AVO Multimeter survey

[Sinewave]

I noticed that, there have been a few others too.

[Sinewave]

Out of interest, how rare is an 8x Mk3 panclimatic considered to be?

[Superscope]

Model 40 Update

As I alluded too previously, the Model 40 turns out to be "Typical ACWEECO",
in that a simple and straigthforward Numbering Scheme is
simply not going to keep anybody on their Toes enough.

So here goes:

Model 40 launched in 1939.
Since we don't know at which number the Serial Range started at,
we can't be certain of the Month of introduction.
If we assume it started around 0100, introduction was likely around June July.

The Sequence chosen was "Serial No" - "Date Code" which we are all familiar with,
but this was different to the then current Model 7 Format.

Around March 1942, the Model 40 Serial Number Format changed with a number
reset and a Prefix of "40" added.

Some time around August/October 1946, some body decided there were
to many Characters in the Serial Number, so the "0" in "40" was dropped,
whilst the Number Sequence remained unaltered.
This reduced the Serial Number down from 7 Digits to 6.

In 1947, the "40" Range sequence (Now really just "4") was dropped and
the Serial Number returned to the original Format.

It is not clear at this Time, how the sequence of numbers continued on,
as there is a break in continuity.



Ian

[Superscope]

Following on from the last post,

I thought I would separate this useful bit of information
as it relates to the Models 47A and 48A.

When the Model 40 moved to the "40" Serial number Format in 1942,
the Models 47A and 48A carried on using the original Model 40 Sequence,
as they had done from the start.

It seems, ACWEECO wanted to separate the Model 40 Variants properly.

In 1947, when the "40" Serial Numbers were dropped, it looks like the
Model 40 reverted back to the original Model 40 Number Range.
The 47A & 48A had of course, stopped being made by then.


Now, the interesting thing here is, the Model 47A(s version) logged in the Database all have a Model 40 Serial Number, which makes sence.
With one exception!

Dave's (The Philpot) logged a 47A(s version) with Serial No 17543-1144 R.
This is a standard 47A number, but the "R" may be a clue.

I think the Movement may be from a different Model 47.
I doubt we will ever know for sure.

Currently, 4 out of the 5 Model 47A(s versions) logged in the Database have a Model 40 Serial Number.

Because the 47 and 48 share the same Number Sequence, we are unlikely to
ever know how many of each were made.
It also makes it impossible to know exactly how many Model 40's were made, since
all three Models shared the same number sequence for a time.



Production numbers and Time line are still in progress so will follow later.



Ian

[The Philpott]

Thanks Ian, i will revisit my Model 47A(S) at some point to see if there are any such clues.
The handwriting on the scale plate does not seem to match any others i have looked at (it's perfectly good but a very individual style of script.)

Dave

[Sinewave]

Good grief, someone really wanted that.

[Superscope]

Ok, what have I missed ?





Ian

[Superscope]

Model D Update


Managed to find some time this Morning to carry on working with the estimates on Production numbers.

One interesting thing, that seems to be emerging from the Numbers, is just how slow
production seems to have been in the lead up to WWII.

As mentioned earlier, the Model 40's seem not to have ramped up production significantly until 1942.

Having looked at the Model D's, the Story is very similar.

Production Doubled from around 2000 Units (185 Units/Month) in 1941 to
over 4000 Units (365 Units/Month) in 1942.

Numbers remained fairly constant (but rising gradually) until the peak in 1945
with around 4800 Units made. (385 Units/Month).
Production coming to an almost grinding Halt after the War, with very few
made after 1945

The Model D, unlike the 47A and 48A, was definately still built after the War, but in very small Numbers.



Ian

[Superscope]

Sorry, I didn't make the point very clear in the previous post.

Production of Avo Meters in general, seems to have been quite slow
during the lead up to WWII.

The War started in September 1939.

But production of the Model 40 seems not to have really ramped up until 1943,
although, if we take the Model 47A into account, we can probably push that
back to nearer 1942.
Likewise, the Model D was not being kicked out at high levels until 1942.

What were ACWEECO doing I wonder?

Ian

[Aitor Eneko]

Originally Posted by Superscope

Following on from the last post,

I thought I would separate this useful bit of information
as it relates to the Models 47A and 48A.....

Thanks very much for the excellent job!!

My model 47A

[The Philpott]

Ian, i think Sinewave was referring to a rather old Avo that sold for in excess of £100! (Post 2606)

Post 2608- I suppose i equate the upsurge in production with similar geometric boost in the production of Spitfires, etc.

Dave

[pmmunro]

Ian,

I beleive that there is definitely a bit of a mystery revealed by the survey. The numbers of Avometers of all kinds, but especially Model 7s, which have made it to the survey from between the mid 1930s until around 1941/2 is surprisingly small. Not having been around at the time, I can only go by what we have been told by general historians that the UK was ill-prepared for the outbreak of war. It is possible however that preparations were more thorough than we are led to believe, at least in some respects, and that a high proportion of ACWEECO production was assigned to Government use in the years in question.

It can be seen from advertisements that Avometers were used by the armed services, as well as other Government agencies right from the beginning but how many of these made it into private ownership and hence have been reported in the forum? After the Second World War, significant numbers were sold off through the dealers who advertised in the popular and professional technical press but it's quite likely that these were central stores surplus and not ones which had actually been in service.

There are exceptions. For example I have a Model 40 from late 1946 in excellent condition which has the name Lt. P. Croydon. H.M.S Vernon on the instruction plate and Lt Cmdr, P. Croydon, RNVR HMS Vernon on the leather case. (For those not familiar with it's significant, HMS Vernon was the Torpedo Branch, also known as the Torpedo School).

