Electronic hobbies and discussion

[Blender]

The smallest pad size I've dealt with is:
View attachment 64419

Thank God I don't deal with them all day long or I'd be on a shooting spree!!!

Ah, mils, the worst unit ever.

 

[WileECoyote]

Ah, mils, the worst unit ever.

HAHAHA, yes, I have to agree!!!

I'll try to take a picture of my soldering of that part. Hell maybe I'll just grab a "dead board" and remove/solder in place. Repairs are more typical of OP Amps a bit bigger in pad size, for example.

But when I do have to deal with that small of pad size BEADS OF SWEAT just start pouring!!!

 

[WileECoyote]

God PLEASE TELL ME I'm NOT the ONLY ONE with "parts junk boxes"... one of many of them???!!!

HAHAHA, no ESD worries here obviously???!!!

 

[Itaro]

God PLEASE TELL ME I'm NOT the ONLY ONE with "parts junk boxes"... one of many of them???!!!

HAHAHA, no ESD worries here obviously???!!!
View attachment 65309

I have more crap for you

 

[WileECoyote]

I have more crap for you

HAHAHA, I know...

Don't know if you can tell, but the swelling is still there a little and pretty much all day today was hurting to the point of discomfort, but not as bad as it used to be.


I was told to try "cold packs", but I've tried it already and it actually hurts. I've noticed warm to a little bit hot water actually takes some of the pain away. But cold, F'N HURTS and/or seems to aggravate it.

Finally getting to the point where it is not as bad as it was when I had first told you about it.

I'll stop by as soon as I can.

 

[thezentree]

Buncha fkn nerds in here



Me included. I've got an Octoprint setup currently making some stocking stuffers for some friends at work:



I FINALLY got my printer (mostly stock E3V2) to run TPU fairly well yesterday, so that's cool. Previous prints include a functioning G19 frame and some bench vise press brake tools. Also have an AR LPK on the way, so I'm gonna try a Hoffman lower soon.

I've also have a flightaware ADS-B feeder going, but I'm really just doing that until I figure out a better use for that Pi. I need to learn more programming, but grad school has eaten up most of my free time. I talked my way into being an EE for like 6 months at work (I'm a ME so I have no idea what I'm doing), so hopefully I can learn a thing or two.

I've also got a cheap Android tablet on the way so I can run a mobile SDR setup.

Anyway, cool thread.

 

[Itaro]

 

[Chris In Milwaukee]

Glad this part is done. I’m a little tired of soldering under a f’n magnifier.

 

[WileECoyote]

Glad this part is done. I’m a little tired of soldering under a f’n magnifier.

View attachment 67053View attachment 67054View attachment 67055

HAHAHAHA, now you made DAMN SURE that the correct values are in their respective locations, right???!!! Hate to see such nice work get blown solder pads!!!

 

[Chris In Milwaukee]

OMG, I’m paranoid about that! Those little bastards have nearly zero markings on them. That would suck in the worst way.

What my subjects have seen the past several days… shades of Milton…

 

[Chris In Milwaukee]

God PLEASE TELL ME I'm NOT the ONLY ONE with "parts junk boxes"... one of many of them???!!!

HAHAHA, no ESD worries here obviously???!!!
View attachment 65309

Junk pile?

 

[WileECoyote]

OMG, I’m paranoid about that! Those little bastards have nearly zero markings on them. That would suck in the worst way.

What my subjects have seen the past several days… shades of Milton…

View attachment 67056

Junk pile?

View attachment 67057View attachment 67058

 

[WileECoyote]

Some time down the line, very late next year for $$$ reasons, I plan on building some DIY "tower speaker boxes" for my home stereo receiver.

Going to have 8" sub, 5" mid, and tweeter in a ported custom built "tuned box". Going to use WinISD to design the box.

Anyways, right now, all I'm doing is gathering research and information.

My question(s) though:
1) I'm going to put passive crossovers inside that are 4ohm output to the 4ohm speakers, which is obviously matched and how it should be. My stereo receiver is an old RCA with 8ohm outputs. Does the crossover INPUT have to match the output of the stereo receiver output?

