Hi Dave, this was obviously originally made for the military, the Z4/ZDA number is an army stores reference. On the lid, the 6625-99-xxx-xxxx is its NATO stock number (NSN). The other giveaway is on the schematic, where the transistors have their military equivalent given - the CV number. Now in British army terminology, CV stood for 'common valve' and valves all had a CVnnnn reference. Now when transistors came along, the military didn't know what to do with them and the guy that made the decisions was on leave. So they took the option 1 (do nothing) path and called them CV as well. The 'bodge' you see on the wirewound resistors is easily explained- and it isn't a bodge. Those are precision resistors, and they will have been made with a 'tail' of an inch or so of surplus resistance wire hanging out. During factory calibration, the soldered joint will have been moved up or down the tail to bring it into cal- and we are talking a tiny fraction of an ohm, serious precision! So credit where its due.... bodge indeed!!
In the video @ 15:45 it shows hand wound resistors. The insulation is described in its tongue-twister name as "Double Cotton Covered Copper Wire". I use to work at AVO in the late 60s and it was my job to wind those. They were then painted with a lacquer to stop them unwinding.
@@rivets1001 I was an apprentice there after I left school in the late 60s. I spent my 7 years there in their "clean room" where they assembled the meters. That led me onto a career in electronics at the University of Kent at Canterbury. I stayed there 42 years until I retired 4 years ago. Did you work there?
Dave, I'm an engineer from the early 1970s. Testers like that one were used to match transistors for push-pull circuits. There were easier ways to find bad transistors. But fancy testers like that were for matching parameters, often with thermal influences. In the 1970s, the industry moved to Tektronix oscilloscope-style transistor testers with built-in sawtooth generators for displaying the gain curves automatically. Also, the Texas Instruments 7400-series logic I/Cs were not 1962-ish. Think more late 1960s. CMOS 4000-series were even later, circa 1972-ish if my memory serves. Transistors reigned supreme in the 1960s. Even inside Iron Man's suit. In the comics of the 1960s, everything in his suit was "transistor-powered". I'm sure Tony Stark would have had a tester like your Avocet.
Best birthday gift ever. An EEVBlog video :D Didn't get to watch it on my birthday sadly but hey, I still enjoy it either way :) I also vote to have you power that baby up and see how it does after 50+ years. Thanks for everything you do for us Dave. Been catching up on videos from the beginning, every day after work I watch a little more. Been waiting on my approval into the forum for ages though D: but watching your videos makes it worth the wait haha.
I know it's an old video, but if you still got this vintage transistor tester you should send it to Mr Carlson's Lab, he will have it working better than new in no time.
Hi I started my apprenticeship in 1973 at a REME works and we had to do all wire looms with lacing cord. if you look closely you should not see any start or end knots. The start you can wind over itself and the end you form a loop and pull the end through the multiple wraps.
I use to be on the production line for this instrument. A lot of the batches were made for the military. They had to be waterproof so we had a giant bath of water. They had a "Tyre Valve" for pressurising them before being submerged to detect any leaks i.e. bubbles.
Thanks for the video it is certainly well built. The 2 small capacitors are meter protection diodes and the plugs in the battery compartment are held in place by bumpers on the main chassis
Lovely bit of kit. I have an AVO VCM163 tube (“valve”) analyzer, probably from the 70s. ACO was most famous for their tube analyzers. While the VCM163 tests vacuum tubes, it uses solid-state active parts inside. I think it’s the best of the service tube testers ever made.
Great bit of kit, Avo build quality is second to none. I love the battery holders, they are actually screening cans for signal valves! Please replace those leaky caps and fire it up, would bet it will work fine.
Great piece of gear Dave, I've used some of the old Transistor Testers in the USA vintage late '60's, early 70's but never one that old. Great video as always!
The "mid air" tie point at 16:00 is actually where they adjust the resistance value by melting the solder and sliding the wire to tweak the resistance.
I'd say that they would've just measured the resistance with a meter to determine the soldering point as it being tinned with solder would lower it's resistance over the tinned part of the wire, leaving much more to flap in the breeze, not really desirable.
