Avo 8

To be honest I still use an Analogue meter wherever I can, my favourite being the 8. But I still love the TMK 500 / 700 as well, maybe it's an age thing

Andy

Aye... There's medical term for it, it's called "Age Related Technological Degeneration"..

Marion

Having had bad experiences with digital meters in the past I still use an Avo 8 for current measurements. They seem to withstand accidental abuse much better.

Al

I use the AVO for anything over 400V. HT on 6146 anodes isn't kind to cheap DMMs. But for normal use I have a pair of decent DMMs. The AVO takes too much bench space and awkward for Ohms. I must get a higher impedance meter though as 10 M Ohm is too low for some measurements.

I was originally trained to use an analogue meter (AVO 8), as that is what the older engineers (who trained me) used.

But I mainly use a digital MM, Fluke 87 and an el cheapo hand held analogue for electrical work, and a Fluke 79 and el cheapo analogue for electronic work, and sometimes a mix of all three!

The analogue meter still has it's uses, the lower impedance also has it's own benefits too especially in general electrical work where 'phantom' stray pick-up of voltages from adjacent or multi-core cables renders the digital meter confusing.

Also in electronics there are tricks that you can do with an analogue meter that is very difficult or impossible to do with a digital meter.

Sometimes the speed of the 'kick' of the needle is of more use than an absolute reading (even the Fluke 87 bar graph cannot give a 'proper feel'), or for testing small DC (CD player motors etc.) motors the analogue meter is king, likewise for certain peaking and nulling adjustments.

The digital meter being much more accurate in most instances for absolute measurement of course.
Horses for courses as they say, ideally both types of instrument should be available, and whichever is most suitable for the task in hand should be used.
It really also depends on which area of electronics you are predominately active in too.

Luckily I can, and do still use both.

Ps. I no longer have an AVO 8

The digital meter being much more accurate in most instances for absolute measurement of course.
Horses for courses as they say, ideally both types of instrument should be available, and whichever is most suitable for the task in hand should be used.
It really also depends on which area of electronics you are predominately active in too.

Luckily I can, and do still use both.

Ps. I no longer have an AVO 8

100% agree with those comments. I always have both on the bench as use either as required. There are still instances where an analogue wins over digital.

Rich

When I was a student I worked for a small Engineering company (Liskeard Engineering) in the Summer holidays 1974.
The Electrician was working on the bus-bars live whilst installing a new lathe.

He didn't himself come into contact with the power but his screwdriver vaporised just leaving just the handle.

The explosion left him traumatised and his face was "metallised" he also received burns to his hand and face.

He just froze rigid with his eyes open and his hand clenched tightly over the screw driver handle.

He was pretty ill for several weeks and I am not sure that he ever returned to work.

Its not just electrical shock to be wary of.

Cheers

Mike T

I still use an avo 8 and a fluke .
the avo is mainly used to monitor current and for quick checks on semiconductors.
HV diodes can be checked on the x100 range of the avo but not on the fluke.
both have there place .
rob t

Don't assume that low voltages are entirely harmless either. I know somebody who got his metal watch strap between his car battery +ve and chassis. A trip to A&E.

I have seen that happen, the chap got a nasty burn round his wrist. It wasn't me that time, I helped him release the catches on the wrist strap. The wound from my recent silly episode with a Mains battery portable is still a long way from healing, even after 2 weeks. So you can imagine how deep the burn went into the flesh.

I use an Avo 8 mainly for current measurement and my DMM for volts, resistance and capacitance and the occasional diode/transistor test.
Mike

I do not have an AVO 7 or 8 however I do have two AVO 9s and a recently restored AVO Electronic Testmeter and a pile of cheap DMMs. On the to do list is two mains fluke DMMs from the 1970s.
The AVO 9 is great for monitoring things that take a long time such as reforming capacitors you can leave it showing the currant and glance over from time to time to see how it is getting on without using batteries.
The Electronic Testmeter when set to voltage is analogue with a loading of 11 Meg so it has a bit of both with the disadvantage of requiring mains power.
DMMs are good for all the quick checks that you do as you go along.

I put my DMM's away for the project I'm doing at the moment so I was forced to use one of my AVOs for everything thereby, I hope, teaching myself something. I bought a Model 40 today at Flight Refuelling (and bumped into Luke - Mendipviews) which is outside on the patio submersed in foam cleaner.

Andrew

Hi Andy,

I don't believe the Model 40 was specifically designed for 'Sparks' but a re-design of the earlier 36-range AVO. However, I seem to recall it does have a couple of features which do make it more useful for electrical work the details of which are possibly in the large Avometer survey thread on UKVRRR.

Now removed of dirt and grease my '40' looks OK but a bit battered around the edges. Not sure what it's like electrically yet but nothing looks burnt and the meter seems to damp OK. Even if it's not,for £2 I can't complain too much as it will be used for parts.

Andrew

The AVO 9 is pretty much like the AVO 8.
The AVO Electronic Testmeter has its own restoration thread here.

Still on the AVO front, I also have a 'Model 71' minus probes at the moment, but was free from the "skip yard" a few years ago.. Almost a pocket sized meter, also popular with ex GPO telephone engineers (apparently) and hobbyists alike.

On the DMMs, I have a very useful Fluke 117, which is handy for measuring capacitance in addition to all the usual functions, and then one of those "odd job" cheapies from Wilko's for general use.

Marion

On the subject of "Robin" I have a Robin insulation and continuity tester, and very good Megger BM8A that I use to test for leaky caps.

Marion

I just put electrinic testmeter in the search box at the top of the screen and it came up a little way down the result.
viewtopic.php?f=15&t=3685&hilit=Electronic+testmeter

I put in Electronic Testmeter as that was in the title and got it closer to the top of the list.

Yes the power supply was a bit confusing at first but in the end I did get it sorted.
The scrap one did provide the bobbin resistors and leaves me with the parts to make up a mains PSU for something else with valves in it.
They do loose there meters quite often due to them being the right size for one of the popular valve testers as the scrap one did.

The old grey had a slightly greener tint to it and was very tatty. The grey I used was from an NOS tin given to me by a landlord whom could not be bothered with taking a load of paint away when he had finished renovating a house. I have used it on radiators without issue.

The good thing is that it has 11 meg input so readings compare with those of a DVM and also the movement has less damping than an AVO 8 or 9 making it excellent for looking at voltages that vary.
I must admit that I felt sorry for it and now I am pleased with it as a working instrument now I have got it restored regardless of what it was like to start with.