Salvage yard finds

[Enzo]

Went to the MSU Surplus store this morning, got a nice Triplett 630PL meter for $10. It needs the batteries for the resistance functions, but otherwise seems to work.

Electro-Meters: Triplett 630-PL Series, Analog Multimeters

Got a Heathkit IG-82 for $12.

http://www.nostalgickitscentral.com/.../test/ig82.jpg

[Chuck H]

I have to admit that I would have walked right past that Triplett meter because it looks for all the world like so many cheap meters that go for pittance at your local Rat Shack. The specs show my error. Nice score on both counts.

Chuck

[Enzo]

yeah, a quick look at the picture looks like any cheap analog meter, but the thing is large, the meter face is 5" across, the knob is over 2" long, for scale. It is about the same size as a Simpson 260. it's a real meter, not a toy.

[imaradiostar]

I have a Triplett VTVM and it's amazing. I e-mailed some random fella on the internet and it turns out he's in possession of all the old factory documents from when Triplett got shut down. He was very nice and helpful.

Here's an excerpt:

Bluffton was and still is a small town (in NW Ohio). The Triplett plant hasn't been in operation in over 3 years, and the Triplett family hadn't been with the company since about the mid-1980's. According to my Mom, who turned 96 yrs in August, Ropp Triplett is in his mid-90's and still lives on the S. side of Bluffton. When I was young, growing up on the family farm located one mile NE of Bluffton (on Hancock County Rte 313, which used to be U.S. Route 25 "The Dixie Highway", before I-75 was built), many of my relatives, including my Mom used to work at Triplett. When I was in grade school, during the summer vacations, I used to ride my bicycle to the meter works and spend time with the engineers, as I enjoyed that more than farming. Mr. Ropp Triplett (company president thru the 1960's & early '70's) and his exec. secy. Mr. Norman Edinger (who was also my Sunday School teacher) used to give me blemished or defective testers and meters (ones that were basically good but didn't pass final inspection) to "experiment" with...I still have a few of them in my collection. I haven't lived in Ohio for the past 29 years, and left Bluffton area in 1971. Jewell Instruments, Manchester NH bought Triplett 3 yrs ago, chose to "sever"/lay-off all 650 employees but for one engineer, Mr. Mike Hahn, who works from his home in Lima (he used to commute from Lima to Bluffton each day). Mike is the holder of the Triplett archives and engineering prints; so when folks contact Jewell or the Triplett website email address for Triplett information, it's Mike who actually provides that information. This past summer, Mike gave to me several van-loads of the remaining (new) manuals, "marked-up manuals", advertising prints, factory signs, engineering papers other than the blueprints (the Engineering Change Notices, REA's Request for Engineering Action), as he kept everything he needed and nobody else wanted anything, apparently. Bluffton is a 9 hr. drive from Oswego NY where we live.

You are fortunate to have the AC/RF probe with the original rectifier tube intact. The first thing that usually gets lost is that probe; and it's the most difficult probe to build from scratch. I remember an engineer told me years ago that with those Triplett VTVM's (Models 650, 850, and 631), the tubes were purchased from the GE/KenRad plant located just S. of Bluffton in KY (the plant's number was "188-5"). They used on average about one in five of the tubes delivered, because only that many would "age" and calibrate properly for use in a VTVM.....what I'm saying is that if your original tube is good, be sure to leave it there and use it, as it was aged well and the VTVM's circuits were calibrated to work well with those particular tubes. BTW, if your probe is missing the mating Amphenol microphone screw-on connector, don't buy a Radio Shack version, because these cheap overseas connectors have a "bastard" thread that will thread onto the Triplett's socket, but eventually it will destroy the threads....Mouser and Digikey do sell the real thing, which will have a brand name on it (like Amphenol, Cannon, or WPI). On the cheap Chinese-made fine threads, the problem is not the threads per inch, which is correct....the problem is the actual "pitch" (thread angles and depths) are all wrong.

