using a fluke 83

[m3vuv]

Hi all,i need to take some measurements on a cct that calls for a voltmeter with at least 10mohms per volt,can i use a fluke 83v for this,if not an avometer 8mk2,tia.

[bdunham7]

10mohms per volt

That sounds like an ammeter to me! 

I don't kvetch over minor typos or deliberately misconstrue every small imprecision of grammar or terminology, but I really can't understand any of what you are saying here. 

The Fluke 83 should have an input impedance of about (but not precisely) 10⁷ ohms, or 10 Megohms, or 10M for short.  So ohms-per-volt depends on range.

[Benta]

The Fluke 83 should have an input impedance of about (but not precisely) 10⁷ ohms, or 10 Megohms, or 10M for short.  So ohms-per-volt depends on range.

Nope, that was in the good old days with AVO-meters. Modern DMMs have the same input resistance regardless of range. Here, as you say, 10 Mohms.

[m3vuv]

should of said megga ohms,its to take readings on a bradley ct417c  that i am trying to repair,its from 1965,in the service manual it calls for a valve voltmeter of at least 10 megga ohms per volt,so as not to load it i pressume.?

[bdunham7]

Modern DMMs have the same input resistance regardless of range.

True, the ohms part doesn't change.  But as the voltage range changes, so does the expression ohms/volt.  Although you typically wouldn't use that expression to describe a modern DMM, the 1000V range is actually 10,000 ohms per volt, and so on.  So when you compare an old analog meter to a modern DMM in an application where this might matter, you have to consider the issue.

[bdunham7]

should of said megga ohms,its to take readings on a bradley ct417c  that i am trying to repair,its from 1965,in the service manual it calls for a valve voltmeter of at least 10 megga ohms per volt,so as not to load it i pressume.?

Better check those specs, that doesn't sound right at all, especially the Avometer you mentioned.  A VTVM might be something like 11 Megohms, but not ohms per volt.