Friends and your projects - Page 1
Forum section: electronics / general

author: Wilksey
author_rank: Super Contributor
timestamp: October 03, 2021, 11:23:17 pm
content: I'm sure you have all been there, you design something, with no real intention to sell them but for a personal need and you get someone that wants one, you say sure, add a few pennies for the trouble of you putting it together and they baulk at the cost.So, to add some "meat" to my post, I have a Nexus dashcam that has some fancy parking mode, but it means that it has to be connected to a permanent live in the car, the dashcam says it'll turn off if the battery voltage gets to 11.2V, that is far too low for my liking, so I decided to put together a simple PCB that has a voltage divider a PIC12 and a relay to turn off the power if the voltage gets to 12V and stays off until it sees a voltage above 12.6V, it has a fuse and TVS as well as a few jelly bean components, and for my purposes it works well, I am planning for V2 to use a MOSFET for the switching instead of a relay and have a MOSFET for reverse polarity protection, the PIC ADC is good enough for what I need and the measurement between the ADC and multimeter is close enough for me, I store the values for OFF and ON in E2 so I can change them via UART if I need to, I used a Chinese PCB manufacturer and have 5 PCB's made and have a few spare as I used 3 of them for my own use, and the components I just bought from Farnell here in the UK, so they are not the cheapest but they were readily available and delivered within a few days, so the individual cost is around £25-£30 for raw component cost, I also found some small plastic boxes at a local hardware store that fitted quite well.Now I was showing a friend the dashcam itself as it has a connection for a rear camera too and I was explaining to him about how I wired it it and how the parking mode worked and the conversation came around to my little "protection" box, and he asked if I would be willing to make one for him, and I said sure, i'll let you have one for the cost of the parts plus a bit of soldering / assembly time, he said that was fair and i'd let him know the actual price I would charge him.I said I'd let him have one and help him install it but as I got the parts from a UK supplier it would be around £35, which I thought £5 to solder and assemble it was cheap, mostly SMT in anycase, and takes about 20 - 30 mins with programming / testing of the PIC. I hadn't heard anything back from him then he messages me this afternoon saying he's found one on eBay for £10 (from China) that is sold as a battery protector for a car and he has bought one so he doesn't need mine, I looked at the link he sent and it cuts the voltage at 11.5V which I think is too low still, and I looked at the relay (it comes bare board not boxed) and the one I used on mine draws 16mA as 12V the one on the Chinese one pulls 80mA at 12V, no fuse, no TVS and what I can only assume is a comparator, so I just said to him "Good luck", it doesn't bother me that he bought the Chinese one as he asked me if I would sell him one, I did it for myself not to sell.I don't manufacturer stuff to sell, but I can only imagine that you just can't do consumer type stuff as people will opt to buy from China cheaper, you get a small discount for buying bulk in the UK but it only works out to about £4 - £5 if you buy something like 10k parts from them, is it only specialist items that you can make money on if buying from local electronic component retailers?I was curious to know if anyone else has had this kind of thing happen to them and what their reponses were.

author: retiredfeline
author_rank: Frequent Contributor
timestamp: October 03, 2021, 11:51:59 pm
content: Fortunately (for both them and me) my friends show no interest whatsoever in my projects.But seriously I understand your situation. I would always steer people towards off-the-shelf solutions in the first instance, both for hardware and software. Life's too short to spend on product support.

author: BrokenYugo
author_rank: Super Contributor
timestamp: October 04, 2021, 12:09:56 am
content: Most people just aren't worth dealing with in that regard, they simply aren't compatible with such a casual business relationship. I think I've got one friend and one or two family members who actually take my advice on anything I'm at all knowledgeable on and pay up if we've agreed I'm going to sell them some good or service in the future.

author: andy3055
author_rank: Super Contributor
timestamp: October 04, 2021, 12:43:45 am
content: My situ is a bit different. I have very few friends with whom I talk tech. One of them listens to me and takes advice. The other is an enthusiast who has limited electronics knowledge to whom I gift a lot of things. I fix things free for him. All my old tech stuff I give him to keep or pass on. There are only a few things left behind I am trying to identify to dispose which I know are of no interest to him. There is absolutely no money involved as he is a comparatively poor guy who treats me like as if I am his dad! Comes running any time I need help. A couple of years back he kept my wife calm in the hospital when I had a major surgery! Now, my wife is another kind. Never wants to take my advice but will take the same advice from an outsiderStrange creature.

