AVO Multimeter survey

[The Philpott]

...You've been converted..
An extra advantage is their size, weight and (low) value means very little 'steal appeal'.

Dave

[Barnmead]

Another for the database.

I have been sent photos of a Model 2 No. 2348. from Rochester Row, with ‘grained’ front panel surface finish

[factory]

Here is an AVO 8 MkIII that I have had for a while, the serial is 54855.267 and the case was engraved by it's original owner Marconi, sadly the movement appears to have failed O/C.



David

[NBSTech]

I have an Avo 8 MkV serial: 08788, it also has 8V/2/80 printed next to it.
it's in good condition, is annually calibrated and still in regular use.

[6SN7WGTB]

Just acquired a virtually mint Test Set No.1.

Sadly the courier managed to play football with it, and the large AC transformer had broken from its mountings.

All now repaired and it calibrates correctly against my Fluke 87 on all ranges.

A really lovely meter. There is something about the gentle swing of a needle!

SN 9691 - 10 - 70

[Sinewave]

Usually happens when not packaged properly for transit.

[rogerggbr]

New member here.

I have 2 model 7s:-

7442-6957 which I inherited from my dad. He would have used it at work in the 50s and 60s and then at home in the years after.

51580-A-1154 also marked ZD 00021 which I think makes it ex-military. I found this a few years ago abandoned in a cupboard at work and thought it deserved to be saved. I removed the batteries (yes they were still in) and cleaned it up a bit.

Both still work, but are not used regularly any more. I have put the above in the new database as well.

[The Philpott]

Howdy. Yes, ZD00021 is military, probably the army.
A quirk of the Model 7 is a very tiny current is drawn from the cell when set to AC ranges. Presumably this is to compensate for losses across the rectifier. Ideally in storage therefore they shouldn't be left on an AC range. (In reality it's not an issue, but i wouldn't like to bet on it if a Duracell was involved!)

Dave

[Superscope]

Hi Rogerggbr,

Welcome to the Forum and thanks for the Serial Numbers.

Can you tell me the type of back Case your Model 7's use ?
i.e. If they are Bakelite or Pressed Alloy.

If Alloy, what Colour are they painted.

Also, what type of Battery Cover do they have ?

This will help further our understanding of what
was actually being produced by the company.

Ian

[rogerggbr]

Hi Ian,
To try and answer your questions, both are pressed alloy back but have different battery covers. The ZD is plain alloy, the other has a moulded plastic cover which also holds a couple of extra probes. Both are grey hammerite (or similar) finish.
I have attached a couple of pictures, one showing the battery cover of the 7442-5957 and the other showing the very nice compliments slip from 1959 when it appears my dad requested a copy of the manual.
Roger

[Analogue man]

AVO 8 Mk5 81691
AVO Multiminor Mk5 37062
Heavy Duty AVO 5471 1055

[AndyGilham]

Its been a while, i hope everyone is well.

A Universal Avominor Model E has been donated to the Megger collection.
The instrument serial is E.4807 1942 and so quite an early variant. In fact its the 4th earliest variant I am aware of. Interestingly it has raised plastic around the terminals which I thought had come in later.
This is strange, since the earlier cases included the Pheon and TESTMETER TYPE E moulding, but this is the later option. Additionally the scaleplate and rear instruction plate both reference 10A/10613, which is the older AM stores reference.

I believe that maybe its an early instrument, that has been transplanted into a newer enclosure.


The instrument came with leather case (in almost perfect condition) and the leadset.

Its in reasonable condition, apart form the missing Fuse (E) cap.

[Beardyman]

AVO8 MK3 recently acquired, all working & in generally good nick.
Serial number on the scale is:
53864.267

[Paul_RK]

And an Avo 8 Mk II: 105998-C-460

[The Philpott]

Interesting- Have just seen a Model D Avometer for sale which has 'Model 7' text on the facia moulding. I have seen many wearing 'Model 40' on the frontage, but never Model 7.
Instruction plate on rear shows '10A' not '10S', which presumably means it's quite an early one. The Z screw is bakelite not nickel plated brass however.

Dave

[Superscope]

Yes, I've been watching that one for a Day or Two now.
The Model 7 Panel caught my Eye as well.

The Model 7 Panels seem to be quite Rare and I only have one
Model 7 Meter with this type of Panel, so it's odd one turns up
on a Model D of all places.
The Model 40 Front Panels seem a lot more common.

Since you brought the subject up Dave, I've been meaning
to ask the Forum Members on this Thread if they could report
any Meters they have Bearing a Model 40 or Model 7 Front Panel.
I've been recording this Data for a while now quietly in the background.

But now would seem like a good time to ask, as the Thread has been
quite quiet for a while.

Likewise, I think this is probably an early example, but you just can't
assume anything with Avo, so we need the Data.

I'm guessing some old Panels were probably knocking around for years
lost in Boxes on the Top shelf until the needs of the War effort
bought them out.



Ian

[AndyGilham]

Ian
I have 3 instrument bearing the Model 7 or Model 40 motif.

1. Model 7 with 'Model 7' motif panel. 7129-3427 (December 1939)

2. Model 40 with 'Model 40' motif panel. 4486-541 (May 1941)

3. Model D with 'Model 40' motif panel. 1269-1141.1949 (November 1941)
The move,ment looks to have been repaired or replacement in 1949 (Penciled on rear of scale)
This Model D variants is marked 10A/10610 on the rear instruction plate, but 10S/10610 on the scaleplate.

Andy

[Superscope]

Thanks Andy,

Database duly updated.

You had me going with that Model D.
I thought for a minute we had a new Number!

I haven't got my head round the 10A / 10S Military codes yet.
They all seem to be a bit random.
Sometimes the Scaleplate and Dataplates match, other times they
don't.

Maybe we should start recording that as well, what do you think?
Is it a worth while addition to the survey?


Ian

[peterpixel]

I have three Avometers to own up to.
1. Model 8 10116-c-153 No 500v dc range mk1?
2. Model 8 105483 1069 Has 500v dc range but no mk II or III markings.
3. Avo Multiminor mk 4 but cannot find serial number.
All working ok. Peter.

[Superscope]

Thanks Peter,

The age of your Number 2 Meter would suggest it is
either a Mk IV or possibly a Mk III.

1969 was the change Year from Mk III to Mk IV.



If it is a Mk IV, the back plate should be a large Aluminium cover
almost the size of the meter and say
"Universal Model 8 Mk IV, Model 9 Mk IV"
Access to the Battery's is from the back.

The Data Plate was the same for both the Model 9 Mk IV and the Model 8 Mk IV meters.

If it's a Mk III, the Data Plate on the back would normally say so,
but not always.
But access to the Battery's will be at the Top like the previous Meters.

A photo of the Back of the Meter could probably confirm what you have.


Ian