MOD Record is the "Ministry Of Defence" here in the UK and the number stenciled on the front of the case is a NATO Stock Number. Also the brass date plate has the MOD "Crows Foot" mark on it, it's the little arrow, every British Military Item tends to have this mark on them.
Like the way they have mounted the diode with spring leg, so it not will be physical stressed. (21:35) The old oc transistor could be sensitive to 50/60 hz light if paint was scratched of.
Hit the nail on head perfectly at 11:30 when you said "Somebody really took pride in that". They actually cared. We were actually building the product ourselves. Not by a 3rd world country. And when building a product that lasted a lifetime was a good thing. It is always so refreshing to see these old-school well-built products. They represent a time when people actually gave a shit about something other than themselves. ☺
Wow reminds me of my days in Communications and Electronics Section of the Brigade Headquarters, where we did in depth repair of everything from FM Radio Transceivers to Teletype machines back in 1970. We had devices designed in this exact manner so as to stand up to the conditions we encountered in Vietnam.
The size batteries that would fit in the u10 (D: ~20 mm; H: ~59 mm) holder would be: "A" Cell (D: ~17 mm; H: ~50 mm) Usually Ni-Cd or Ni-MH "B" Cell (D: ~21 mm; H: ~60 mm) "AA" Cell (D: ~14 mm; H: ~50 mm) Possibly a "Sub-C" Cell (D: ~22 mm; H: ~43 mm) Ni-Cd or Ni-MH "5/4Sub-C" Cell (D: ~22 mm; H: ~54 mm) Ni-Cd or Ni-MH I work at Batteries and Bulbs in the US. You can find the "B" Cell in 4.5V Lantern Batteries and the "No. 8"
I would love to see a repair / recapping of this piece of art. And it needn't be old age as such that caused the condenser (heh) to fail, it could be as simple as the meter having been sitting unused for quite some time and then someone coming along trying to power it up. My electronics teacher taught us students to always ease things containing electrolytes coming from mothball status by gradually increasing the voltage over them, partly because failures tend not to be as catastrophic, partly because you in some instances could rejuvenate the condensers. As to transistor testers, back when I was in electronics school, we didn't have transistor testers as such, but we did have standard test schematics we used together with the parts bins, a function generator and a scope (sometimes a diff probe) to breakboard a circuit so we could see all the relevant curves of a discrete. Oh, and looking on my battery cheat-sheet, the dimensions of the R12 is ∅ 21.5 H 60, so a piece of plastic or cardboard tube around an AA/R6 and washers on the spring end should do the trick. With a quality Alkaline cell of course.
I'd love to see this thing in action! Try using C cells for the batteries, they're the same length as AA's after all. Also, that dodgy cap should be an easy replacement, but IMO it deserves a high end cap, if only to keep the overall build quality at a similar level as when it was first built. After all, if you don't respect your test equipment, it won't respect you. ...or something like that. Treat stuff right and it doesn't cause problems, that kind of thing.
IR2E1 - did you test to see if that is an old diode / rectifier or even a zener Dave? I did notice one on the schematic. Just found a Mk. 2 that sold for £225.
Can't believe I've missed this video until now; I have the same tester which I was given back in about '84 because my school's electronics depertment were going to dispose of it. I also have the manual and the transistor data book that it originally came with, although AVO never sent my updated book when I returned the included post card! I believe the cells are A cells.
wow Dave... you have a lot of cool stuff on this channel, but this might be the most beautiful of all. stunning build quality. funny how far we've come in electronics since then, but the days of such loving mechanical craftsmanship may be gone forever, at least outside of vehicles... I grew up in the 90s when most stuff had already gone plastic but I still feel drawn to old high end analog more than anything... combine this outside with the agilent RF meter inside and you got the ultimate gear quality
The great thing about AVO kit is that, even if it's completely buggered through the passage of time, it still feels, looks and smells like handmade quality kit :)
The AVO Model 8s were handmade by a production line of ladies hand soldering every joint. No PCBs anywhere. I know because I was an apprentice on that production line. I've never been so embarrassed due to the things the ladies talked about, you can imagine.
I would love to see this thing operating, I'd be curious to see it test modern transistors. Maybe do ten from the same batch and see what variances there are. Because people don't test them anymore, the variances could be quite large.
