Search found 2683 matches

by haklesup
Thu Nov 15, 2018 4:54 pm
Forum: General Discussion
Topic: Opus BT-C3400 lipo charger / tester
Replies: 1
Views: 24

Re: Opus BT-C3400 lipo charger / tester

I found it in this manual https://images-na.ssl-images-amazon.com/images/I/51TCfcbvBaL.pdf DISPLAY Selection LCD Display Backlight Control. Press and hold the DISPLAY button for more than 5 seconds to toggle the backlight mode. To turn on the LCD Display Backlight press and hold the DISPLAY button f...
by haklesup
Thu Nov 15, 2018 4:49 pm
Forum: General Discussion
Topic: IC compatibility Question
Replies: 2
Views: 14

Re: IC compatibility Question

They have the same logic function but internally they are very different. The HCT part is CMOS and the LS part is Bipolar technology. The input and output logic levels are different. Consult the DC specifications page of the datasheet and look at the VIL, VIH, VOL and VOH levels. In most cases the C...
by haklesup
Fri Nov 09, 2018 11:52 am
Forum: General Discussion
Topic: Microphone in a bubble...
Replies: 7
Views: 158

Re: Microphone in a bubble...

an electret mic is not the highest fidelity options on todays market anyway. Its handy because it can be used with Voltage boas rather than current bias. Most of these could probably be waterproofed by simply putting tape over the sound port and sealing the electrical contacts in epoxy. They may alr...
by haklesup
Fri Nov 09, 2018 11:44 am
Forum: General Discussion
Topic: How select the Commonly Used Electronic Components
Replies: 6
Views: 124

Re: How select the Commonly Used Electronic Components

Capacitors are among the most confusing parts to select because there are many unfamiliar parameters delineating product lines and quality/reliability grades. This as well as similar values and form factors over different construction types (electrolytic vs tantalum for example). Best place to start...
by haklesup
Thu Nov 08, 2018 11:17 am
Forum: General Discussion
Topic: Microphone in a bubble...
Replies: 7
Views: 158

Re: Microphone in a bubble...

All of those materials would impede sound waves and attenuate the sound somewhere along the spectrum. Even considering an idealized flexible membrane, you now have 2 air masses coupling through the membrane with one being much much smaller than the other. Since air on both sides is compressible, no ...
by haklesup
Tue Oct 23, 2018 5:09 pm
Forum: General Discussion
Topic: Lithium Ion charger hack..
Replies: 7
Views: 269

Re: Lithium Ion charger hack..

following the link from the schematic page to the part you do get a reference schematic with the NTC included but you need more than that device, you will need the voltage divider it forms with R1 and R2. the web page says "Thermal feedback regulates the charge current " So I presume the voltage on ...
by haklesup
Mon Oct 22, 2018 5:37 pm
Forum: General Discussion
Topic: Amplifier LM358—classical circuits
Replies: 5
Views: 308

Re: Amplifier LM358—classical circuits

not surprising, some of those circuits are very incomplete. If you are interested, continue studying op amps in general, there will be many many references. Once you understand the basics of applying them as Amplifiers, filters, current sources, comparitors etc then you can start looking at the spec...
by haklesup
Fri Oct 19, 2018 12:00 pm
Forum: General Discussion
Topic: USB-C, 100 watts?
Replies: 2
Views: 214

Re: USB-C, 100 watts?

What I found seems to be mainly press releases some a few years ago This was the most recent citation I could find https://www.pcmag.com/article2/0,2817,2478121,00.asp I'm still looking for an actual technical spec for a cable or connector that says this capability was ever implemented or what it mi...
by haklesup
Fri Oct 12, 2018 4:40 pm
Forum: General Discussion
Topic: How to tell it is good?
Replies: 8
Views: 317

Re: How to tell it is good?

A variable regulator like LM317 will work but it will be inefficient when you run it at low voltage and higher current, that's when you maximize the voltage drop across the device and maximize and so is the power, this is when it will become hottest. The regulator is best used for known loads if bat...
by haklesup
Fri Oct 12, 2018 1:24 pm
Forum: General Discussion
Topic: Spy camera-wireless signal boosting.
Replies: 10
Views: 1458

Re: Spy camera-wireless signal boosting.

If the spot is secure then an IP camera connected to a willing neighbor's Wi-Fi would be simplest and most reliable. If no wi-fi, get a cheap phone and tether to the camera. If not secure, put it all in your car and run it off the battery and park in a strategic spot. A Dash cam might suffice for th...
by haklesup
Tue Aug 28, 2018 12:47 pm
Forum: General Discussion
Topic: i need a long QR type code identified
Replies: 16
Views: 676

Re: i need a long QR type code identified

It likely translates into the same test just above it possibly linking back to an account holder that paid for the postage but I wouldn't expect them to tell you who it is without a warrant.
by haklesup
Mon Aug 27, 2018 11:38 am
Forum: General Discussion
Topic: HDMI Plug\Connector Issues (RANT)...........
Replies: 10
Views: 2262

Re: HDMI Plug\Connector Issues (RANT)...........

sounds like a cold solder joint and working the connector remakes a cold weld for a little while. That's usually what I find when there is finger tip sensitivity to open circuits at a cable connector (where replacing the cable does not seem to help). try a reflow with hot air, water clean flux would...
by haklesup
Tue Aug 21, 2018 3:39 pm
Forum: General Discussion
Topic: Needing ESP8266 help for a wifi clock build.
Replies: 5
Views: 448

Re: Needing ESP8266 help for a wifi clock build.

Looking for info online, I can see modules are either configured in a larger DIP with 30 pins and a smaller board with 8 pin header likely strictly serial. Can I assume you are using the lower pin count version and are planning to interface to a decoder directly using serial methods. I think the hoo...
by haklesup
Mon Aug 20, 2018 1:17 pm
Forum: General Discussion
Topic: TV lacking remote control...
Replies: 5
Views: 405

Re: TV lacking remote control...

"Well, thinking of buying my next TV, plugged back... and it works fine. Now no justification for a new TV :sad: .
Anyway, somehow, Murphy strikes again."

Shoulda started with the reboot, but maybe you want a new TV anyway, the 4K smart ones are reasonably priced now.
by haklesup
Thu Aug 16, 2018 12:03 pm
Forum: General Discussion
Topic: i need a long QR type code identified
Replies: 16
Views: 676

Re: i need a long QR type code identified

I was also able to read a string of nonsense characters probably translated from a binary string but it was all garbage. I couldn't say if that string was correct or scrambled but it was clear one needed the right app with access to the right database. I used the first QR reader app I found in the a...