Do It Yourself

Trying to make some DIY USB cable, but I cannot seem to find USB 2.0 type B male plugs anywhere in USA, only some from China on eBay with long shipping estimates. Found some type A plugs on Amazon. For type B, looking for something like these: http://www.ebay.com/itm/170578212079?_trksid=p2060778.m1438.l2649&ssPageName=STRK%3AMEBIDX%3AIT

I want to experiment with making some data only USB cables. Looking at the specs of the bulk USB cable by lcomm it shows 28awg twisted for the data lines. Is it ok to use stranded?

Toying with the idea for my Dynamite. Anyone hear the Goldpoint smd design vs the Dact? How about feel? Just put in a 4-ch Alps blue velvet pot, to replace a cheapo I had. I also put in pre-attenuation resistors cause I had the old pot turned to almost off for the levels to be right. Much better.

This is a very niche topic so if you are not planning to buy or write programs for the Keithley 2015 or 2016 thd or p multi-meters then this post will probably not be interesting to you - especially given their skyrocketing prices on ebay and their age. If you are planning to buy one because it has audio analysis built in then there are a number of limitations and issues you should be aware of before deciding to buy. Some of these limitations effect the accuracy and validity of its calculations and are not documented in the manual, some of the limitations effect usability and some effect it programmatically if you access it through gpib or rs232. If you look on the i…

Any of you ever across this stuff? Discrete opamps and 78xx/79xx Vregs? https://sparkoslabs.com/ Wonder if the regs are any good and how they compare to Amb's o78/o79?

I started to think about upgrading my HT and my new plan is to have an AV processor plus power amp. After searching for a while, I figured that Hypex might be a good choice as a power amp. What would be a good option here? A) 5 X UcD400HG with HxR Softstart module Exodus MCH Power Supply Transformer 115/230V x40V 1KVA 5 X UcD400HG with HxR SMPS1200 Plus of course heatsinks, case and other accessories. My current speakers (Infinity Cascade Model Nine, Three C & Three V) don't need that much power, but you never know when upgradetis hits you and UcD180HG with HxR costs only a bit less. So, what do you think? Should I look for something else or …

Sorry to start a new topic on this, but I thought if I posted it on a previous thread it would get lost. The issue with the original power supply was that it was noisy at times. I had originally measured < 2 mV power supply noise, and 3 - 5 mV noise at the amp outputs. But on re-measuring, the power supply noise was > 5 mV with the amp output noise measuring around 50 mV. In fact, the noise measured before and after the regulator was similar. Thinking the regulator was noisy, it was rebuilt with new devices, without improvement. Since the current source (CCS) in the positive supply line should block noise from the raw positive supply, the likely …

http://cgi.ebay.com/OLD-Fluke-407DR-Plate-Filament-Rack-Tube-Power-Supply_W0QQitemZ160184703511QQihZ006QQcategoryZ58287QQssPageNameZWDVWQQrdZ1QQcmdZViewItem If you have room for this thing...

Any preferrences on these? Biggie.

Looks like a DIY ESL? Best regards Moray James.

with that video of a home made tube going round these days... (and it turns out that guy was someone i worked with back in the midwest hifi days 30 years ago) I figured i would show a picture of a tube i made by hand in 1976 (at zenith) Has a couple of bugs in it. (actually a bug and a butterfly) http://gilmore.chem.northwestern.edu/tube1.jpg http://gilmore.chem.northwestern.edu/tube2.jpg Proving without a doubt that i was nuttier, longer than just about anyone. (made from picture tube necks)

So I hate 99.9% of headsets on the market because the headphone portion is always uncomfortable as all hell, and the ones that aren't uncomfortable are huge HD650 style. So I have an uncomfortable ass folding headset thing from Plantronics and a pair of PortaPros I plan on combining. I've done some work so far but this seems like it will be almost too simple of a mod. The PortaPros have that random screw hole that does nothing on the left side and the Plantronics mic is on the left side of that headset with a pivot point. So far I demolished the Plantronics headset and got the mic out of it unscathed. I took the tiny screw out of the side of the PortaPros …

Uh yeah, so I'm failing pretty hard at figuring out why the right channel doesn't make sound. I checked the DCR from each tab of the dynamic driver (which is hooked up to the electret, yes I did mod them so it's not run through the electret into the dynamic driver anymore) and it measures correctly, around 330 ohms. Measured from driver tab to tip/ring and it measures the same. The hell am I doing wrong here? I resoldered the tabs just to make sure, still to no avail, and it's always the right channel, and not the left.

I'm looking to give my headphone cables a more professional look like this http://redsecta.files.wordpress.com/2012/03/650cable.jpg I want to find splitters like this guy used

I have two OBH-11SE's. One of them is broken -- it's mono; other than that, it sounds fine. I got it used. I suspect the previous owner was messing with it. There appears to be an additional jumper from Q9 to Q11 (similar to the one from Q5 to Q6) -- could this be the cause? Or is it a red herring, some sort of tuning thing? I don't see a stray dollop of solder anywhere, but I could be blind. Does anyone have any ideas? Does anyone have a schematic of the thing? Tell me what to measure and where, and I will.

