Avometer model 40
 

Hi I was out for my once a day exercise and came across a avometer model 40 I dont no anything about these I checked the batteries and changed the 1.5 aa then checked the voltage of a battery and a resistor on the meter seemed to work

I know nothing about them or how to use one. Would anyone have a manual for it so I can find out more and learn how to use it properly and find out about the q

Mark

Re: Avometer model 40
 

You may find images if you search on here; many of the manuals have been scanned on by forum users.

If not send me a private message and i will email images to you at the weekend.

The critical thing is to pay full attention when using the meter as (despite the cut-out) they are vulnerable to overload, reverse polarity mistakes, and impact. The voltage ranges on a Model 40 are less than ideal by the standards of today, but they can be surprisingly accurate.

Dave

Re: Avometer model 40
 

Useful info here http://www.richardsradios.co.uk/avo40.html and here https://www.vintage-radio.net/forum/...ead.php?t=2804
and use the instructions for a Model 7 which will be a good guide.

Re: Avometer model 40
 

Hi,

Model 40 Mk II working instructions attached.

Operation would be pretty much the same for the Mk I.

Ian

Re: Avometer model 40
 

Thanks for that Ian I will print it and have a good read

Re: Avometer model 40
 

Reading the manual And what buttons do.
The ÷2 button doesn't move, should it be like a button or would it be stuck

Mark

Re: Avometer model 40
 

It's mildly spring loaded so, yes, it should move in for low V/A ranges and spring back out for high V/A ranges. (ie it doesn't rotate)

Re: Avometer model 40
 

Ok so maybe mines stuck in then thank

Re: Avometer model 40
 

I have now had a better look at it I have taken it apart to see if I could ease the ÷ button in and out to see if it would work the date inside says 1969 so I would presume that that was its last calibration there is a date for 68 as well. After taking it from its case I noticed that the P adjuster has a crack so when you turn it the brass bit doesn't stay straight that explains why at different point it would shoot to 0 still it was free maybe in the future I will look for another one

Thanks for the help
Mark

Re: Avometer model 40
 

A very small amount of 3 in 1 can ease the button where bakelite rubs against bakelite. It's feasible that a piece of grit might have jammed it, it is inaccessible from behind until the meter movement is removed- (a search on the forum will produce precautions/instructions for this.)