Del spends a crapload of money......on old test equipment

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67Dart273

67Dart273

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Many of you know I screw with old outboards. One thing that you need is a high voltage leakage test as well as capacitance test for the condensers, and a way to test coils. When I first saw this girl I thought it was REALLY old......like vacuum tubes.......like the '50.s But it actually contains some IC's and transistors. From the "somewhere in the 80's" Military. Built like the proverbial brick outhouse. We'll see, I guess. Another 50 bucks for shipping

The military manual for it if you care about such things

https://www.liberatedmanuals.com/TM-9-4910-736-14-and-P.pdf

This can measure coil resistance which is a minor thing......any multimeter can do that

It can measure "condenser" (capacitor) value, and that is fairly minor, as you can now buy inexpensive meters to measure that

But what is a bit hard to come by is a repeatable standard to measure capacitor leakage at high voltage

And it has variable current to an ignition coil under test, and can measure the output voltage. This way, you can line up a bunch of (say, outboard magneto) coils and compare them for current in vs voltage out, and high voltage leakage.

I just hope the damn thing works

Screenshot at 2020-07-12 16-46-48cs.jpg


coils-l1600cs.jpg


3s-l1600cs.jpg
 
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Wow that looks like a really interesting piece of equipment.
 
That's a pretty good score. Somebody really dug deep for that one.

The shop I worked in, we always had the new guy test the condensors by holding onto the lead and pulling the starter cord. Worked everytime!
 
You don't know what to get into next. lol and money burning a hole in your pocket. lol
 
If it doesn't work, it won't be hard to repair (especially since you have the tech manual with schematics) :)
I too have a weakness for "vintage" but functional equipment. This is just one corner of one of two "play rooms"!
(At one point I had 14 Tektronix scopes alone...now down to about 8 or 10) :D
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^^A boy can never have enough WWII Command sets^^ I don't have any ARC-5 transmitters, anymore, but I do have one of the LF receivers, up through 500khz? Don't remember.
 
Im looking for a '78 era "AF oscillator" and "attenuator" to align good cassette decks. Needs to read db also.....from 1978 Sony repair manual Maybe just a laptop and a small amp?

AFosc.jpg
 
Is the 333hz and 10khz at 25mv all you need? In other words you don't need a wide range?

If so you might make that work. You would need something of accuracy to measure the output level. None of my Flukes for example go to 10khz. I have one that "I think" goes to 6khz I used to use it in the field to equalize rented dry copper pairs to the radio sites. These of course are speech quality pairs so they don't need as wide range response

If you have a decent oscilloscope that would work for level. Google egag for step attenuator. Actually you can make one for audio. What kind of steps do you need?

You can build them with slide switches
 
Years ago I "restored" an old 5-tube tabletop radio. I ended up replacing all the capacitors. I didn't have any good way of testing them, so I replaced them all. Ever since then, every time I look at anything electronic that's more than about 20 years old, I mentally figure the hassle to re-cap and usually get cold feet. My brother has an original Fender Bassman amp that could really use a good going through. It's on the "someday" list.
 
All depends on the quality of the original components, and how the equipment has been used (hours, ambient temp, etc.)... I've got Command Set receivers from WWII that still use their original caps. Lots of Tek and HP gear from the 60's, only two bad filter caps in the last 20 years.
Those 5-tube radios had lots of hours and definitely were not designed to Tek/HP/General Radio standards ;)
 
Here's a cap story you can appreciate. Years and years ago I made a deal on an ill Heathkit SB220 needed power supply work and caps, may have needed rectifiers I don't remember. Anyway one late-long-weekend-three-four-day-weekend, I just HAD to. Went down to the 'junkbox.' Came up with a pair of old military oil filled caps that would actually fit in the confines of the old filter bank enclosure. You have to have two matched caps because it's a voltage doubler. I KNEW they were low on value, but just "hoped." I don't remember anymore, they were either 8 mikes or 4 mikes apiece, so half that in series.


Anyway put them in it seemed to work fine and ran the amplifier that way for months. Then I got "a deal" someone wanted the thing worse'n I, and I agreed to install the proper caps. Bear in mind this ran some 3200 volts or so on the plates. (3-500Z's a pair). When I pulled those old military cans out, I discovered THEY WERE 600 VOLTS EACH. So 1200V working voltage operating on over 3KV!!!!!

The little box with the big red sign is where the diode rectifiers and caps go

sb220_inside_1.jpg
 
DrCharles said:
Those 5-tube radios had lots of hours and definitely were not designed to Tek/HP/General Radio standards ;)
Click to expand...

Worse is "alleged ham gear" like the Hallicrafters S-38 series. They were AC/DC "series wired" transformerless sets, with a METAL case, sold as "ham receivers" where the company should have known that young, inexperienced kids were going to hook them up with other equipment.........their novice transmitters. VERY dangerous
 
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