The original DCV-Ohms probe used a braided, very flexible shielded cable (there are various Belden microphone cables and stranded coax cables that would work); the shield connected to the Neg. banana receptacle, and the signal (+) goes thru the center conductor. The purpose of the 1M resistor in the probe is to help isolate capacitive and inductive interferences or loading between the circuit under test and the VTVM for the DCV ranges which are all at 10MegOhms input or higher. For the Ohms readings, the 1M resistor is switched out and not used. If you don't have that probe, you could easily make your own switchable (or two sets....one straight thru for the Ohms, and one set with the 1M resistor for DCV ranges) probe; or use a switchable probe from any Heathkit or Eico or RCA VTVM, which are easy to find. Yes, without this 1M resistor in the probe, the DCV readings can be off approx 7 to 9 percent. If you were to Google for VTVM probe information for Heathkit, you can also find some so-called short-cuts where you install the 1M resistor physically inside the tester on one of the wafer switches......but this is a very bad idea which completely defeats the purpose of placing the 1MegOhm resistor inside the probe. It's important to have that "isolation" resistor inside the probe....as close as possible to the circuit under test.

It's interesting that during the late 1960's thru about 1983 Triplett also offered their "Solid State" analog VOM's, the portable models 600, 601, 602, and 603 & their "drop-proof" Model 64...and the equivalent bench model 802...the switchable probes for these models contain resistors anywhere from 600 K Ohms up to 1.6 M Ohms, depending on which exact model the probe is designed for. The transistors in those are all FET's of various types.

Fascinating fella! I don't wanna post his email publicly but I'll send it privately if anyone is interested.

jamie

[imaradiostar]

What I meant to say by all that is that's a good find! We have a similar meter at work that we use often because it shows us things that a digital meter can't!

jamie

[Bill Moore]

I don't intend to change the thread, but what do you do when your old meter needs an 8.6V battery?

[imaradiostar]

Use a 9 volt or bunch of AAA or AA cells with a single diode in series to drop the voltage.

jamie

[Enzo]

The meter I found needs not only a 1.5v D cell, but also a 30v cell. I can find the 30v cell for $12 from Mouser or Digikey or one of those. 8.6v sounds like an old mercury cell, is it?

[Bill Moore]

Yeah it is Enzo, I think this was a "kit" meter I built back in the 70's. It too uses a "D" cell. I think the 8.6V is a reference voltage for one of the functions. Some where I have a plan for a 9V and a 1.5V powering a constant voltage regulator. Seems like a lot of trouble! I was hoping someone would make a replacement battery.

[Enzo]

They probably do. You can still find the old 45v and 60v batteries - they look like overgrown 9v batteries. And a lot of other odd ones, like the 30v cell for my meter. But they are not just everywhere. If I wanted something that esoteric, I would look maybe at the Eveready site to try to ident the product, then find out who sells that model battery.

[J M Fahey]

I may be way off, but I *think* mercury cell batteries are actually forbidden, and have been so for a long time.
I'm also a photographer and unfortunately, most "classic" camera built-in meters (impossible to modify) were built and calibrated with mercury batteries, unavailable today. "Correction" as suggested on many Forums (setting ASA sensitivity off a certain amount) does *not* work as intended, because in photo world everything is logarithmic (or exponential) , so "linear" corrections work (sort of) only on a limited range.

[aklooster]

I have a Triplett VTVM and it's amazing. I e-mailed some random fella on the internet and it turns out he's in possession of all the old factory documents from when Triplett got shut down. He was very nice and helpful.

Here's an excerpt:



Fascinating fella! I don't wanna post his email publicly but I'll send it privately if anyone is interested.

jamie

I would appreciate a copy of the full message. I have an interest in vintage electronics. Thanks

[km6xz]

The 630 was the meter you got if you were wealthy, the Simpson 260 was for the rest of us, as I remember it. With all my tons of test gear I doubt I've ever owned Simpson 260.
The first thing you notice about the Triplett is that it is heavy, a couple kgs. And then the deep recessed range switch that had a solid feel and detent.
If you had to reproduce one today, the taut-band movement alone would be worth twice more than such a VOM would be worth considering the number of hand scopemeters out for not much more.
Good find.

