From paulmacdnc at att.net Wed Feb 7 13:33:23 2024 From: paulmacdnc at att.net (The MacDougals) Date: Wed, 7 Feb 2024 14:33:23 -0500 Subject: [TriEmbed] Monthly meeting 2/12/2024 References: <0d2b01da59fc$84304ec0$8c90ec40$.ref@att.net> Message-ID: <0d2b01da59fc$84304ec0$8c90ec40$@att.net> We will have our normal monthly meeting on Monday 2/12/24 at 7:00 pm Agenda: - Welcome - Announcements - P.O.T.M. - Show and Tell The plan for this month is to use https://meet.jit.si/TriEmbed ---> Paul -------------- next part -------------- An HTML attachment was scrubbed... URL: From jwet at mindspring.com Thu Feb 8 07:34:50 2024 From: jwet at mindspring.com (jwet) Date: Thu, 08 Feb 2024 08:34:50 -0500 Subject: [TriEmbed] Large pelican Cases at Habitat Cary Message-ID: I saw two large, 30 x 18 x12 approx. Pelican Cases in nice shape for $79.? Some scuffs and sticker rash but easily cleaned up They are checkable as luggage, no foam or anything inside.? Color black, nice latches and hinge.? I'm trying to thin out my stuff but can live vicariously through you.Sent from my Verizon, Samsung Galaxy smartphone -------------- next part -------------- An HTML attachment was scrubbed... URL: -------------- next part -------------- A non-text attachment was scrubbed... Name: 20240207_133831.jpg Type: image/jpeg Size: 3311035 bytes Desc: not available URL: From jwet at mindspring.com Thu Feb 8 08:33:14 2024 From: jwet at mindspring.com (John Wettroth) Date: Thu, 8 Feb 2024 09:33:14 -0500 Subject: [TriEmbed] Large Pelican Case at Habitat Store Cary Message-ID: <009501da5a9b$c0cbe6b0$4263b410$@mindspring.com> I saw two nice looking large 18 x30 x12 " luggage sized Pelican cases. 2 Wheels on back corner. Scuffs and some sticker rash but would clean up easily. $79 each, two available yesterday. Regards, John M. Wettroth E: jwet at mindspring.com M: (919) 349-9875 H: (984) 329-5420 -------------- next part -------------- A non-text attachment was scrubbed... Name: pelican crop.jpg Type: image/jpeg Size: 251156 bytes Desc: not available URL: From charlesryanwest at gmail.com Tue Feb 13 07:55:07 2024 From: charlesryanwest at gmail.com (Charles West) Date: Tue, 13 Feb 2024 08:55:07 -0500 Subject: [TriEmbed] GoodBot at RARSFest Message-ID: Hello All, I'm not going to be able to make it on April 6th due to a prior commitment (father/daughter Y guides camp trip). However, maybe I could make a display and demo? I could have a poster with the QR code for the discord and have a RC controllable instance of the robot if anyone wants to take charge of it. Would that be OK? Thanks, Charlie -------------- next part -------------- An HTML attachment was scrubbed... URL: From carl.nobile at gmail.com Tue Feb 13 19:58:49 2024 From: carl.nobile at gmail.com (Carl Nobile) Date: Tue, 13 Feb 2024 20:58:49 -0500 Subject: [TriEmbed] GoodBot at RARSFest In-Reply-To: References: Message-ID: Charlie, That sounds good to me. At least you can get some advertisement even if you can't come. ~Carl On Tue, Feb 13, 2024 at 8:55?AM Charles West via TriEmbed < triembed at triembed.org> wrote: > Hello All, > > I'm not going to be able to make it on April 6th due to a prior commitment > (father/daughter Y guides camp trip). However, maybe I could make a > display and demo? > > I could have a poster with the QR code for the discord and have a RC > controllable instance of the robot if anyone wants to take charge of it. > > Would that be OK? > > Thanks, > Charlie > _______________________________________________ > Triangle, NC Embedded Interest Group mailing list > > To post message: TriEmbed at triembed.org > List info: http://mail.triembed.org/mailman/listinfo/triembed_triembed.org > TriEmbed web site: https://TriEmbed.org > To unsubscribe, click link and send a blank message: mailto: > unsubscribe-TriEmbed at bitser.net?subject=unsubscribe > Searchable email archive available at > https://www.mail-archive.com/triembed at triembed.org/ > > -- -------------------------------------------------------------- Carl J. Nobile (Software Engineer/API Design) carl.nobile at gmail.com -------------------------------------------------------------- -------------- next part -------------- An HTML attachment was scrubbed... URL: From paulmacdnc at att.net Wed Feb 14 14:53:36 2024 