<a href=3D"mailto:petter@xxxxxxxx">petter@xxxxxxxx= su.se</a>=E2=80=AC=E2=80=8F&gt;:=E2=80=AC<br></div><blockquote class=3D"gma= il_quote" style=3D"margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,2= 04,204);padding-left:1ex"> <div style=3D"overflow-wrap: break-word;"> <div> <blockquote type=3D"cite"> <div dir=3D"rtl"> <div dir=3D"ltr">=C2=A0keep in mind that in the Biosemi ActiveTwo system a = not-so-widely-known problem exists, of the signal being contaminated by the= dithering process in the Sigma-Delta ADC box, at frequency-multiples relat= ed to the sampling rate.</div> </div> </blockquote> </div> <div><br> </div> I did not know about this. How high frequencies are we talking about here? = Is there a thorough description of the problem somewhere? <div><br> </div> <div>I=E2=80=99m not worried, but it is good to know...<br> <div><br> </div> <div>Thanks,</div> <div>Petter</div> <div> <div><br> <blockquote type=3D"cite"> <div>On 18 Aug 2022, at 18:25 , Amos Boasson &lt;<a href=3D"mailto:agboas@xxxxxxxx= MAIL.COM" target=3D"_blank">agboas@xxxxxxxx</a>&gt; wrote:</div> <br> <div> <div dir=3D"rtl"> <div dir=3D"ltr">Dear Carlos, and list members:</div> <div dir=3D"ltr">Carlos, keep in mind that in the Biosemi ActiveTwo system = a not-so-widely-known problem exists, of the signal being contaminated by t= he dithering process in the Sigma-Delta ADC box, at frequency-multiples rel= ated to the sampling rate.</div> <div dir=3D"ltr">This problem disturbs mainly if you are interested in spec= trum analysis at higher frequencies, as for examples in studies of the Freq= uency Following Response (FFR), where presentation of the stimulus in alter= nate polarities leads you to look for a response at double the stimulus frequency. Because of the 1/= f decrement, mechanical=C2=A0&#39;side-effects&#39; infiltrating the signal= , unremovable, are more and more disturbing. the higher your frequency regi= on of interest.</div> <div dir=3D"ltr">Biosemi intends to implement a whole different technology = in their next model (ActiveThree?), which would eliminate this problem, but= I have not seen it on their site yet.</div> <div dir=3D"ltr">This problem may not disturb some kinds of analysis, but y= ou may want to consider it.</div> <div dir=3D"ltr">Good luck with your new lab!</div> <div dir=3D"ltr">Sincerely, Amos Boasson</div> </div> <br> <div class=3D"gmail_quote"> <div dir=3D"rtl" class=3D"gmail_attr">=E2=80=AB=D7=91=D7=AA=D7=90=D7=A8=D7= =99=D7=9A =D7=99=D7=95=D7=9D =D7=93=D7=B3, 17 =D7=91=D7=90=D7=95=D7=92=D7= =B3 2022 =D7=91-7:07 =D7=9E=D7=90=D7=AA =E2=80=AAJan Schnupp=E2=80=AC=E2=80= =8F &lt;=E2=80=AA<a href=3D"mailto:000000e042a1ec30-dmarc-request@xxxxxxxx= ill.ca" target=3D"_blank">000000e042a1ec30-dmarc-request@xxxxxxxx</a= >=E2=80=AC=E2=80=8F&gt;:=E2=80=AC<br> </div> <blockquote class=3D"gmail_quote" style=3D"margin:0px 0px 0px 0.8ex;border-= left:1px solid rgb(204,204,204);padding-left:1ex"> <div dir=3D"ltr">I cannot recommend strongly enough AGAINST the EGI setup. = I had inherited one of their systems. It was terribly buggy. Lost parts of = the signal. Lost triggers. My PhD student lost many months trying to debug = the device or find work-arounds. Their customer service was unresponsive. It was simply terrible. What resc= ued my student was that we were able to get an ANT EEGo system from a frien= d, which perhaps hasn&#39;t the greatest S/N but it was quite adequate, and= at least it was relatively straight-forward to get to work as advertised and we got some nice studies done with it. AN= T now also offer a=C2=A0sponge cap for their EEGo system which can reduce p= rep time. We ordered one but we=C2=A0haven&#39;t received it yet so I can&#= 39;t tell you whether=C2=A0the S/N is adequate.