AVO model 8 Mk. 5 - UK Vintage Radio Repair and Restoration Discussion Forum

sparkymike · 2nd Nov 2018, 10:12 pm

I have just bought an Avo Type.8 mk.5.for very reasonable price.
This meter would seem to be unused from new and has the warranty book/instruction book and a small leaflet that has space for serial no. but none listed? I can't see any serial numbers on the dial but there are some numbers at the bottom of the dial, but nearly impossible to read as the case obscures them.
There is a 15volt B154 in the leather case and it would look like this was never fitted. The larger HP2 battery is not present.
Is it possible to build a replacement stack that will fit the plastic B154 cradle and possibly better still a re-chargable one ? Another question, which battery does what in these Avo's? I always forget, must be old timers syndrome !!
Mike.

Electronpusher0 · 2nd Nov 2018, 10:43 pm

The batteries are used for the resistance measurements, the 1.5V is used on the lower ranges and the 15V on the highest range.
It is certainly possible to build a replacement using a stack of lithium cells.
This thread discusses how
https://www.vintage-radio.net/forum/...ad.php?t=55216

Peter

sparkymike · 3rd Nov 2018, 8:50 pm

Thanks for that.
One other point, there are two clip on probes in a plastic wallet with this meter. Were normal probes also supplied in the kit ? The clip on probes, as supplied, are very slender and will be quite handy. There are also two of the croc type clips in the kit.
Mike.

Superscope · 4th Nov 2018, 1:48 pm

Hi Mike,

The Conical shaped Probes in the Plastic Wallet were as far as I know,
supplied as Standard with the Mk V onwards and probably with earlier
Mk's as well.

If you are going to use these in anger, check that they have not gone
High Impedance. See Thread below:
https://www.vintage-radio.net/forum/...d.php?t=147541

With reference to your first Post, the Mk V's for some reason, have a habit
of losing their Serial Numbers.
It would originally have been on a Label stuck on the Side of the Case.
This Label was usually (but not always) replicated inside the Battery Bay.
They are often missing, either accidentally or I'm sure were often removed due to an unofficial change of Ownership!

The Mk V also for some reason, doesn't always have a Date Mark, even if
the Serial Number is available.
Seems AVO simply didn't always Date them for some reason.

Ian

sparkymike · 5th Nov 2018, 8:25 am

Thanks Ian for the info. On closer examination this meter and case seem to be unused since new. Its destined to sit in the cupboard, as it is too good for the workshop !! If I get a chance I will post photos.
Mike.

2nd Nov 2018, 10:12 pm	#1
sparkymike Octode Join Date: Dec 2006 Location: Colchester, Essex, UK. Posts: 1,076	AVO model 8 Mk. 5 I have just bought an Avo Type.8 mk.5.for very reasonable price. This meter would seem to be unused from new and has the warranty book/instruction book and a small leaflet that has space for serial no. but none listed? I can't see any serial numbers on the dial but there are some numbers at the bottom of the dial, but nearly impossible to read as the case obscures them. There is a 15volt B154 in the leather case and it would look like this was never fitted. The larger HP2 battery is not present. Is it possible to build a replacement stack that will fit the plastic B154 cradle and possibly better still a re-chargable one ? Another question, which battery does what in these Avo's? I always forget, must be old timers syndrome !! Mike.

2nd Nov 2018, 10:43 pm	#2
Electronpusher0 Nonode Join Date: Jun 2016 Location: Bognor Regis, West Sussex, UK. Posts: 2,294	Re: AVO model 8 Mk. 5 The batteries are used for the resistance measurements, the 1.5V is used on the lower ranges and the 15V on the highest range. It is certainly possible to build a replacement using a stack of lithium cells. This thread discusses how https://www.vintage-radio.net/forum/...ad.php?t=55216 Peter

3rd Nov 2018, 8:50 pm	#3
sparkymike Octode Join Date: Dec 2006 Location: Colchester, Essex, UK. Posts: 1,076	Re: AVO model 8 Mk. 5 Thanks for that. One other point, there are two clip on probes in a plastic wallet with this meter. Were normal probes also supplied in the kit ? The clip on probes, as supplied, are very slender and will be quite handy. There are also two of the croc type clips in the kit. Mike.

4th Nov 2018, 1:48 pm	#4
Superscope Octode Join Date: May 2017 Location: St Austell, Cornwall, UK. Posts: 1,018	Re: AVO model 8 Mk. 5 Hi Mike, The Conical shaped Probes in the Plastic Wallet were as far as I know, supplied as Standard with the Mk V onwards and probably with earlier Mk's as well. If you are going to use these in anger, check that they have not gone High Impedance. See Thread below: https://www.vintage-radio.net/forum/...d.php?t=147541 With reference to your first Post, the Mk V's for some reason, have a habit of losing their Serial Numbers. It would originally have been on a Label stuck on the Side of the Case. This Label was usually (but not always) replicated inside the Battery Bay. They are often missing, either accidentally or I'm sure were often removed due to an unofficial change of Ownership! The Mk V also for some reason, doesn't always have a Date Mark, even if the Serial Number is available. Seems AVO simply didn't always Date them for some reason. Ian

5th Nov 2018, 8:25 am	#5
sparkymike Octode Join Date: Dec 2006 Location: Colchester, Essex, UK. Posts: 1,076	Re: AVO model 8 Mk. 5 Thanks Ian for the info. On closer examination this meter and case seem to be unused since new. Its destined to sit in the cupboard, as it is too good for the workshop !! If I get a chance I will post photos. Mike.