Search found 2664 matches

by haklesup
Tue Jul 10, 2018 2:11 pm
Forum: General Discussion
Topic: Line Array - Anyone have experience?
Replies: 5
Views: 82

Re: Line Array - Anyone have experience?

Interesting but I don't get why. Does it have a special sound quality? I can see if you drove each one separately with some kind of DSP you could probably do some interesting stuff but if all driven from the same source, in phase I wonder how it's sound differs from a typical enclosure with similar ...
by haklesup
Tue Jun 26, 2018 9:45 am
Forum: General Discussion
Topic: Experimenting with Hot Glue..
Replies: 101
Views: 10371

Re: Experimenting with Hot Glue..

I wonder if the Silicone II would have worked better. In any case, there are spray on Silicone conformal coating products if you really needed that kind of protection. In most cases a urethane conformal coat is sufficient and is removable with acetone. Most modern parts can survive acetone but I wou...
by haklesup
Thu Jun 21, 2018 11:19 am
Forum: General Discussion
Topic: To evaluate performance of used 18650 cells...
Replies: 22
Views: 1160

Re: To evaluate performance of used 18650 cells...

If you can find a clock that you can start and stop with a control line, then it would not be too hard to make a 0.9V level detector with an op amp and stop the clock when the threshold is reached. Some MultiMeters had DataAcquisition ports and software, you can use like a datalogger. this was the c...
by haklesup
Mon Jun 18, 2018 2:30 pm
Forum: General Discussion
Topic: To evaluate performance of used 18650 cells...
Replies: 22
Views: 1160

Re: To evaluate performance of used 18650 cells...

I noticed that Max discharge current is the other primary specification used for selection. Naturally you would want a high discharge current for say a super flashlight but lower discharge and a little more capacity for something like a low power toy. How do you suppose one would measure that spec. ...
by haklesup
Mon Jun 18, 2018 12:15 pm
Forum: General Discussion
Topic: What to do with Heathkit stuff?
Replies: 1
Views: 290

Re: What to do with Heathkit stuff?

Unless you are an Analog purest I think the Tubes should be ignored though it does give insight into how bipolar transistors work. As for the heathkit stuff, they are probably quite old and built with average quality components from the 60 to the 80s so they are probably going to have poor tolerance...
by haklesup
Fri Jun 08, 2018 10:14 am
Forum: General Discussion
Topic: Dell laptop battery question
Replies: 11
Views: 739

Re: Dell laptop battery question

by way of example, here is an article comparing 2 18650 batteries from the same manufacturer. Initially you can see one has higher max discharge current and the other has a little more capacity but in the discharge tests, they are very similar. Differences between brands I expect would be greater. I...
by haklesup
Tue Jun 05, 2018 4:15 pm
Forum: General Discussion
Topic: Dell laptop battery question
Replies: 11
Views: 739

Re: Dell laptop battery question

not all 18650 are equal, you could just have some with heavier walled cases and better discharge specs and other minor construction differences.
by haklesup
Mon Jun 04, 2018 4:24 pm
Forum: General Discussion
Topic: I need some wireless help and or advice.. lemme preach on...
Replies: 2
Views: 424

Re: I need some wireless help and or advice.. lemme preach o

what speed, 2400 only or also 5Ghz? This one looks easy to install and configure there is also an N300 version that's a little cheaper https://www.amazon.com/Thinkmart-Wireless-Repeater-Directional-Antennas/dp/B071RDTYMN/ref=sr_1_10?ie=UTF8&qid=1528156591&sr=8-10&keywords=wifi+extender+outdoor Or ma...
by haklesup
Mon Jun 04, 2018 4:00 pm
Forum: General Discussion
Topic: Dell laptop battery question
Replies: 11
Views: 739

Re: Dell laptop battery question

is there a voltage spec on the laptop itself. In any case the lower voltage should mean less voltage dropped across the internal regulators and it should run cooler and more efficiently. The new battery may have a better buck/boost regulator allowing for a flatter discharge curve rather than a gradu...
by haklesup
Tue May 08, 2018 3:55 pm
Forum: General Discussion
Topic: To evaluate performance of used 18650 cells...
Replies: 22
Views: 1160

Re: To evaluate performance of used 18650 cells...

Looks like a nice inexpensive process. Capacity is not the only measurable parameter but it is a good catch all. Can you list the steps to your procedure?
by haklesup
Tue May 08, 2018 1:34 pm
Forum: General Discussion
Topic: Typical 0.1 μF bypass capacitor value...
Replies: 4
Views: 524

Re: Typical 0.1 μF bypass capacitor value...

for most digital circuits the smaller ceramic caps go as close to each IC power pin as possible and shunt higher frequency transients generated inside the IC from getting onto the power lines. Additional larger Electrolytic caps will go at the edge of the PCB where the power supply enters to shunt l...
by haklesup
Tue May 01, 2018 11:30 am
Forum: General Discussion
Topic: A Simple but Accurate Constant Current Source
Replies: 13
Views: 1007

Re: A Simple but Accurate Constant Current Source

Have you checked the accuracy over a range of temperature? 1% is about as good as one could expect with resistors, its probably closer to 3% when you check it over a wide operating temp range but still very useful. Did you use precision resistors?
by haklesup
Tue Apr 24, 2018 12:42 pm
Forum: General Discussion
Topic: Detecting a magnet... from a distance.
Replies: 23
Views: 2515

Re: Detecting a magnet... from a distance.

your signal is diminishing as the cube of the distance while your detector is gaining in sensitivity linearly with the number or turns. I'm impressed you go to this distance but incrementally increasing the distance will quickly result in a coil so big you couldn't lift or afford it. additional loss...
by haklesup
Mon Apr 23, 2018 6:30 pm
Forum: General Discussion
Topic: Aftermaster
Replies: 5
Views: 605

Re: Aftermaster

if you are a consumer and want to be heard by a manufacturer, these days twitter and Facebook posts have a good chance of being seen. However if you want acknowledgement and recognition of a particular idea, that's not likely to happen, the research goes on in high quantity and a single voice will r...
by haklesup
Mon Apr 23, 2018 12:39 pm
Forum: General Discussion
Topic: Aftermaster
Replies: 5
Views: 605

Re: Aftermaster

A lot of newer TVs especially higher end already have the auto volume leveling but dialog enhancing seems like a hearing aid trick and could be useful to those without flat hearing response which is just about every adult. seems a little expensive but not too much so if you need it. These features c...