=C2=A0 <div>Under absolutely no circumstances would I ever again waste a single do= llar or minute of my time on anything EGI.=C2=A0</div> <div><br> </div> <div>Best wishes,</div> <div><br> </div> <div>Jan<br> <div><br clear=3D"all"> <div> <div dir=3D"ltr"> <div dir=3D"ltr"> <div> <div dir=3D"ltr"> <div> <div dir=3D"ltr"> <div dir=3D"ltr"> <div dir=3D"ltr"> <div dir=3D"ltr"> <div style=3D"font-size:12.8px"><br> </div> <div style=3D"font-size:12.8px">---------------------------------------</di= v> <div style=3D"font-size:12.8px">Prof Jan Schnupp<br> City University of Hong Kong<br> Dept. of Neuroscience</div> <div> <div style=3D"font-size:12.8px">31 To Yuen Street,=C2=A0</div> <div style=3D"font-size:12.8px"><span style=3D"font-size:12.8px">Kowloon To= ng</span></div> <div style=3D"font-size:12.8px">Hong Kong</div> <div style=3D"font-size:12.8px"><br> </div> <a href=3D"https://auditoryneuroscience.com/" target=3D"_blank">https://aud= itoryneuroscience.com</a></div> <div><a href=3D"http://jan.schnupp.net/" target=3D"_blank">http://jan.schnu= pp.net</a></div> </div> </div> </div> </div> </div> </div> </div> </div> </div> </div> <br> </div> </div> </div> <br> <div class=3D"gmail_quote"> <div dir=3D"ltr" class=3D"gmail_attr">On Mon, 15 Aug 2022 at 10:40, Petter = Kallioinen &lt;<a href=3D"mailto:000001c5645d28b7-dmarc-request@xxxxxxxx= l.ca" target=3D"_blank">000001c5645d28b7-dmarc-request@xxxxxxxx</a>&= gt; wrote:<br> </div> <blockquote class=3D"gmail_quote" style=3D"margin:0px 0px 0px 0.8ex;border-= left:1px solid rgb(204,204,204);padding-left:1ex"> <div>Dear Carlos, <div>I have used neuroscan a little and EGI a lot, but I do prefer Biosemi.= The system is more simple and modular than EGI. I have done about 250 reco= rdings with 4-6 year olds in pre-schools using Biosemi. While I do think it= is possible to have good signal in EGI, it is easier to troubleshoot bad signals in Biosemi, usuall= y a single or a few bad electrodes that can be fixed with more gel. In EGI = problems are often more vague and indirect. If you use Biosemi 64 channels = with children, time of application can be an issue. Two well trained assistants could do it in 15-20 minutes,= but is is still an issue. Depending on your research question 32 channels = could be good enough and considerably faster.=C2=A0</div> <div><br> </div> <div>Customer support is fast but brief with Biosemi, and a lot of times I = have solved things based on forum discussions rather than direct support, I= am still more satisfied with support from Biosemi compared to EGI. Biosemi= is more to the point and technical, whereas EGI has a slow and somewhat bureaucratic support.</div> <div><br> </div> <div>Signal quality should be better with Biosemi active electrodes compare= d to EGI, but I have actually not tested this thoroughly. When I have looke= d at amplitudes of MMN responses the effects have been quite similar betwee= n EGI and Biosemi. I was surprised by this but it could be a larger difference in paradigms with fe= wer events.=C2=A0</div> <div><br> </div> <div>Best wishes!</div> <div>/Petter Kallioinen, EEG technician at linguistics dept, Stockholm Univ= ersity =C2=A0<br> <div><br> <blockquote type=3D"cite"> <div>On 12 Aug 2022, at 17:20 , Carlos Benitez-Barrera &lt;<a href=3D"mailt= o:000001c4037ab8ae-dmarc-request@xxxxxxxx" target=3D"_blank">000001c= 4037ab8ae-dmarc-request@xxxxxxxx</a>&gt; wrote:</div> <br> <div> <div style=3D"font-family:Helvetica;font-size:14px;font-style:normal;font-v= ariant-caps:normal;font-weight:normal;letter-spacing:normal;text-align:star= t;text-indent:0px;text-transform:none;white-space:normal;word-spacing:0px;t= ext-decoration:none"> <div style=3D"margin:0in 0in 0.0001pt;font-size:12pt;font-family:Calibri,sa= ns-serif"> <span style=3D"font-size:11pt">Dear Auditory List,</span><span><u></u><u></= u></span></div> <div