Simpson 260 VOM Troubleshoot And Repair - Part 1

[@uni-byte]

Thanks for trying to get this meter working again. They are quality instruments and they still have applications today that cannot be handled with DMMs

[@RPike-bq3xm]

Any examples?

[@uni-byte]

@@RPike-bq3xm Yes, zero EMI emission environments. One in particular I know of was a physics lab conducting experiments to measure the EM emissions from various materials under various conditions. The detection system needed to be calibrated using equipment that had zero EMI emissions, for obvious reasons.

[@migsvensurfing6310]

Obviously you don't have much experience in electronics because then you would not ask.

[@robbo6460]

Excellent work. I really enjoyed the part where you traced out the path on the schematic. The switches always confused me. I’d love to see more. I’m working on a Simpson 160 and it’s making me nuts lol

[@EriksElectronicsWorkbench]

Thank you, I'm glad to know you enjoyed the video. Best of luck on your 160!

[@levent8208]

This is a classic, they were everywhere !

[@ac4nl]

Excellent meter. Still made. I use one all the time. Makes you understand what you're attempting to measure. If you purchase new in 2024 between 550-750 dollars.

[@levent8208]

Wow, I didn't know that, I found a place where they sell it (ITM) probably made in China ? same quality ? is there a market for that ? I have an old Simpson 303-Xl, still working, I love it.

[@ac4nl]

@@levent8208 They are Made in USA. Still a market for them. Several areas still use them. A couple are power monitoring and in EMI free testing environments.

[@RPike-bq3xm]

I love these meters too. I was taught on the Simpson but in less than a years time Fluke came out with the 8060A(B) and the company went with that for any new purchases. Reading any common return AC on Airliners made them wig out. For some reason, I don't have that issue anymore.

[@chuckholland6349]

Great instructions. My 260 has a different problem and I'm hoping someone can help. When switched to either +DC, -DC or AC, the meter pegs on any voltage range selection. Still set at AC or +/-DC and move to any R setting, it stays pegged. Move to 1mA setting, meter reads 5.5 on the DC scale. Move to 10 or 100 mA and meter floats down to around .8 on the DC scale. Only visible problem I see is corrosion on the D battery -, and smaller black wire disconnected. I'll repair corrosion/wire but think D (and 9V) batts only used for R measure so not relevant to the issue. My meter has some different arrangements and markings on the panel - "Output" is labeled "+1V on mine, and AC and DC lead ports are different - mine shows "OUTPUT" left side with a 350 max VDC rating, right port AC/DC 1000V. Another diff is there's an OFF select on the far left of the AC/DC selector switch. Only manual I've found so far is one that matches your unit.

[@EriksElectronicsWorkbench]

I think you have the series 8 model. www.simpson260.com/260-8/simpson_260-8.htm For the problem of the meter pegging full scale on so many ranges I'd start by looking at the shunt resistors across the meter movement. If the resistors are open or out of calibration the meter will have too much current through it and read full scale. This page has all the 260 models listed and links to manuals www.simpson260.com/downloads/downloads.htm

[@billtreadwell8890]

I worked for Simpson in the late 60's at their facility in Elgin, Illinois. I also met my first wife there. I have a 260 series 5. The only problem is that I can't get the needle to zero out on the Rx1 setting. I would take it back to have it calibrated, but they are gone. I am going to try and locate another location.

[@EriksElectronicsWorkbench]

On the series 5 it could be R1, R3, or R16 that is out of spec. Or something wrong with the switch contacts in the Rx1 position.

[@waynegram8907]

ERIK'S, Any examples of what a Simpson 260 analog meter can measure what types of signals that a modern DVM can't do?

[@EriksElectronicsWorkbench]

Analog meters are very good for signals that are changing in value that cause digital meters to display jumping numbers that are hard to visually track. Examples are peaking a tuning coil, measuring a voltage (or resistance) on a potentiometer as it is rotated, measuring a sensor signal as it varies. Yes there are modern DMM's that can plot and track such signals but the simplicity of the analog meter has its place. Also there is no battery required for the 260 to measure voltage or current so dependability factors in.

[@waynegram8907]

@@EriksElectronicsWorkbench When is the TECH looking for when peak tuning a coil or sensors signals? looking for resistance jumps spikes, dead spots, profile taper curves, what else?

[@EriksElectronicsWorkbench]

@@waynegram8907 typically when doing an RF alignment you are looking for a peak in signal level and it is very easy to see when that peak occurs with an analog meter. Sensor signals could be trending up or down and visually easy to see on the analog scale. If you ever do a tape head alignment an analog meter will show you the peak in settings easily. Yes all the things you mention for the potentiometer readings. Recently I was measuring DC current on the microamp scale for a circuit I was testing and found the current was pulsing slightly (and unexpectedly) by just a few times the width of the needle pointer on the 260 meter and I had missed that fluctuation by the readings on the digital meter.