2) I can't find any specs or Googl_e this question as every search just talks about how to match the speakers to the OUTPUT of the amp source or the crossovers?

One of the crossovers is going to be a:
Pyle Driver PDXMR35

Whether I use that crossover or any other crossover, they never give what the INPUT impedance is for the crossovers that would connect to the amp source, in this case, my 50W/ch 8ohm output stereo receiver.

So, to sum up, can I connect my RCA stereo receiver 8ohm output to a crossover INPUT, but again, I can't find what the impedance is for the INPUT of the crossover or any crossover?

I'm assuming it doesn't matter for the INPUT side of the crossover?

Thanks for taking the time to read.

 

[WileECoyote]

If ANYONE can help with my question just above, post# 113, I would REALLY appreciate it!!!

So anyways, setting up my electronics hobby desk setup and I have a, pretty much, very custom setup with one of my older computers.

I haven't "logged in" for a few years due to not having it all setup at my last place I lived.

Anyways, I totally forgot what the Admin Password was for my WinME computer setup?






Again, this particular computer is setup with certain hardware and configurations, for example, my PLD programmer. I know VHDL programming fairly well, but have not done anything for a while and want to practice it. I salvage old circuit boards that have "GAL" chips. The ones I will typically see are the DIP varieties, but at my old job, they were throwing away quad packs and I have quite a few of them and I made an adapter to be able to program them in my PLD programmer.






So getting back to the Admin password ordeal, I was STUCK HARD and trying to remember what it was? I was panicking BAD because setting up all of the hardware I MIGHT not be able to do anymore? Yes, very outdated, but, for example, GAL devices are still widely used... most people just don't realize it. Same goes for "serial ports" and/or RS-232, which is a SUPER simple protocol and it all depends on what the end goal is supposed to be for your target design. Example, you wouldn't use expensive components on something that is just sending simple data and speed isn't necessarily a factor. Again, it all depends on the end goal and just as long as the design does it's intended use.

So anyways, I finally go to Googl_e to see if there is ANY WAY to bypass or if anyone has posted something "hacking wise" to bypass old OS stuff? I go through a few web sites and they are all about Win10 and even Win8, but information for old OS's like WinME was virtually non-existent. I finally find a short simple post and the guy said to just click on "CANCEL"... especially if it is a home setup and likely nothing was set as far as an Admin password.

Sure enough, I click on the "CANCEL" tab and it boots the rest of the way.

JESUS H, I was SO RELIEVED that I never setup a password or I would have been screwed!!!

So now I can practice writing VHDL code, program the chips, and build a circuit to see if the chip/code is working as intended.


Loaded my file I wrote a while back... Then programmed the chip.


"Blank checked" my chip after and even "Verified" the code programmed in the chip for "proper read back".




Now that I have my computer setup back, I can continue practicing and making my projects.

I still have a long way to go to finish all of my connections, but it's finally getting there.


My next task after setting up my electronics desk/hardware is to setup my Microchip PIC setup. Both for my WinME machine as well as my Win10 machine.

Sorry for a long winded post, but I'm guessing I posted due to how relieved I was after figuring out the damn Admin password dilemma!!!

 

[Chris In Milwaukee]

Programming ICs is a way-back machine for me! I used to work for Data I/O who makes engineering programmers similar to your B&K as well as big programmers that go on industrial pick-n-place rigs for programming JIT on the production line. Pretty crazy stuff. That was a looong time ago.

Regarding your audio question, don't sweat the input impedance of the crossover. It's insignificant. The speaker+crossover overall output impedance is of concern, however. I'm sure you know Ohm's Law. It applies to speakers, too (although it's impedance, not resistance, the math still works out). So if your amp is rated at 50W @ 8 ohms as an example, if you drive a 4 ohm load with it, your amp will attempt to deliver twice the current to it (round about 100W with limits). Most amps can handle that, some not. I'd say most amps can easily handle a 4-ohm load if they're rated for 8-ohm speakers. Hardly worth worrying about. It's when you try to drive 2-ohm loads and lower that things can get dicey. So be careful how hard you try to drive it!