From: paulmacdnc at att.net (The MacDougals) Date: Wed, 14 Feb 2024 15:53:36 -0500 Subject: [TriEmbed] P.O.T.M. preliminary report References: <009e01da5f87$e224fef0$a66efcd0$.ref@att.net> Message-ID: <009e01da5f87$e224fef0$a66efcd0$@att.net> The Problem Of The Month this month was how to lower the volume on a childs toy. The speaker is driven from two pins of the processor. The DC resistance of the speaker is 9.3 Ohms. Several suggestions were made on how to reduce the volume. I will report here on the first few things I tried. I downloaded an app on my iPhone to measure loudness. The app was very specific in stating that the values measured were approximate. LAeq Max LCPeak TWA unmodified 85.90 91.20 102.40 52.00 22 ohm in series 80.00 86.60 96.60 46.20 47 ohm in series 74.00 80.70 90.80 xxx 47 uf in series 87.70 93.50 104.20 55.30 1 uf in series 76.30 83.10 95.40 xxx To my untrained ear, I found the 1 uf to be a good result. I did not notice a change in the tonal qualities, but I am untrained and old (so I don't hear high frequencies). ---> Paul -------------- next part -------------- An HTML attachment was scrubbed... URL: From triembed at undecidedgames.net Mon Feb 19 09:48:59 2024 From: triembed at undecidedgames.net (Brian) Date: Mon, 19 Feb 2024 10:48:59 -0500 Subject: [TriEmbed] P.O.T.M. preliminary report In-Reply-To: <009e01da5f87$e224fef0$a66efcd0$@att.net> References: <009e01da5f87$e224fef0$a66efcd0$.ref@att.net> <009e01da5f87$e224fef0$a66efcd0$@att.net> Message-ID: 100 dB peak from a toy!! That sounds like a reason to complain to some governing body somewhere. Armchair audio engineer here with a few tips (and I wasn't in the meeting, so forgive me if I'm repeating things that have already been said). A capacitor's impedance is inversely proportional to frequency. A single cap in series will attenuate low frequencies more than high frequencies. Your grown-up ears may not be able to tell the difference, but the toy probably uses PCM to generate sound and likely has little to no output filtering of its own, so that sound is going to have an above-average amount of high-frequency energy. The "common" way to peel back the power going to a speaker is with an arrangement of resistors known as an L-pad. This is the combination of a series resistance and a parallel resistance that keeps the total impedance seen by the output circuit constant, while reducing the current flowing in the speaker. There are calculators available on the web where you punch in the speaker impedance and the desired reduction in decibels, and it tells you the resistor values to use. Note: Audio circuit impedances (including speakers) are nominally measured at 1 kHz. A speaker, being an inductor, will measure a bit higher at 1 kHz than at DC. All of that said, given it's being directly driven by IC pins, the impedance probably isn't as critical. HTH! -B On 2/14/24 15:53, The MacDougals via TriEmbed wrote: > The Problem Of The Month this month was how to lower the volume on a > childs toy. > > The speaker is driven from two pins of the processor.? The DC resistance > of the speaker is 9.3 Ohms. > > Several suggestions were made on how to reduce the volume.? I will > report here on the first few things I tried. > > I downloaded an app on my iPhone to measure loudness. > > The app was very specific in stating that the values measured were > approximate. > > > > LAeq > > > > Max > > > > LCPeak > > > > TWA > > unmodified > > > > 85.90 > > > > 91.20 > > > > 102.40 > > > > 52.00 > > 22 ohm in series > > > > 80.00 > > > > 86.60 > > > > 96.60 > > > > 46.20 > > 47 ohm in series > > > > 74.00 > > > > 80.70 > > > > 90.80 > > > > xxx > > 47 uf in series > > > > 87.70 > > > > 93.50 > > > > 104.20 > > > > 55.30 > > 1 uf in series > > > > 76.30 > > > > 83.10 > > > > 95.40 > > > > xxx > > To my untrained ear, I found the 1 uf to be a good result.? I did not > notice a change in the tonal qualities, but I am untrained and old (so I > don?t hear high frequencies). > > ---> Paul > > > _______________________________________________ > Triangle, NC Embedded Interest Group mailing list > > To post message: TriEmbed at triembed.org > List info: http://mail.triembed.org/mailman/listinfo/triembed_triembed.org > TriEmbed web site: https://TriEmbed.org > To