AVO Multimeter survey

[Pamphonica]

Originally Posted by Sinewave

Two lovely goodies have come my way very recently.

First, something I've wanted for a very long time is the Power Factor and Wattage unit made to connect to the PF sockets of the Model 7 and 40. It's complete with the leads. I've just yet to try and see if it's working. There's not much them really in circuitry, so it should work. No serial number on this unit that I can see.

Also, with a very warm welcome indeed, I introduce into my collection a 20 range Avometer, other wise known as the Model 3. Serial No.13-928.

Nice job. I finally found one of those PF adapters (Model 7 version) for a tenner at a rally a few months ago.


And of course big congrats on bagging a Model 3. I know you have been waiting a while for an early Avo. Where did it come from in the end?


-Jeremy

[Sinewave]

Was just in the right place at the right time. Still a few more to go!

[AndyGilham]

I've only gone and got myself an EA113, serial number 6908, and yes, it's the black moulding version.
I got this for £40 from a gent who's late father purchased it brand new.

Andy

[Pamphonica]

That's a lovely meter. Watch out - your addiction is showing...!
Jeremy

[AndyGilham]

Pamphonica,
All my purchases are towards the Avo/E&V heritage Centre. Hopefully functional within the next year. I have a lot of instruments in storage, ready for display.

Andy

[Pamphonica]

Yes, I know and appreciate what you do - maybe more a drive than an "addiction". At least you now know where all the nice AVOs are, thanks to this amazing thread.
I'm really looking forward to seeing the collection when it opens to the public, as are many other Avo afficionados.
All the best in your efforts,
Jeremy

[AndyGilham]

All,
I have been looking at the DC Avominors and Universal Avominors, and have constructed a spreadsheet of variants and part numbers.

I realize much of this should be within the database, but i wanted to look at dates and numbers. Since i have done this, i thought i would share.

I have tried to break down into the model types, and then orderd by serial number sequence, so in theory this gives the manufacturing order..... i then added in a function to calculate the numbers of instrument manufactured between each one listed. It gives us some ideas of volumes produced.

Andy

[Phil G4SPZ]

Hi Andy and thanks for taking the time to prepare this information.

How are you identifying the models? I have Universal AvoMinors with four distinctly different case styles, apart from the Type E, and from memory there are three styles of DC Avominor.

I’ll look through my collection - I’m not sure that I’ve reported all my serial numbers, so I’ll put that right to start with.

[pmmunro]

Andy,

This is very interesting information and shows that these meters where made in surprisingly large numbers, especially during the Second World war years.

It's easy to concentrate on the "full-size" instruments and not to realise that a significant part of the production resources must have been dedicated to Avominor manufacture.

Do you have any information of what was included in the numbers which were used to calculate when the millionth Avometer was made? I hadn't thought that Avominors might be included but possibly they were along with other specialised meters.

PMM

[AndyGilham]

To begin I just took the numbers from this forum, and from various other sites and gathered them. I based the model type on what was either stated, or by ordering the serial numbers and looking at the obvious groupings by serial sequence and date.
I like to think the groupings are correct.

Regarding the case types, for example the stepped DC Avominor case, i was not able to detail that info, but it wouyld be very useful. Most forum members give a serial number, but do not offer the case style.

Andy

[AndyGilham]

Just updated the DC Avominor PDF, I noticed the 'Instruments Made' column was missing

I have to say, I do enjoy gathering these stats and seeing the numbers comings out! Hoping to stumble accross 2 sequential serial numbers....... made by the same hands!

Andy

[Sinewave]

Here is that large CT38 I picked up recently complete in battleship grey!

[AndyGilham]

The CT38 is quite a beast! Have you opened it up yet? That incredible smell!!

Andy

[Sinewave]

Originally Posted by AndyGilham

The CT38 is quite a beast! Have you opened it up yet? That incredible smell!!

Andy

Yes I've had a look inside. I love the smell of these old pieces. Does your CT38 work?

[AndyGilham]

Sinewave
I have not even powered my CT38 up, I'm reluctant to. As I have said previously, I am mechanical, and avoid the magic electrons! It's all crazy witchcraft! I know where I am with a nut and bolt.

I need to get one of our hardware magicians interested in the collection!

Andy

[AndyGilham]

So I have recieved a new meter today, a High Resistance Mark 1,with serial number 591-848 (August 1948). I tried to add it to the survey, but it seems HR instruments are not listed??
Looking at the latest Survey document, this meter falls just before another from August 1948 (693-848). So it seems at least 100 HR meters that month!!

The instrument movement need some attention, it seems the frame is slightly loose from the panel, and the needle is not free to move.
Other than that its in a reasonable state. It was last calibrated in 1985, and still had the calibration label over the screw recess.

There are 6 wound coils detailing the patent numbers, and seems a lot of additional resistors (compared to the HR images on Richard Radios).

The instrument came in a wooden box with leads and clips!

Not bad for £33

Andy

[The Philpott]

Very similar to mine Andy, which curiously, has the serial 593-748!

Although..slightly different versions of the HRM appear to have had their own series of numbers (eg 5meg/20meg versions. screened and unscreened cases..)

Your one, if I recall from the listing, doesn't suffer too badly from the red text fading. Mine has spent too long in sunshine, faded to beige but just about legible.

Dave

[AndyGilham]

Mine one is the non-screened version, with the blacked out text on the instruction plate.

Yes it has fantastic scale, very clear red lettering!

Andy

[The Philpott]

..So that's the same version as mine, instrument No. 593 is dated July, instrument number 591 is dated August. Such anomalies must come about as one months rolls into the next.

The handwriting on your scale-plate is certainly from a different employee.

Almost got sequential numbers there!

Dave

[AndyGilham]

Dave,
Although almost sequential, they are a month apart! These sequential numbers do not seem to tie in order with dates. It's all very confusing.......!

Andy