Anyone have a LM337T they could pop into an envelope and send to me? Hate to place and order for a $.50 part with $10 shipping.

i have the next 3 weeks to kill before school starts again. id like to do something productive with my time. i dont know anything about electronics (well i know a little but assuming that i dont know even that will probably be safer for me). i would like to start working on either an amp or a dac that is fairly easy to build. cost is a slight issue so the whole thing should be less than $100 including tools. i already have a soldering iron but no solder. also, i dont know how to read a schematic, much less know how to plan out the layout of the build, so step by step instructions would be highly appreciated. pictures would go a long way too. lastly, id like to build s…

Finally found a way to get cheap output transformers for my amp after reading this page. All resistors are 1/2W unless otherwise noted, coupling caps should be 250V or better. The power supply capacitors are all 240VAC motor run caps from Aerovox which I scrounged for $5 a pop from the surplus store, and the chokes are also cheap surplus store goodies. You don't have to go nuts on the PSU like I did, I just felt like building an amp with no electrolytic capacitors anywhere in it. The output transformer is actually a 50W toroidal power transformer from Amveco (~$20 each from Digikey). If you have high impedance 'phones or simply listen loud then connect the seco…

For the Carbon I am building, the user would like to be able to bypass the volume pot, but would like it switchable for when the source doesn't have a volume control. I had initially told him no problem, this will be easy. The more I thought about it, I realized it isn't quite as easy as I had surmised. Simply shorting the input to the output (wiper) would still result in potentially bad things depending upon where the pot was in its rotation. Since I had already done the pot adapter boards for the gb awhile ago, I started with one of those for pcb layout (the pot I am going to use is a TKD CP2500 4 channel). My initial thought was to take the pot completely out…

Hey guys, I finally found a good home in a small space for the Moth Cicadas I purchased many moons ago, and the room is conducive enough that I can really notice a bit of variance in the drivers. I have a set of unused spare drivers I'd like to sub in, to see if they are more to my liking. The only trouble is, I have no clue how to remove the old drivers. The cicada enclosure is ported, but the port is too small to fit a hand in, so I can't push the driver out from the back. It fits in the cabinet pretty snugly, so I don't have enough room to fit a spudger in around the edge and pry it up. Furthermore, being paper cones, I run the risk of damaging the old driver is I …

I'm trying to fix my grandma's Westinghouse electric griddle from the 50s. The resistor (at least I think that's what it is) has failed. Unfortunately, whatever insulating material was used to encase it has melted, so there is no way to make out any part value labeling. Is there some general "close enough" value part I can replace it with or is an exact replacement the only way? I know this isn't audio related, but I thought I would try asking here before seeking out a vintage appliance repair forum (which I'm sure exists somewhere).

OK, so I need to replace a resistor on one of my ESL-63s so it matches up with the one Kent repaired. Kent sent me very detailed instructions that I think I'll be able to follow. Basically I have to unsolder a wire, unsolder a resistor, install the new resistor and resolder the wire. The rest is just disassembly that can be done with a screwdriver. My screwdriver skillset is pretty strong so I think I'm OK there. I'm looking for suggestions for a soldering iron. Currently the resistor swap is the only task on my DIY schedule. To be honest I doubt I'll be constructing CMoys anytime soon, but who knows? So I don't need the best iron ever but I want to avoid buying ju…

the output on my Zhaolu is too high. I have had some issues with it in the past, but never that bad. However with my two most recent purchases, a Marantz Sr7001 receiver and a MPX3 SLAM I am running into problems. The Marantz's Peak light shows and the sound gets distorted at times because it can't handle the inputs and I can't turn the volume up past 7 o'clock on my mpx3. I've considered getting some of those RCA adapters to reduce gain by 3db or 6db, but I realize that is not an ideal fix. So does anyone have any experience with the Zhaolu 1.3? Can I change the gain on it?

Hi everyone one year ago I bought two Aikido 24V and two Max Millet boards, I have assembled them with BJT and MOSFET. Great DIY project, great sound, really. The "valve sound" when I was young.... I like very much the Aikido sound with the LM317 buffer (great idea!!!!), this is my preferred headphone amply, and I like too the Millet diamond buffer stage, so why don't create a new headphone amp with the best of both Aikido and Millet? Et voil

I have a pair of 2n5457/5458 JFETs on a small board as part of a bias scheme for a 12AX7. The circuit also has a 9v battery. I cannot get the voltage dialed down, so I checked the JFETs. The resistance from gate to source (and gate to drain) read the same in both directions: roughly 1k ohm. These are dead, aren't they?