Hi Dave. The arrow on the tag is a 'broad arrow' indicating property of the UK government (also used by other commonwealth countries, including Australia). The label inside probably doesn't stand for 'modification', but Ministry Of Defence.
Hello greetings! When repairing electronic equipment such as amplifiers, there are some defects such as microleakage in transistors that cannot be detected as shown in the video. The only way I can find them is with an analog multimeter from the 80's, like the Hioki AS100D or Sanwa 320x. I'll give you an example: The Hioki AS100D multimeter has a x100k scale that works with a 22.5v + 3v battery for a total voltage of 25.5v. Added to that, a super sensitive galvanometer that works with 9 microamps. Becoming an ultra effective instrument in detecting micro-leakage in semiconductor junctions. How do you manage to detect these small leaks with the digital multimer? Or is there any other instrument that can do this?
Rob Fenwitch Didn't realise it went back that far, but the WP article says they formed a partnership in 1923, became a fully-owned subsidiary in 1927 and the Mullard name was dropped in 1988. I did a tour of their Mitcham plant in the mid 70s. The place was half empty as valve production had all but ceased.
CV2400 per google was a prototype transistor developed by the GPO in or around 1956; This is the Post Office prototype transistor from about mid 1956. Selected for Noise factor of 6dB. Ge Junction Alloy. PNP
Electrical Equipment of Australia LTD lasted 9 years before it was taken over in 1984 by Amalgamated Wireless Australasia Limited, or AWA. From everything i can find, they were a reasonably successful company. Which i guess you would have to be, to be taken over by the AWA in the mid 80's. Their former offices at 75 Liverpool, is now a seafood restaurant. LOL, how times change.
hard to believe, that AVO was first made by a post office worker in London, and now AVO are part of megger, another british company that STILL make products in the UK, been past their dover factory a few times too! :D
Dave. It would appear this bootiful instrument has a military past as it has the 'crowfoot' mark. The Z4 / ZDA 0929 is probably a military identification number. It was most likely contracted to AVO as a 'must have' at the time and remained in storage -unused!
Man I would love having an electronic's desk filled with this old equipment. Already got an oscilloscope and two vacuum tube voltmeters from the 70s made by Heathkit..
EEVblog But what about AA cells? The power consumption shouldn't be too large for a precision meter movement and low power high frequency generator. Edit: I wrote before watching the video to the end. I would love to see it work too.
Power the beast up and have a play, btw, the connectors that were uncliped are most likely held secure against the body when the battery assembly is in position..
I have a container with over a hundred TO-5 packaged germanium transistors which came out of a 1960s-era Dymec computer-controlled integrating voltmeter. (Yes, computer-controlled, as in you could control the range selection and receive the output in BCD format over a serial cable). I pulled out each one and individually tested them with my Heathkit IT-18 transistor checker.
'Made in England' Do we make anything anymore? The upward pointing arrow on the brass plate at 0:46, is that a WD (war department) mark? This might explain the build quality. I could 'smell' the electronics through Dave's enthusiasm :-)
Hello Dave, that's a very interesting thing. I'd love to see it working. Why don't you make another video of the transistor analyser while testing a few standard components like the BC547? Greetings from Munich, Germany. Cyberfuzzy
Noise control knob may be put back on wrong by someone. Other than that, this specimen is nicely kept, probably a part of clean room equipment thus the lack of corrosion.
Hi Dave, this was obviously originally made for the military, the Z4/ZDA number is an army stores reference. On the lid, the 6625-99-xxx-xxxx is its NATO stock number (NSN). The other giveaway is on the schematic, where the transistors have their military equivalent given - the CV number. Now in British army terminology, CV stood for 'common valve' and valves all had a CVnnnn reference. Now when transistors came along, the military didn't know what to do with them and the guy that made the decisions was on leave. So they took the option 1 (do nothing) path and called them CV as well.
The 'bodge' you see on the wirewound resistors is easily explained- and it isn't a bodge. Those are precision resistors, and they will have been made with a 'tail' of an inch or so of surplus resistance wire hanging out. During factory calibration, the soldered joint will have been moved up or down the tail to bring it into cal- and we are talking a tiny fraction of an ohm, serious precision! So credit where its due.... bodge indeed!!
