A.W SPERRY V.O.M

[nomad 11]

i have an older for those of you that dont know what a v.o.m is ? its referred to as a volt ohmeter and is also used to check amps. but amperage isnt involved with metal detectors. if i could figure how to do it ? i'd have the best kick axx metal detector ever. but i can dream. anyway my meter reads approximately 3 volts higher than it should. can this be recalibrated ? its a good meter and i cant see buying another one when i have money into this one allready ? right ? opinions expected.

 

Amazon Forum Fav 👍

Family Maps of Hinds County, Mississippi, Deluxe Edition - Grab it through Amazon!

[ticndig]

I had one of those back in the 80's . at that time you could send it in for repairs and calibrations and may still be able to .
I would not work on it unless you know what you're doing .
If you get it wrong you could end up dead wrong .

often power coming in from the grid is not clean and may vary somewhat in the voltage supplied so your reading could be right.

 

[nomad 11]

no reading is not right. checked against another source.

 

[nomad 11]

only one reply ? i guess this was a hard question. a very useful tool if you're trying to figure out an electrical problem.

 

[pulltabfelix]

Some of the older VOM's had a plastic screw on the dial to adjust it. also google the make and model and the words manual and you might just be able to find the manual online in .pdf format to print out.

About 15 years ago I decided to repair old five tube radios and short wave radios. Found out that I have to buy old test equipment to do it properly. VOM, capicator checker, tube checker and an isolating transformer to keep myself from getting a lethal shock from working on old receivers that had hot chassis. Was lot of fun for two years, but barely broke even from a profit stand point.

with old 5 tube radios which accounted for 98% of the old table top radios, all you had to do was replace all the capacitors and it would then work fine. Rarely was a tube problem.

 

[Professor of Engineering]

Hello Nomad11,

Found this site, perhaps they can help you: AW Sperry Calibration Service

Regards,

Doc

 

[hvacker]

What does a VOM have to do with metal detecting? The only output voltage is in the Ohm's range and that is very low.
If yours has a battery, that's the power used to read resistance (Ohms) and that's all the output power there is.
There are DIY designs for detectors on line. In most cases, manufacturers can make stuff cheaper than we can.

 

[Paleo_joe]

The meter may not be 3 volts high, what you’re measuring may be 3 volts low