[@waynegram8907]

@@EriksElectronicsWorkbench When measuring DC voltages with an Analog meter and the DC Measurement is Fluctuating/pulsing slightly, What can cause this slight fluctuating DC on the DC power rails?

[@waynegram8907]

@@EriksElectronicsWorkbench Analog meters have a LOW impedance and some DVM meters have a Lo impedance option. Its used for measuring "ghost voltages" but what circuits applications which have ghost voltages? any other reasons of using the Low Impedance meters to measure what types of signals, any examples you can think of?

[@doogsm6013]

I'm a little late but I believe you can order parts for any Simpson meter directly from the manufacturer (Simpson) or you could try one of their service centres. I own a Series 6 and have a Series 3 on the way and a Series 4 I need to pick up from my brother in-law, which is the very unit I used back in the Seventies when I was apprenticing as a Pipe Organ Builder with F.W. Knapton and Son (his father.} I also have a Model 10 which is a 3 range AC meter only (150, 300, 600 ) I am hoping to get the full series for my collection eventually. I also have my eye on some Avometers which are the British equivalent .both brands were also manufactured in Canada just to make the collecting even more expensive 🤥They are both great meters and should be on every Techs bench.

[@EriksElectronicsWorkbench]

Some new parts are available for the older models but generally not the resistors since they are an obsolete type not used in the newer versions. Check out part 2 to see how the repair turned out. Nice collection, you can't have too many meters :)

[@doogsm6013]

@@EriksElectronicsWorkbench Thanks for the heads up on the parts and I'll check out part 2 for sure. Unfortunately that's just part of the collection. If I include handhelds and bench meters I think I'm at +/- 20 meters or so, I might have a problem!. LOL.

[@ivolol]

330+470 also conveniently adds up to exactly 800. I'd guess most of the resistors have aged up slightly over time, I'd look at ordering new ones (R10, R12, R14, R15) for the next time you need to make a buy from a supplier.

[@garywilliam5203]

I have one of these meters from the 60's still in the box. Where can I find batteries for it?

[@EriksElectronicsWorkbench]

This series 4 version and other earlier version models used a standard D cell and four AA's. Later models starting at series 6 and newer used a D cell and 9volt battery.

[@RetroCaptain]

​@@EriksElectronicsWorkbenchI had one for years with the 4 AA cells and D but due to a fall it suffered it wasn't reliable anymore. I bought one that the man said was from the 1960s and it takes either a 22v or 15v battery I forgot exactly what because it was removed (and both the 15 and 22 were very close in size). The slot the higher voltage battery sits in looks like a CR17345 would fit (but not work of course) I'm positive they're still available.

[@EriksElectronicsWorkbench]

@@RetroCaptain None of the Simpson 260 series used the hard to find higher voltage batteries. If your meter uses those batteries it is a different model. The very first 260 from the 1930's used two "905" 3 volt batteries and one "C" cell 1.5 volt. 260-series 2 up to modern series 8 used combinations AA, D, and in newer models a 9volt battery.

[@RetroCaptain]

@@EriksElectronicsWorkbench It says Simpson Canada "260SP" It has a white Reset button on the front The slot for the oddball battery the contacts are top and bottom and it's too shallow for an 006P type to drop down in. Oh it's possible there's a 9v with top and bottom contact...I know I had something decades ago with a very similar battery. I also have a Triplett USA model 630 type 2 and it also has this same size slot battery missing and I'm positive I read somewhere it's supposed to be 15v and someone taped together a stack of LR44 .. probably not Cells but batteries that dimension and managed to supplant the original No. battery. The Triplett lacks the Current range I was after. I mainly used the 10a option on the 260 at my old job this Triplett 630 only has 60uA. Worst case scenario I can swap out the D'arsonval movement from this to the one that is damaged as it still works apart from having to tap it repeatedly to get a reading (that may still be out). This one has I think 2 capacitors that will be out of tolerance. I forgot I also have a Simpson Canada small Ammeter. Micro Ampere Miliampere and Simpson Element Tester for testing the accuracy of Baking Elements and Firing Rods.

[@EriksElectronicsWorkbench]

@@RetroCaptain ok makes sense the 260SP is a different series than the 260 model in my video. The 260SP is the industrial safety version with overload protection. The reset button is part of the overload protection. The 260SP is still manufactured today although batteries used are modern types.