author: Wilksey
author_rank: Super Contributor
timestamp: October 04, 2021, 01:00:40 am
content: Yeah I don't tend to tout my projects between friends and family, I make stuff to give to them like light up things for the kids etc and I make stuff that I need like the project I mentioned above, I had already told my friend that I had made this "gadget" and for what reason, he's into I.T. and electronic stuff, buying, not making I should add, so I thought he might be interested in it, he has taken an interest in some of my other projects but never asked if I could sell him one before, but he casually dropped in "I could do with one of those for when I get my dashcam, can I take one off your hands i'll pay you for it", and I just kind of said "Yeah, sure" I mean what else do you do on the spot to a friend who you have just told you had 5 boards made and used 3.I just hate wasting my time pricing everything up and then to be told they found a cheaper one on eBay which does pretty much the same as the dashcam itself, especially since he asked me.I'll certainly not be confessing to having "extra" next time!!

author: andy3055
author_rank: Super Contributor
timestamp: October 04, 2021, 02:03:37 am
content: One way to avoid the problem is to get the money in advance.

author: Wilksey
author_rank: Super Contributor
timestamp: October 04, 2021, 09:15:27 am
content: It's a tough thing asking friends / family for downpayment, I always think they would see it as a trust issue, although it is in reality as they are the ones who mess you around in the first place!In this instance only a bit of time was wasted calculating the individual price as I hadn't started building anything yet, I will probably build the other 2 up in my own time, and probably end up giving them away.It's a pain in the arse selling stuff to friends and family as they almost want it for free and lifetime support, which is why I avoid it if I can, was just a on the spot situation with this one.

author: andy3055
author_rank: Super Contributor
timestamp: October 04, 2021, 04:49:01 pm
content: Or, you can give the BOM and have them buy the parts!

author: rstofer
author_rank: Super Contributor
timestamp: October 04, 2021, 06:03:44 pm
content: Quote from: andy3055 on October 04, 2021, 04:49:01 pmAnd they buy 'floor sweepings' from China and you spend days trying to get it to work only to wind up buying replacement parts from a reputable supplier.

author: andy3055
author_rank: Super Contributor
timestamp: October 04, 2021, 06:51:00 pm
content: That is easy to fix. One can always stipulate where the parts should come from. If not, it is a no go. Main idea is to come to the understanding that the project goes forward on your terms and not the end user's. Take it or leave it unless you do it out of kindness on your own dime.

author: Bud
author_rank: Super Contributor
timestamp: October 04, 2021, 07:33:23 pm
content: Do not get into money relationships with friends, that is a recipe for disaster.

author: Wilksey
author_rank: Super Contributor
timestamp: October 04, 2021, 10:55:44 pm
content: The trouble is you can get so much crap from China for pittance that people do not see the value in anything anymore, and when it breaks it's just said "yeah, well it was a cheap one from China".I liken it to NTSC - Never the same colo(u)r, or never twice the same color, but from China it is "Never twice the same component", whilst "batches" can have different tolerances, they usually contain the same circuit unlike some experiences from China.

author: Circlotron
author_rank: Super Contributor
timestamp: October 04, 2021, 11:07:43 pm
content: Quote from: Wilksey on October 03, 2021, 11:23:17 pmWhatever you do, don't install it or have anything to do with it. When it sets his car on fire it will be your fault for sure!

author: Wilksey
author_rank: Super Contributor
timestamp: October 05, 2021, 12:09:24 am
content: Quote from: Circlotron on October 04, 2021, 11:07:43 pmHaha, yeah, I am not going to do anything with it, he can take it to one of the local automotive shops to get it installed or ask the place he buys the cams from to do it for him. If he does ask i'll be too busy to help.

author: james_s
author_rank: Super Contributor
timestamp: October 05, 2021, 01:23:43 am
content: I've built things as gifts for friends and family but I've never tried selling it to them.I have had a handful of random people contact me about my DS1742 adapter board and nobody has balked at the price, although I really don't want to be in the business of assembling widgets.

author: station240
author_rank: Unknown
timestamp: October 05, 2021, 05:56:36 am
content: Quote from: Wilksey on October 04, 2021, 10:55:44 pmI ordered 5x of a particular module that outputs 5V via USB, 2x output 4.95V, 3x output 5.3V (outside of USB spec).Measured the circuit, 3x have a higher voltage zener.So I ordered a roll of replacement zener diodes from RS, so I can fix the modules later when I need them, yup they screwed up too, wrong value again.