unsubscribe, click link and send a blank message: mailto:unsubscribe-TriEmbed at bitser.net?subject=unsubscribe > Searchable email archive available at https://www.mail-archive.com/triembed at triembed.org/ > From charlesryanwest at gmail.com Mon Feb 19 21:00:22 2024 From: charlesryanwest at gmail.com (Charles West) Date: Mon, 19 Feb 2024 22:00:22 -0500 Subject: [TriEmbed] What makes a great hobbyist robot? Message-ID: Hello all, I'm elbow deep in the new Mk5 chassis design for the 4 wheel outdoor Goodbot robot and was wondering if you guys might be willing to give me some feedback. The "big idea" of the Mk5 chassis is modularity and modability. That's currently being expressed in 2 ways: 1. Most all of the sensors and compute can be popped out, fiddled with and entirely replaced super easily. You can also remove the big battery, battery holder and motor control PCB just by unscrewing some things and disconnecting some wires, making it really easy to access the motors if you find it too cramped work with them otherwise. 2. I'm putting brass threaded inserts all over the place. You can mount things onto the front, back or sides just by bolting it on with some M4 bolts. No modification required, you just bolt it on. However, I'm a bit stuck with the cap. There's a number of different ways I could mount it: 1. Screws in. Has a bunch (perhaps a grid) of threaded inserts on top so that you mount stuff on top easily. 2. Friction fit. Has tabs with rubber on them so that you can just pull it on and off with a strong enough sustained tug vertically. Easier to take on/off but your stuff might not be as securely mounted if you put it on the lid (sensors probably fine, a mini fridge less so). 3. Magnet mount. Has magnets press fitted into the lid and the robot. Least secure option, but easy removal/replacement and it's cool. Given the way it's constructed, I could see eventually offering all of these options (and other custom designed lids/mounting methods. However, what do you think would see the most use? Also, what do you think of the "brass inserts everywhere so modding/mounting is easy" idea? Thanks, Charlie -------------- next part -------------- An HTML attachment was scrubbed... URL: From mrglenasmith at gmail.com Tue Feb 20 06:54:41 2024 From: mrglenasmith at gmail.com (Glen Smith) Date: Tue, 20 Feb 2024 07:54:41 -0500 Subject: [TriEmbed] What makes a great hobbyist robot? In-Reply-To: References: Message-ID: I would use the brass insert everywhere method - especially if you can standardize as best you can on the spacing. If I recall correctly this is potentially going to be a fair distance from an operator, it would not make me happy to discover an accessory has fallen off or been removed when the 'bot was out of my full observation. Having the inserts also means that the other two options are possible with an interposing layer: "Attach the EZ-Mag-Mount (tm) anywhere on the standardized grid of threaded points on Goodbot for those peripherals that may be removed frequently." Glen On Mon, Feb 19, 2024 at 10:00?PM Charles West via TriEmbed < triembed at triembed.org> wrote: > Hello all, > > I'm elbow deep in the new Mk5 chassis design for the 4 wheel outdoor > Goodbot robot and was wondering if you guys might be willing to give me > some feedback. The "big idea" of the Mk5 chassis is modularity and > modability. That's currently being expressed in 2 ways: > 1. Most all of the sensors and compute can be popped out, fiddled with and > entirely replaced super easily. You can also remove the big battery, > battery holder and motor control PCB just by unscrewing some things and > disconnecting some wires, making it really easy to access the motors if you > find it too cramped work with them otherwise. > 2. I'm putting brass threaded inserts all over the place. You can mount > things onto the front, back or sides just by bolting it on with some M4 > bolts. No modification required, you just bolt it on. > > However, I'm a bit stuck with the cap. There's a number of different ways > I could mount it: > 1. Screws in. Has a bunch (perhaps a grid) of threaded inserts on top so > that you mount stuff on top easily. > 2. Friction fit. Has tabs with rubber on them so that you can just pull > it on and off with a strong