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On Thursday 02 January 2025 07:30:51 am wn4isx via groups.io wrote:

I'm a sucker for test equipment, more so for good equipment at rock bottom prices.

A friend dropped an inexpensive audio oscillator by for me to check out.
,only%202nd%20harmonic%20is%20visible.)

Some interesting stuff on that web site. It's pretty cool that they're into selling kits, as the outfits that used to ain't doing that any more.

This oscillator has a claimed distortion of 2 parts per million (0.0002%).

I don't see where I would need something like that.

I only have access to test equipment that can measure down to 0.001% and this oscillator's distortion was lost in the noise floor of the test equipment.

The frequency was slightly off, well within specs but 1002.31Hz.

For strictly analog, that ain't too bad.

At $89 this represents an amazing value. Yes you can download their assembly manual and "roll your own" but I doubt you can achieve the performance of this unit.

I looked that over, and some of the other ones.

Part of their magic is their PCB layout and hand selecting the frequency determining devices. It isn't worth my time and energy to try and copy their PCB and locate accurate parts.

I'm well know as a cheapskate and I ordered one.

What are you going to do with it? Me, I'll probably end up rolling my own of various amps and things. I do have an HP audio generator sitting back there that I picked up at a hamfest that needs a little TLC. One of these days...

--
Member of the toughest, meanest, deadliest, most unrelenting -- and
ablest -- form of life in this section of space, ?a critter that can
be killed but can't be tamed. ?--Robert A. Heinlein, "The Puppet Masters"
-
Information is more dangerous than cannon to a society ruled by lies. --James
M Dakin

My first, and last, audio reference involved calibration whilst beating against WWV.

That got real old, real fast, and started making recordings of decades and octaves from the tuner in band hall. Took 45 minutes to warm up, but never more than a fraction of a cent off.

That got old too, so ended up buying audio test CD. Pretty sure was from W5YI.

Rock stable signal out of headphone jack of any *1x* cdplayer in a computer.

Now ? Last time I needed 1K I took an oven heated / gps derived & corrected 10Mhz reference and divided until I got what I wanted. /10, /10, /10, /10.

And if I am in a rush, I will just grab my 1khz tuning fork. Pulling that out after getting stopped and questioning calibration has gotten me out of ALOT of speeding tickets.

Most, if not all, were rightfully deserved.

~SD

On Thursday 02 January 2025 04:40:06 pm wn4isx via groups.io wrote:

Their amplifiers have impressive specs, too bad 40 years of riding a motorcycle and being 73 make HiFi someone ridiculas.

Yeah. I have a stereo, along with an octave-band equalizer, in the other room that I haven't hooked up yet, since I moved over here. Which is something like 4-1/2 years ago? I used to have stuff on all the time, not so much any more. I notice that he talks about some huge capacitor on the output of those amps, which suggests a single-ended power supply. I'd rather go with split supplies and no capacitor. But I'll probably end up DIYing something around some of the LM380 chips I have handy here, if I decide that I need another amp. Maybe use 'em in pairs, so I can have a bridged mode.

As to needing a 1kHz AF oscillator with 0.0002% distortion.....who said I needed it? Like I said, I'm a sucker for test gear. He who dies with the most wins....not sure what we might win but I'm sure it will be impressive. [That was an attempt at humor.]

One would hope.

I just completed a PITA "must do" project. We have 20 feet of water pipe above ground. We meant to use a Ditch Witch to bury it but, well knee surgery in June and August meant "That ain't happening." So I added self regulating heat tape with fiberglass insulation then a vapor barrier.

My brother used one of those when he put his pool in. I have no idea what's involved in operating one.

It was 3 hours of unfun laying on my back installing the heat tape and insulation,the vapor barrier was the hardest part.

I've lived with places that needed that stuff before. I'm not entirely convinced of the reliability of it.

I added a remote reading AC mains current/power meter. It will be interesting to see how the current varies as the temperature drops to Antarctic levels over the next week.

That strikes me as a good thing to have on that setup. Cold weather has already affected my weather station, nothing but dashes on the display in here, it's not getting any signal from the outside part, so it's only displaying the temp and humidity in here, and the data and time. I didn't think that it had been that long ago that we put batteries in that outside unit, and the small solar panel is supposed to take care of most of that end's requirements. Not fun, taking that thing down and getting it in here.

There is a chance we might get ice, which could take down the AC mains. Now that'd be a real PITA.

I had a non-urgent appointment scheduled for Monday, and I've already rescheduled it. We're supposed to get some kind of crap and there's no way that I'll be driving over the mountain with that going on.

--
Member of the toughest, meanest, deadliest, most unrelenting -- and
ablest -- form of life in this section of space, ?a critter that can
be killed but can't be tamed. ?--Robert A. Heinlein, "The Puppet Masters"
-
Information is more dangerous than cannon to a society ruled by lies. --James
M Dakin

On Friday 03 January 2025 07:58:04 am SheldonD via groups.io wrote:

My first, and last, audio reference involved calibration whilst beating against WWV.

That got real old, real fast, and started making recordings of decades and octaves from the tuner in band hall. Took 45 minutes to warm up, but never more than a fraction of a cent off.

That got old too, so ended up buying audio test CD. Pretty sure was from W5YI.

Rock stable signal out of headphone jack of any *1x* cdplayer in a computer.

Now ? Last time I needed 1K I took an oven heated / gps derived & corrected 10Mhz reference and divided until I got what I wanted. /10, /10, /10, /10.

I started to build a board that would give me a bunch of frequencies ilke that, nowhere near as fancy iu the oscillator part, but I never did get enough 7490 chips to finish it. It's probably still around here someplace.

And if I am in a rush, I will just grab my 1khz tuning fork. Pulling that out after getting stopped and questioning calibration has gotten me out of ALOT of speeding tickets.

Heh. The last time I tried to fight one of those the officer showed up with a record of calibration, there wasn't any way to fight that. And it ended up costing me more...

Most, if not all, were rightfully deserved.

The last one I got was several years ago, and I just paid it. These days I tend to take it a lot easier, my vision not being as good as it used to be.

--
Member of the toughest, meanest, deadliest, most unrelenting -- and
ablest -- form of life in this section of space, ?a critter that can
be killed but can't be tamed. ?--Robert A. Heinlein, "The Puppet Masters"
-
Information is more dangerous than cannon to a society ruled by lies. --James
M Dakin

I started to build a board that would give me a bunch of frequencies ilke
that, nowhere near as fancy iu the oscillator part, but I never did get
enough 7490 chips to finish it. It's probably still around here someplace.

I used an FPGA. Discovered could only do decade division, otherwise odd harmonics would be created. Never really had time to investigate.

Heh. The last time I tried to fight one of those the officer showed up with a
record of calibration, there wasn't any way to fight that. And it ended up
costing me more...

I pulled mine when on the roadside. I guess instilling the seed of doubt prior to citation being written is/was more effective than fighting with a prepared and waiting prosecutor in courtroom.

Last speed incident involved me going too slow. Was tail end Charlie on a poker run, caught a light and separated from the M.C. Sheriff deputies claim to impeding flow of traffic was thrown out.

I do try to drive slower now. Partly due to age, partly due to cost of fuel. Mostly due to the current crop of "Ragers" running around now. Literally appear out of nowhere unexpectedly.

~SD