author: Wilksey
author_rank: Super Contributor
timestamp: October 05, 2021, 08:43:08 am
content: Quote from: james_s on October 05, 2021, 01:23:43 amNo, I haven't actively tried selling my stuff, I usually make things like LED Christmas ornaments, which I just give away to family and friends, I usually just say if they want to give anything for it then to donate to charity but it is not mandated and it is not a set amount.I don't know about others but SOME of my F+F almost insist on trying to give me something for the gift, which is when I just tell them to donate to charity if they feel the need.To be honest the only thing that has "gone wrong" with my gifts so far is the batteries have run out, some think that the batteries will last for an eternity because the ones in their TV remote do.

author: Wilksey
author_rank: Super Contributor
timestamp: October 05, 2021, 08:48:05 am
content: Quote from: station240 on October 05, 2021, 05:56:36 amOh don't get me wrong I order Chinese stuff but I like to think that I have enough knowledge to test the way you have tested them, and fix and find the failure point, most people who are no EE's who buy this stuff just buys it and whacks it in. We're talking a £5 12V - 5VUSB car adaptor with questionable regulation for a £1000 phone in some cases, and I dare say in most cases the phone will be fine, but still.There are some really good and cheap Chinese components and kits out there and if they do not use the original IC then they are a bloody good clone.

author: Wilksey
author_rank: Super Contributor
timestamp: October 05, 2021, 11:36:04 am
content: Quote from: wraper on October 05, 2021, 09:05:41 amSo true!

author: andy3055
author_rank: Super Contributor
timestamp: October 05, 2021, 09:39:44 pm
content: That is a great video. He speaks all we think/feel about!

author: james_s
author_rank: Super Contributor
timestamp: October 05, 2021, 11:59:19 pm
content: I agree with a lot of that. On the flip side I sometimes wish family members would ask me about something rather than just taking care of it themselves. I remember my grandmother had major appliances replaced several times without even asking me if I could look at the old ones. I would have been more than happy to fix the old ones because they were cool vintage things and it's the sort of thing I enjoy doing. With most of my family it just works out, I help them out with things I can do and they help me out with things I can do. I have several friends that are similar, they are useful to me in one way or another and I am useful to them, I try to keep the favor bank loaded up so things are more or less even. Generally it doesn't seem right to charge a friend for labor, although I do expect them to pay for materials. I'm happy to help them out, although I do generally expect them to work alongside me, even if it's just chatting, passing me tools, keeping things organized and bringing me beers. I long ago weeded out most of the people who only came out of the woodwork when they needed a favor.

author: Ed.Kloonk
author_rank: Super Contributor
timestamp: October 06, 2021, 01:10:08 am
content: Some time ago, I found this nonsense stops with a simple "I wont touch it while ever it's got Windows on it."However, I'm sure everyone would like their own personal sys admin.

author: Ground_Loop
author_rank: Frequent Contributor
timestamp: October 06, 2021, 02:17:23 am
content: I ran into this problem often with woodworking. 'Make me one of those' would be closely followed by 'I can buy 5 of those at Walmart or IKEA for the same price.' Now I gracefully say no and change the subject.

author: AndyC_772
author_rank: Super Contributor
timestamp: October 06, 2021, 06:33:53 am
content: Hang on a minute... this Chinese "protection" device draws 80mA from the battery, all the time? And it's meant tostopthe battery going flat?Even 16mA is a lot to waste on standby. You're right that a MOSFET would be the way to go, but if you prefer the idea of a mechanical contact, a latching relay would require zero current to keep it in position. Your PIC can easily generate a short pulse to switch the contact position when the battery voltage crosses threshold.

author: HowdyPartner
author_rank: Newbie
timestamp: October 06, 2021, 08:09:42 am
content: Quote from: AndyC_772 on October 06, 2021, 06:33:53 amI've had a faulty dashcam drawing 80mA at all times. The car wouldn't start after sitting in the garage for a week with that standby consumption.

author: AaronLee
author_rank: Regular Contributor
timestamp: October 06, 2021, 08:20:01 am
content: Quote from: HowdyPartner on October 06, 2021, 08:09:42 amFaulty meaning a bad component, or faulty by design? I have experience in dealing with engineers designing automotive gear, and most of them realize the importance of minimizing current consumption, but it takes a LOT of additional work to do it right, and a lot of them are willing to take shortcuts to meet deadlines. If I was buying something (not just automotive stuff) where current consumption was important, I'd check the device compared to the spec first thing, and return it if it didn't meet spec. I'm willing to bet there's a lot more stuff out there that doesn't meet spec than most people realize.