If you can find a copy of The Loudspeaker Design Cookbook (came out in the 90s, I think), it's a great resource. There are others out there that I have, but they focus on driver configurations and such for more exotic configurations. Something I mean to dig into in the next couple years.

 

[WileECoyote]

Programming ICs is a way-back machine for me! I used to work for Data I/O who makes engineering programmers similar to your B&K as well as big programmers that go on industrial pick-n-place rigs for programming JIT on the production line. Pretty crazy stuff. That was a looong time ago.

Regarding your audio question, don't sweat the input impedance of the crossover. It's insignificant. The speaker+crossover overall output impedance is of concern, however. I'm sure you know Ohm's Law. It applies to speakers, too (although it's impedance, not resistance, the math still works out). So if your amp is rated at 50W @ 8 ohms as an example, if you drive a 4 ohm load with it, your amp will attempt to deliver twice the current to it (round about 100W with limits). Most amps can handle that, some not. I'd say most amps can easily handle a 4-ohm load if they're rated for 8-ohm speakers. Hardly worth worrying about. It's when you try to drive 2-ohm loads and lower that things can get dicey. So be careful how hard you try to drive it!

If you can find a copy of The Loudspeaker Design Cookbook (came out in the 90s, I think), it's a great resource. There are others out there that I have, but they focus on driver configurations and such for more exotic configurations. Something I mean to dig into in the next couple years.

My floor tower boxes are going to have:
1x tweet
1x mid
1x sub

So the "left channel" of the amp will be connected to, technically, 3x crossovers that are going to be located inside the speaker box.

From each crossover to their respective speaker/driver.

So just like the tower speaker below, that is eventually what mine are going to look like. I do WISH they were Cerwin Vegas though as that would be VERY SWEET!!!


But yeah, the "right channel" of the amp will be the same.

An example of what my stereo receiver "amp" looks like, which is an RCA STA-3850 just like the pictures below.


What the rear input/outputs look like.

 

[Chris In Milwaukee]

Does that thing use discreet output transistors or chip amps? I suspect the wattage on the sticker is absolute max output. It should be satisfactory at reasonable listening levels. Shoot for the most efficient drivers you can find at your price point and have fun!

 

[Stairgod]

My two pennies....
As far as I know crossovers are not designed to change impedance.
They are typically a low pass/high pass deal as far as frequency.y experience with exotic set ups is limited to wiring four 4 ohm subs in series with an amp capable of handling a 1/2 ohm load

 

[WileECoyote]

Does that thing use discreet output transistors or chip amps? I suspect the wattage on the sticker is absolute max output. It should be satisfactory at reasonable listening levels. Shoot for the most efficient drivers you can find at your price point and have fun!

My two pennies....
As far as I know crossovers are not designed to change impedance.
They are typically a low pass/high pass deal as far as frequency.y experience with exotic set ups is limited to wiring four 4 ohm subs in series with an amp capable of handling a 1/2 ohm load

For each left and right output channel (NOTE: just the L-CHB and R-CHB are going to be used), which I believe are considered rear channels. I don't plan on using L-CHA and R-CHA.

The driver (a.k.a. speaker) for each crossover are 4ohm. So the output of each crossover is matched to each driver. I'm just wondering what the input impedance is for each crossover?


I will likely NOT go full volume as that would be a bit scary to do either way.

 

[Chris In Milwaukee]

For each left and right output channel (NOTE: just the L-CHB and R-CHB are going to be used), which I believe are considered rear channels. I don't plan on using L-CHA and R-CHA.

The driver (a.k.a. speaker) for each crossover are 4ohm. So the output of each crossover is matched to each driver. I'm just wondering what the input impedance is for each crossover?
View attachment 80569

I will likely NOT go full volume as that would be a bit scary to do either way.

It’s pretty low and insignificant for your use case. And it’s a moving target anyway since it changes with frequency. If you know your component values and your speakers specs, the software will do much of the work for you.