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Re: Drafted to helo a friend who designs audio amps
I meant to add, do not carry the AC Mains ground through to the 5V V-/ground! You'll introduce more noise then you'd believe possible.
By wn4isx <wn4isx@...> · #99357 ·
Re: Drafted to helo a friend who designs audio amps
Hafler, an amplifier engineer/manufacturer came up with a very clever and simple test procedure: Divide down the output with two resistors and sum it with the input signal also using two
By Bertho · #99356 ·
Drafted to helo a friend who designs audio amps
I've been dragooned to help a friend I've known since the second grade. Jimmy designs and builds ultra high end audio systems, he builds everything up to the speakers. Recently he's ran into some odd
By wn4isx <wn4isx@...> · #99355 ·
Re: aliexpress freq counters views
Some of these are supposed to have tcxo mine had an unmarked Plain xo. Replacing it with a cheap aliexpress 0.5ppm tcxo made an enormous difference And checked against my gpsdo is rock solid at 10mhz
By David Slipper · #99354 ·
Re: aliexpress freq counters views
I've stayed out of this thread because I post too much. Anyway I tried several of these modules and found them to be useless for any thing resembling precision. I had 3, one in each color, and all
By wn4isx <wn4isx@...> · #99353 ·
Re: aliexpress freq counters views
fwiw,i cut a track and fed the rear of the pcb,ie the vhf+ side of things,this now has its own rf feed,it now reads well on 2m vhf and 70cms uhf.
By paul larner · #99352 ·
Re: my new psu
no selinieum in this just a few diodes.
By paul larner · #99351 ·
Re: my new psu
If the power supply in question has selenium rectifiers they need to be changed. They weren't great to begin with, very high internal impedance, and they don't age well. If the paint protecting the
By wn4isx <wn4isx@...> · #99349 ·
Re: Archival data storage
It will leak eventually, but the drives are hermetically sealed, so the leaks are VERY slow. Donald.
By Donald H Locker · #99348 ·
Re: Archival data storage
I've heard of that. I only hope that I can find out about it before I purchase anything like that. It strikes me as a really bad idea... It doesn't matter what you put it in, helium *will* leak.
By Roy J. Tellason, Sr. · #99347 ·
Re: my new psu
The 5020 is s Zaurie power supply model that was heavily pushed / reviewed in early 1970s. I got mine in 1978, used, from a garage sale. Heavily abused, and if memory serves, used a selenium stack
By SheldonD · #99346 ·
File /counter info..pdf uploaded #file-notice
The following items have been added to the Files area of the [email protected] group. * /counter info..pdf ( /g/electronics101/files/counter%20info..pdf ) *By:* paul larner
By Group Notification <noreply@...> · #99345 ·
Re: aliexpress freq counters views
more info inc schematic uploaded to files section.
By paul larner · #99344 ·
Re: aliexpress freq counters views
Has anyone tried cutting tracks to separate the high and low inputs? This shows a conventional preamplifier for each channel paralleled at the input, each channel using a dual gate MOSFET as a
By paul larner · #99343 ·
Re: my new psu
thanks,it has no valves in it,,so dont know about the 6.3v windings,what is the 5002 you mention?,cheers paul. [email protected]> wrote:
By paul larner · #99342 ·
Re: my new psu
Found your pics in photo section. Labeling on transformer yields 1A across all windings, likely because they are all a common center tap. I would expect the 6.3v winding to be around 3Amps? Is there
By SheldonD · #99341 ·
Re: oscilations in my amplifier ruins my PLL
Oscillations in a closed loop system are almost always caused by excessive loop gain.? Try reducing the gain in your feedback amplifier.? You should also ensure that your system is linear over the
By sdmonaco · #99340 ·
Re: Archival data storage
One trick used in high density hard files is two layers of magnetic media with a thin neutral layer between them, each later is magnetized oppositely which is supposed to element room temperature self
By wn4isx <wn4isx@...> · #99339 ·
Re: Archival data storage
two additional failure modes: 1] Tape as described was the older plastic bases, but in addition there is a failure mode of the tape and hard drives self de-magnetizing due to room temperature thermal
By Charles R Patton · #99338 ·
Re: Archival data storage
One of my wife's cousin is a bean counter. Yea I know the shame of it. She was down to finalize my deceased mother in law's estate. [Don't die, it is a mess] I mentioned storing and backing up data
By wn4isx <wn4isx@...> · #99337 ·