author: jonovid
author_rank: Super Contributor
timestamp: October 06, 2021, 08:42:14 am
content: IMO if you do not have a spare unit or gadget then and there foran on the spot salethen the answer is No!as saying Yes will cost you time and frustration. people do change his or her minds then google it and find a new toy online.if your in business to sell gadgets of this type then your prepared for on the spot sales wen needed. with a return policy for unwanted merchandise from impulse buying.a true Friend can take aNOfor an answer

author: AndyC_772
author_rank: Super Contributor
timestamp: October 06, 2021, 08:53:06 am
content: They're probably compelled to take short cuts in order to meet cost targets.A lot of my jobs are automotive accessories; I do consulting work for a number of businesses who make and sell products that have a permanent conection directly to a vehicle supply.Because of the quantity and/or price point, they're all highly cost sensitive. Components that don't directly impact the spec sheet or user experience (eg. protection or supply switching) are the first to be questioned. Engineers don't always have the confidence to stand up and insist that they really are essential, even though the customer will complain the moment the device drains their battery or blows up a month after they've installed it otherwise.

author: Wilksey
author_rank: Super Contributor
timestamp: October 06, 2021, 09:31:02 am
content: Yes, 80mA, the one I had to hand was 16mA, I have about 50 of these relays over from another project and just decided to use it, I use my car every day so I am not worried about such a small draw, it has a massive battery and while it is only rated at 95Ah the voltage seems stable, I am going away for a week soon so I will see what it does to the battery whilst I am away.

author: HowdyPartner
author_rank: Newbie
timestamp: October 06, 2021, 10:36:41 am
content: QuoteCan not tell, unfortunately. My guess is that the battery has died and it was trying to charge it up all the time.The point is that 80 mA of standby current is way too much for a car accessory.

author: Wilksey
author_rank: Super Contributor
timestamp: October 06, 2021, 04:56:04 pm
content: I have seen people state that an acceptable overall drain is between 50 - 100mA, but I can do the battery calcs and I guess if the car is not left for too long that will be OK, not something i'd like to "guarantee" though.

author: AndyC_772
author_rank: Super Contributor
timestamp: October 06, 2021, 05:09:48 pm
content: These "people" were not informed, reliable sources. Personally I work to the rule of thumb that no automotive device should draw more than 0.5mA continuously on standby, preferably an order of magnitude less.Remember, this device you've built is supposed topreventyour battery from going flat.

author: james_s
author_rank: Super Contributor
timestamp: October 06, 2021, 05:13:54 pm
content: My car regularly sits parked for a week or more between uses so it would be a problem if something was drawing 50mA. IMO a car needs to be able to sit for at least 3 months without the battery going flat to not be a pain.

author: Wilksey
author_rank: Super Contributor
timestamp: October 07, 2021, 12:19:51 am
content: Perhaps someone should tell the manufacturers, this chap measured a bit higher than 50mA being drawn.

author: PlainName
author_rank: Super Contributor
timestamp: October 10, 2021, 06:55:43 pm
content: QuoteCould've written in two paragraphs what he spent 20 minutes trying to say, and I could have skimmed that in 10 seconds to find the relevant detail. As it is, I gave up after 2:50 (which I will never get back).

author: AaronLee
author_rank: Regular Contributor
timestamp: October 11, 2021, 01:12:07 am
content: Quote from: dunkemhigh on October 10, 2021, 06:55:43 pmThis isn't the Pet-Peeve thread, but that's one of my huge pet-peeves - videos that go on and on in order to tell you something they could have in 1/100th the time. It's one of the main reasons that when searching for information I'll generally first click on links that look like they're text based rather than video based. Good thing I didn't bother to click on the video.

author: Ed.Kloonk
author_rank: Super Contributor
timestamp: October 11, 2021, 02:05:31 am
content: Quote from: AaronLee on October 11, 2021, 01:12:07 amIf the title looks fishy and as murky as they often are, I sometimes head straight for a video's comment section and just read a few posts before starting the vid. The beauty of the youtube algo is the majority of peeps are arguing about the meat of the matter and it's among the top comments. I can't be the only one who does this and I wonder how long until you wont be able to see the comments before you watch the preroll and have had watched a certain amount of video.