style=3D"margin:0in 0in 0.0001pt;font-size:12pt;font-family:Calibri,sa= ns-serif"> <span style=3D"font-size:11pt">=C2=A0</span><span><u></u><u></u></span></di= v> <div style=3D"margin:0in 0in 0.0001pt;font-size:12pt;font-family:Calibri,sa= ns-serif"> <span style=3D"font-size:11pt">I am planning on purchasing an EEG system fo= r my new lab at UW-Madison, USA. I have been in contact with several EEG pr= oviders, and I=E2=80=99m still undecisive on which system would be best for= my lab. I=E2=80=99m familiar with Neuroscan and EGI, but I=E2=80=99m actually leaning towards Biosemi or Brain Product= s (Brain and Vision in the US). I run simple auditory paradigms with childr= en (ages 3 to 14) and adults. The main characteristics that I=E2=80=99m loo= king for are (not necessarily in order):</span><span><u></u><u></u></span><= /div> <ul type=3D"disc" style=3D"margin-bottom:0in;margin-top:0in"> <li class=3D"MsoNormal" style=3D"margin:0in 0in 0.0001pt;font-size:12pt;fon= t-family:Calibri,sans-serif"> <span style=3D"font-size:11pt">Ease of use</span><u></u><u></u></li><li cla= ss=3D"MsoNormal" style=3D"margin:0in 0in 0.0001pt;font-size:12pt;font-famil= y:Calibri,sans-serif"> <span style=3D"font-size:11pt">Prep cap time (important to minimize with ch= ildren)</span><u></u><u></u></li><li class=3D"MsoNormal" style=3D"margin:0i= n 0in 0.0001pt;font-size:12pt;font-family:Calibri,sans-serif"> <span style=3D"font-size:11pt">Customer support</span><u></u><u></u></li><l= i class=3D"MsoNormal" style=3D"margin:0in 0in 0.0001pt;font-size:12pt;font-= family:Calibri,sans-serif"> <span style=3D"font-size:11pt">Signal quality</span><u></u><u></u></li></ul= > <div style=3D"margin:0in 0in 0.0001pt;font-size:12pt;font-family:Calibri,sa= ns-serif"> <span style=3D"font-size:11pt">=C2=A0</span><span><u></u><u></u></span></di= v> <div style=3D"margin:0in 0in 0.0001pt;font-size:12pt;font-family:Calibri,sa= ns-serif"> <span style=3D"font-size:11pt">I=E2=80=99m shooting for a 64-channel system= . Also, I=E2=80=99m still hesitating between saline caps or gel caps. I hea= rd that the Biosemi caps despite of being gel based are very fast to get go= ing.=C2=A0</span><span><u></u><u></u></span></div> <div style=3D"margin:0in 0in 0.0001pt;font-size:12pt;font-family:Calibri,sa= ns-serif"> <span style=3D"font-size:11pt">=C2=A0</span><span><u></u><u></u></span></di= v> <div style=3D"margin:0in 0in 0.0001pt;font-size:12pt;font-family:Calibri,sa= ns-serif"> <span style=3D"font-size:11pt">Anyway, I=E2=80=99m just looking for some ad= vice from any of you working with these systems. Any experiences or recomme= ndations will help!</span><span><u></u><u></u></span></div> <div style=3D"margin:0in 0in 0.0001pt;font-size:12pt;font-family:Calibri,sa= ns-serif"> <span style=3D"font-size:11pt">=C2=A0</span><span><u></u><u></u></span></di= v> <div style=3D"margin:0in 0in 0.0001pt;font-size:12pt;font-family:Calibri,sa= ns-serif"> <span style=3D"font-size:11pt">Thank you in advance for your taking your ti= me to reply!</span><span><u></u><u></u></span></div> <div style=3D"margin:0in 0in 0.0001pt;font-size:12pt;font-family:Calibri,sa= ns-serif"> <span style=3D"font-size:11pt">=C2=A0</span><span><u></u><u></u></span></di= v> <div style=3D"margin:0in 0in 0.0001pt;font-size:12pt;font-family:Calibri,sa= ns-serif"> <span style=3D"font-size:11pt">Sincerely,</span><span><u></u><u></u></span>= </div> <div style=3D"margin:0in 0in 0.0001pt;font-size:12pt;font-family:Calibri,sa= ns-serif"> <span style=3D"font-size:11pt">Carlos</span></div> </div> </div> </blockquote> </div> <br> </div> </div> </blockquote> </div> </blockquote> </div> </div> </blockquote> </div> <br> </div> </div> </div> </blockquote></div> --000000000000a4fcbb05e695caf5--


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