There are only a few things I miss by not being back there, the mountains in northern California, the north coast, and the test equipment swap meets. Serious.
There were a lot of test instrument swap meets and fleamarkets in the San Francisco Bay Area, all filled with real bargains and trading potential if you know what to look for and could calibrate the stuff. HP was such an influence in the area that most of the gear traded was lab type H-P and Tektronix, lots of microwave gear and fixtures, logic analyzers ext. I had a old VW van that only existed for transport to and from the two main swap meets each month. When I moved to Russia I gave most of a warehouse full of good calibrated lab quality gear to a friend because he was the only one with a large enough truck...a furniture mover by trade. He sold it all on eBay and bought a house with the proceeds. I doubt if I had more than $25000 invested so the return on investment was pretty good. I kept some and the rest was given to my employees when I gave them the business. From decision to go and actually arriving here was 2.5 weeks. It is not easy to get rid of so much personal property in 2.5 weeks. Kept 1 car, 1 house, and a 10x15 storage unit full of books gold records, photos etc. I did keep a Tektronix 570 Tube curve tracer however;>) Also kept a Fairchild curve tracer that works on semiconductor and tubes, with collector/plate sweeps to 1kv.

[Enzo]

When I was a kid in the 1950s learning electronics, that was still the post-WW2 era, and the Korean War was still hot. The military was upgrading things a mile a minute as well as decomissioning things. All of which is to say there was a heavy surplus equipment market, very different from today. Most surplus today seems to be components. So finding a whole functioning piece like that is a treat.

In all my years, I never owned a Simpson 260 either.

And you are right, that Triplett does weigh two or three times what it looks like it will.

[km6xz]

The 50's was a pretty good time to grow up in the US, the between wars time was one of dramatic growth and optimism.
A good portion of the surplus equipment from WWII was dumped into the ocean but what made it back to the states was sold to scrap brokers for cents per pound. Not many electronics or radio hobbyists did not have a few ARC-5 command sets or a ART-13, BC-348 etc. The prices were the same for a great piece of gear as if it was the same weight in garbage. Command transmitters or receivers were $2-5 on the retail market so the brokers who sold to the surplus stores must have gotten them for $0.20 each.
When the USSR launched Sputnik all changed for electronics buffs, particularly kids. There was a tremendous emphasis on math and science in grade and high schools. The federal government donated a great deal of gear to equip hobby shops and electronics classes, and Hammarlund, Johnson, and Hy-Gain won contracts to supply supply every high school with a quality ham radio station. That was a real kick start of a second wave of growth and the US becoming a major player in high tech. Unfortunately, the bright kids today are funneled into business/finance instead of science and engineering. Most careers paid about the same so the choice a kid made for his life's work was based on passion instead of solely on income as today. I think the first time I thought about money in connection to work was when a royalty check came for a project that I would have done for free, in a greater amount than I had ever seen before.
There is still a large surplus industry in equipment but there are hundreds of brokers with inside connections that get all the valuable equipment which goes to equipment sales and rental companies. A few areas of the country still have backdoor access such as I described about the Silicon Valley test instrument swap sub-culture. By far the majority of surplus that is available retail is industrial surplus which is primarily components and sub assemblies for products that ended production or companies closing, etc. Another factor in seeing less good RF and test instruments is that there is a lot less general purpose instruments being made now. Even the kings in that field, H-P/Aligent and Tektronix are mere shadows of their volume and dominance of 20 years ago. Tek has fallen on hard times and Aligent sales are way down. There are not as many techs used in industry so fewer workbenches to fill with gear. It is cheaper to replace gear in the field than fix it, and what does need work often gets shipped back to the countries that made it if it is a valuable piece. The test instrument industry in China is booming, since they have more techs and engineers than anyone. Each year they graduate more engineers than exist in total in the US or in Europe.
I still love old test and radio gear, it is what I grew up with and I'm happy keeping in it good working condition for decades. My first scope, was a Tek 503 and second was a 545B that I still had in storage, in perfect condition 40 years after I got it. It was not used much for the last 10 years before I gave it away but it got calibrated and aligned every year. It still had 90% original tubes from when it was made. Still, it is a perfect scope for a hobbyist working with tubes because you could accidentally draw an arc with a probe with any scope, due to a parasitic oscillation created by the drawing away of the Hi-Z probe. That kills solid state meters and scopes. Doesn't not cause any concern with an old tube scope.
But I like new tech also, love working with surface mount....a whole lab of spare parts can fit in a pocket. Many of the cheapest monolithic amps work and sound better than anything available in the "golden days".