enough sustained tug vertically. Easier to > take on/off but your stuff might not be as securely mounted if you put it > on the lid (sensors probably fine, a mini fridge less so). > 3. Magnet mount. Has magnets press fitted into the lid and the robot. > Least secure option, but easy removal/replacement and it's cool. > > Given the way it's constructed, I could see eventually offering all of > these options (and other custom designed lids/mounting methods. However, > what do you think would see the most use? > > Also, what do you think of the "brass inserts everywhere so > modding/mounting is easy" idea? > > Thanks, > Charlie > _______________________________________________ > Triangle, NC Embedded Interest Group mailing list > > To post message: TriEmbed at triembed.org > List info: http://mail.triembed.org/mailman/listinfo/triembed_triembed.org > TriEmbed web site: https://TriEmbed.org > To unsubscribe, click link and send a blank message: mailto: > unsubscribe-TriEmbed at bitser.net?subject=unsubscribe > Searchable email archive available at > https://www.mail-archive.com/triembed at triembed.org/ > > -------------- next part -------------- An HTML attachment was scrubbed... URL: From carl.nobile at gmail.com Thu Feb 22 17:26:39 2024 From: carl.nobile at gmail.com (Carl Nobile) Date: Thu, 22 Feb 2024 18:26:39 -0500 Subject: [TriEmbed] I've just published the TriEmbed meeting from 2024-02-12 Message-ID: Hi all, I just published the most recent TriEmbed meeting that was on Jutsi. I've also added in the description the update that Paul sent in email. https://youtu.be/bnYB00pQyBs ~Carl -------------------------------------------------------------- Carl J. Nobile (Software Engineer/API Design) carl.nobile at gmail.com -------------------------------------------------------------- -------------- next part -------------- An HTML attachment was scrubbed... URL: From scottghall1 at gmail.com Wed Feb 28 14:24:36 2024 From: scottghall1 at gmail.com (Scott Hall) Date: Wed, 28 Feb 2024 15:24:36 -0500 Subject: [TriEmbed] Job Opportunity: Anybody looking for a job in electrical engineering? Message-ID: I just got hired for a contract with a medical device company, Gilero, and they are looking for an additional person -- you would work on contract through Triple Crown Consulting. *Description:* Design and develop new electromechanical drug delivery and medical devices to improve the safety and well-being of patients: - Develop electrical systems for medical devices, from concept to prototype through release for manufacturing and provide ongoing post-launch support - Design mixed signal, analog, power, and digital circuit design including schematic capture and layout of PCBAs - Prepare detailed block diagrams, circuit schematics and component specifications - Test and debug new hardware for medical device safety and EMC standards - Support custom firmware development and testing - Perform high-level circuit simulations - (and more) *Skills/Qualifications:* - BS in Engineering, 4-year technical degree or applicable experience - 5 - 12 years relevant experience, preferred - Proficiency in Altium Designer - Experience using multimeters, oscilloscopes, digital spectrum analyzers, and other test equipment for test and debug of hardware - Experience reading, understanding, and creating block diagrams, electrical schematics,and board layouts - Experience conducting/leading electrical compliance testing - Working knowledge of medical device regulations (FDA/ISO) - Experience with design for medical safety IEC 60601-1 and EMC standards such as IEC 60601-1-2 for complex medical systems, preferred - Experience with control systems, preferred - Experience with communication protocols such as UART, I2C, SPI, USB, BLE, preferred - Familiarity with embedded software and C language, preferred - Experience with embedded system development using a variety of microcontrollers *Contact:* Pirelli Pandac, recruiter at Triple Crown, 408-680-2583, ppandac at tripleco.com Please acknowledge me so I can garner referral points. -- Scott G. Hall Raleigh, NC, USA scottghall1 at gmail.com *Although kindness is rarely a job, no matter what you do it's always an option.* -------------- next part -------------- An HTML attachment was scrubbed... URL: