AVO Multimeter survey

[Barnmead]

i don't know if this is of interest but the production of the multiminor and the model 70 range overlapped, I have a 1972/3 ITT Electronics Stock Catalogue which lists:

Avo72 @ £15.50 [described as the first of a new Avometer generation]
Multiminor Mk4 @ £12.725
Avo 7 Mk2 @ £32.00
Avo8 Mk4 @ £34.80
Avo9 Mk4 @ 34.80

No mention of the models 70 and 71

[pmmunro]

Originally Posted by AndyGilham

Ian
The serial number for Multiminor are elusive, and none of meters I have include it.
However, I just had a look in the archives and found a list of official variants.

Multiminor Model 1 (Standard Accuracy)
Multiminor Model 1A (High Accuracy)
Multiminor Model 2 (Standard Accuracy / Panclimatic)
Multiminor Model 2A (High Accuracy / Panclimatic)
Multiminor Model 4
Multiminor Model 5
Multiminor Model 5 Services
Multiminor Svenska Special
Multiminor IBM Special
Multiminor Home Office Special

So that's quite interesting! And certainly no sign of a Model 3...

Andy

That is interesting Andy; I didn't know about the last three. It seems that the Swedish armed forces had a liking for special versions of Avometers; I have two Model 8 variants which seem to be designed as 10,000 ohms per volt meters. You have to wonder why.

As far as I have been able to trace from advertisements, there never was a Mark 3, just as there doesn't seem to have been a Model 9 Mk III. Maybe someone in marketing had something against the number 3, perhaps it did prove to be a crowd for him at some critical time!

The 1A, 2 and 2A are quite rare, possibly something to do with the pricing?

PMM

[Barnmead]

another avominor for the list:

41759.36 with stepped sides in box with space for leads under meter.

[Superscope]

Hi Richard,

The 1972/3 ITT Electronics Stock Catalogue seems to mix
things up a bit.

Some overlap of the Multiminor and the 70 Series would be
expected, but the fact that the Multiminor stated is a Mk 4
and not a Mk 5 is a bit odd.

Likewise, the fact the 70 Series is a Model 72 and not a 71
is also unexpected.

I wonder if the Catalogue was listing existing/Left over Stock?

The Model 8/9 Mk IV was still being manufactured in 1972, but
1972 was definately also Model 8 Mk V territory as of course
was 1973, but seems to be missing in the Listings.

Was there any mention of the 8 Mk V anywhere?

The description of the Model 72 being the first of a new Generation
is also odd, unless by some quirk of Marketing it was released
before the 71 which doesn't make sence.
Might just be ITT Sales Hype.

There is virtually no difference between the 71 and 72.
The 72 has slightly tighter Spec with +- 2% FSD Accuracy,
whereas the 71 is stated as 2.5%

I can't see any differences in the Circuit, so maybe slightly better
componants were used.
The Service Information says all the 70 Series had basically the
same Movement.


Ian

[Superscope]

Hi Richard,

Another couple of questions for you, if you don't mind?

Was there any update from your contact in Holland
regarding confirmation of that Serial Number?

Also, does the DC Avometer you posted on #2643
have a "." between the Serial and Date, or a "-" ?



Thanks

Ian

[Barnmead]

Ian

Sorry I’ve not heard back from him but will let you know when I do. Perhaps a gentle reminder is in order.
Difficult but with a magnifying glass I think it must be a short dash.

[Barnmead]

Ian

Just had another look at the catalogue, there is no 8 Mk 5
Catalogue has over 1200 pages so I imagine would have been prepared in late 1971
The model 71 was I think short lived, perhaps not many were made.
As you say a bit of a puzzle.

[Barnmead]

Ian

Your query in 2621

I have now had a response, he has two, a DC and a universal model, he sent me two pictures.
69982.541 and 77471-545 can be clearly seen. The first seems to be a stamped number.

[Superscope]

Thanks Richard,

You can't argue with a Photo.

The Number is still a mystery though.
I can't fit this in with the current Number sequence thinking.

By all rights, it should be a 1942 Meter.

The only explaination I can think of at the moment, is that one
of our existing Numbers is reported incorrectly.
Which does happen quite a lot.

Since we have very few DC Avo Minor Numbers during the War Years,
a single mistake might, not only not be spotted, but it will Skew badly
any attempt to identify a Pattern.

We only have Four DC Serial Numbers during the War.
Two are HR Avominors, so a completely different Number Range,
and Two DC's from 1941 and 1943.

We have no Data at all from 1937 - 1940, 1942, and 1944 - 1945.

Since the Dutch Meter's Serial Number is virtually indisputable, I will
put a Question Mark on 65222-1041 which forms the current thinking.

This will change the estimated production Numbers of DC Avo Minors
in an upwards direction.

So the Hunt is on, for more DC Avominors Numbers.


Ian

[micheal]

Re war years DC. AVOMINORS
I have two, numbers have been double checked

61836-840
64983-941

Mike

[AndyGilham]

Originally Posted by Barnmead

another avominor for the list:

41759.36 with stepped sides in box with space for leads under meter.

Interesting serial, the Megger collection includes 41779-36, just 20 instruments later than yours. So yours will have stepped sides and no extra socket, so 13-range.

Andy

[AndyGilham]

Originally Posted by Barnmead

Ian

Your query in 2621

I have now had a response, he has two, a DC and a universal model, he sent me two pictures.
69982.541 and 77471-545 can be clearly seen. The first seems to be a stamped number.

Both those meter were already on my list, as they were up for sale on Ebay a little while back (different sellers). Seems we have found the buyer!

Andy

[AndyGilham]

Originally Posted by Superscope

Thanks Richard,

You can't argue with a Photo.

The Number is still a mystery though.
I can't fit this in with the current Number sequence thinking.

By all rights, it should be a 1942 Meter.

The only explaination I can think of at the moment, is that one
of our existing Numbers is reported incorrectly.
Which does happen quite a lot.

Since we have very few DC Avo Minor Numbers during the War Years,
a single mistake might, not only not be spotted, but it will Skew badly
any attempt to identify a Pattern.

We only have Four DC Serial Numbers during the War.
Two are HR Avominors, so a completely different Number Range,
and Two DC's from 1941 and 1943.

We have no Data at all from 1937 - 1940, 1942, and 1944 - 1945.

Since the Dutch Meter's Serial Number is virtually indisputable, I will
put a Question Mark on 65222-1041 which forms the current thinking.

This will change the estimated production Numbers of DC Avo Minors
in an upwards direction.

So the Hunt is on, for more DC Avominors Numbers.


Ian

My spreadsheet of DC Avominors now contains 85 serial numbers. I have also logged whether they are stepped, and what range 10, 13, or 14.
(Also 6 HR Avominors)

My Universal Avominor list now contains 133 serial numbers
Also:
9x Model 1A
11x Model 2
21x Model E
8x Model U15
4x Protim

I need to get it organised and uploaded

Andy

[Superscope]

Thanks Mike,

I didn't have those Numbers, so they help.
I don't know if Andy had them?

Your numbers fit in perfectly with the sequence
as I understood it to be.

69982-541 though, is still a mystery.

There is obviously something else going on here, which
hopefully time and more numbers may sort out.

It would seem another Number Range might be going on, but at
69 Thousand, that is still difficult if not impossible to fit in.

I wonder if it is just something very simple, like a Typo when
the Scale went for Labelling?

One thing this has cleared up, of the Two Ranges I knew were running
during the War Years (not incl the HR Range), the 60 Thousand Range are obviously all DC
Avominors, whereas, the 40 Thousand Range are Universals.
As I mentioned, these details were not recorded originally.


Andy,

I thought I had all your Numbers recorded in the Database, but clearly I am missing some.
Currently I have:

50 x Avominor DC
5 x AvoMinor HR
141 x Avominor Model 1
4 x Avominor Model 1a
7 x Avominor Model 2


Although, since the Model Number was not specificly asked for originally,
there are some AvoMinors probably in the wrong catagory.
I correct them as I go along when new information is available.

So the Survey Total for Avominors of all flavors, is currently 207.

When you release your next list I will cross reference the Database and correct any discrepancies or add any missing Numbers.



Ian

[AndyGilham]

I seem to have in total, 278 Avominors (DC and Universal)

For the DC Avominor, my list includes:

1939 x 6 serials
1934 x 19
1935 x 2
1936 x 8
1937 x 4
1938 x 3
1939 x 2
1940 x 7
1941 x 7 (+1 anomaly we have discussed)
1942 x 3
1943 x 7
1944 / 1945 x 0
1946 x 7
1947 x 7
Plus some later from 1950's.

Andy

[micheal]

Dc Avominor 69982-541 may have had a movement transplant

Mike

[micheal]

Sorry please disregard last post transplant wouldn’t make any difference
Brain sized

Mike

[The Philpott]

Not sure if i submitted these DC Avominors.
64206-641
42653-96 (The '3' for the 1930's decade is assumed.)

There are inevitably going to be occasional foul-ups found with so many numbers applied by hand. I have a Universal Avominor Model 1A whose number is included in the Model 1 sequence, making it appear more commonplace than it is.

Dave

[Superscope]

Thanks Dave,

These are new Numbers as regards the Database.
I didn't have these.

Can I confirm if any of these are Stepped ?

Can you tell me what the Serial number is, of the Model 1a you think is in the wrong Catagory?
I will correct it if it is recorded incorrectly.



Ian

[AndyGilham]

Both of Dave's Avominors will have stepped sides and be 13 range (Without center socket).
The change to Stepped sides happened somewhere between November 1935 and January 1936. Exactly the same time it went from 10 range to 13.

The change to 14 range (Extra socket added) happened in late October 1941

Andy