I've wondered how an RNVR officer came to be at the torpedo school long enough to get his half-ring, especially after the war was over, but that is beside the point. Did Mr. Vernon consider that His Majesty had entrusted this meter to him personally, or did he provide it himself for the benefit of the Nation?

Extremely useful as it is proving, the survey must be, as was accepted from the beginning, skewed by the conditions under which Avometers survived. Meters with leather or wooden cases are often well preserved and it is clear that some owners made their own boxes for their cherished meters. Conversely, Heavy Duty Avometers with intact Bakelite cases are rare, probably due to their working conditions. The HD was not a model which is likley to have been bought in significant numbers by private users.

The survey is proving its usefulness, much enhanced by Ian's statistical collation of the data, but had any sales records survived, they would have been invaluable.

PMM

[Superscope]

I have completed the first Draft of estimated Production numbers.


Seems that most Avo meters had at some time or other, multiple Serial
Number Ranges running at some time during their production run.


Often, but not always running in Parallel with other number ranges.


Now, can somebody remind me when Avo Ltd celibrated their 1 Millionth Meter ?

My current figures put this around 1968, but because the Multiminor doesn't
normally have Data information, and so many of them were made, the date
of the No 1,000,000 is some what skewed.


Having gone through the Figures in depth, the one thing I didn't really
appreciate before now, is just how many Avo Minors and Multiminors seem
to have been made.

If the Figures can be trusted at Face Value, it looks like around
95,000 DC Avominors
180,000 Universal/Model 1 Avominors
280,000 Multiminors

Were made between 1933 and 1970.

During the period 1934 to 1945, the Avominors were built at almost
double the Rate of all the Full Sized Meters put together.




Ian

[Superscope]

Estimated Production Numbers from 1923 to 1945 are as follows:
This is the Total of all Meter types Manufactured during that year.

1923 = 1643
1924 = 1643
1925 = 1643
1926 = 1643
1927 = 1793
1928 = 800
1929 = 850
1930 = 900
1931 = 950
1932 = 1435
1933 = 6486
1934 = 31481
1935 = 7385
1936 = 8285
1937 = 12464
1938 = 13021
1939 = 15737
1940 = 15319
1941 = 19939
1942 = 39072
1943 = 36890
1944 = 37416
1945 = 36498

The only serious anomaly which I cannot explain, is 1934.
There seems to be a hugh peek in production of Avominors!

I have double checked the Figures, but this is what they are saying.
It doesn't look right to me, but I can't explain it away.

1923 to 1927 is estimated from the 8500 or so Model 1's manufactured
divided equally by the Five Years they were made.
1927 has the addition of Model 2's for that year.




Ian

[The Philpott]

Thanks for the further analysis Ian,

As regards the large numbers of 'minors produced around year 1934:
I haven't looked into this..but it has always seemed to me that the DC Avominor and Universal Avominor of that period were ahead of what little competition they had, for size, weight and comparative accuracy. Quite expensive, but backed by a firm that took warranty and after-service seriously.

Perhaps thinking commercially, sales were initially seen to match production and the concept of a 'pocket' multimeter was such a hit that inspired minds put manufacture into overdrive. (For all we know many of these units could have been stockpiled in the solid anticipation of future sales, allowing production to then be skewed towards Big Brother Avometers for sale to industry.)

Total 'stab in the dark' supposition needless to say..

Dave

[pmmunro]

Originally Posted by Superscope

I have completed the first Draft of estimated Production numbers.


Seems that most Avo meters had at some time or other, multiple Serial
Number Ranges running at some time during their production run.


Often, but not always running in Parallel with other number ranges.


Now, can somebody remind me when Avo Ltd celibrated their 1 Millionth Meter ?

My current figures put this around 1968, but because the Multiminor doesn't
normally have Data information, and so many of them were made, the date
of the No 1,000,000 is some what skewed.


Having gone through the Figures in depth, the one thing I didn't really
appreciate before now, is just how many Avo Minors and Multiminors seem
to have been made.

If the Figures can be trusted at Face Value, it looks like around
95,000 DC Avominors
180,000 Universal/Model 1 Avominors
280,000 Multiminors

Were made between 1933 and 1970.

During the period 1934 to 1945, the Avominors were built at almost
double the Rate of all the Full Sized Meters put together.




Ian

From "Avo News" July/August 1966

PMM

[Barnmead]

PMM in post 2612 has provided me with an answer to something that has puzzled me for some time. I have a nice wooden boxed Evershed-Vernon Potentiometer "Sweep (Staybrite) for recovery of torpedoes" I have always wondered who Vernon was! Thank you.

[The Philpott]

Intriguing, Vernon shore base named after the vessel that served as part of it's floating base? (If wiki is to be believed.)

I think we must have done quite well over the years at confusing the enemy! We were very much in the faslane..

Dave

[Superscope]

Thanks Peter,

Thats very encouraging.
The estimated production figures seem quite close then, to one of the only known facts we have.

If I spread the Multiminor production out a bit across its production span, instead of having a
single Total figure I had before, Number 1,000,000 falls nicely into 1966.

But, in order to make this as accurate as possible, can anybody confirm when
the Multiminor was introduced? I believe it was 1956.

When was it withdrawn?
I believe it will be around 1970 with the introduction of the 70 Series Meters.



Does anybody have any Date information at all, on any Multiminors they own?

We only have Two Dates reported in the survey, allegidely pertaining to the Multiminor.
But both these Dates are suspect, as they are 1945 and 1950.



Ian

[Barnmead]

One for the list with a story:

I have been contacted by a Dutch collector of WW2 material that was airdropped for the resistance who has a nice looking AVO minor with serial number 69982.541. He says that the AVO Minor is specifically mentioned in several dropping lists (see attached picture).