And don't forget the broad arrow on the front...
In the video @ 15:45 it shows hand wound resistors.
The insulation is described in its tongue-twister name as "Double Cotton Covered Copper Wire". I use to work at AVO in the late 60s and it was my job to wind those. They were then painted with a lacquer to stop them unwinding.
What that in the Dover factory you worked?
@@rivets1001 I was an apprentice there after I left school in the late 60s. I spent my 7 years there in their "clean room" where they assembled the meters. That led me onto a career in electronics at the University of Kent at Canterbury. I stayed there 42 years until I retired 4 years ago. Did you work there?
I was crying like a baby when you show this device. Such a beautiful piece of history...
Dave, I'm an engineer from the early 1970s. Testers like that one were used to match transistors for push-pull circuits. There were easier ways to find bad transistors. But fancy testers like that were for matching parameters, often with thermal influences. In the 1970s, the industry moved to Tektronix oscilloscope-style transistor testers with built-in sawtooth generators for displaying the gain curves automatically.
Also, the Texas Instruments 7400-series logic I/Cs were not 1962-ish. Think more late 1960s. CMOS 4000-series were even later, circa 1972-ish if my memory serves. Transistors reigned supreme in the 1960s. Even inside Iron Man's suit. In the comics of the 1960s, everything in his suit was "transistor-powered". I'm sure Tony Stark would have had a tester like your Avocet.
Vacuum Tube shield + little metal tab = battery compartment. Gear!
It's a thing of beauty. Best teardown in a long while.
like to see it working
In the 60's information about specific transistors was more valued than now.
The spec sheets had a lot more parameters
Best birthday gift ever. An EEVBlog video :D Didn't get to watch it on my birthday sadly but hey, I still enjoy it either way :) I also vote to have you power that baby up and see how it does after 50+ years. Thanks for everything you do for us Dave. Been catching up on videos from the beginning, every day after work I watch a little more. Been waiting on my approval into the forum for ages though D: but watching your videos makes it worth the wait haha.
I know it's an old video, but if you still got this vintage transistor tester you should send it to Mr Carlson's Lab, he will have it working better than new in no time.
That what I thought when I saw this beautiful piece of kit.
23:14 these are diodes IR2E1 (International Rectifier) Type 2E1.
See service manual page 28, item no. 43
It is incredible to see that the rubber straps are still good ! I believe the yellow discs may be early diodes for International Rectifier.
Hi I started my apprenticeship in 1973 at a REME works and we had to do all wire looms with lacing cord. if you look closely you should not see any start or end knots. The start you can wind over itself and the end you form a loop and pull the end through the multiple wraps.
Those battery holders look like valve shield/retainers
I Thought the same thing!
have an old military radio with a lot of those shields
Makes sense - they made valve testers after all.
That thing was built the same year that I was "built"! I guess I'm old too...
I love it! built the same year I grauated from school.
Keep up these antique teardowns.
The arrow on the serial no. label indicates it was supplied to the military
I use to be on the production line for this instrument. A lot of the batches were made for the military. They had to be waterproof so we had a giant bath of water. They had a "Tyre Valve" for pressurising them before being submerged to detect any leaks i.e. bubbles.
Great tear down, absolute beauty! Definitely fix those caps and bring this majestic brick back to life.
That brought back some memories, Love to see it up and running. Thanks Dave, merry Christmas to you and your family.
Thanks for the video it is certainly well built.
The 2 small capacitors are meter protection diodes and the plugs in the battery compartment are held in place by bumpers on the main chassis
Lovely bit of kit. I have an AVO VCM163 tube (“valve”) analyzer, probably from the 70s. ACO was most famous for their tube analyzers. While the VCM163 tests vacuum tubes, it uses solid-state active parts inside. I think it’s the best of the service tube testers ever made.
Great bit of kit, Avo build quality is second to none.
I love the battery holders, they are actually screening cans for signal valves!
Please replace those leaky caps and fire it up, would bet it will work fine.
Love the old school tear downs Dave! What an excellent video!
How about 3D-printing some adapters for the AA batteries?
Beautiful thing! I really wish to thank someone who 50 years ago pulled the batteries out. What a mess it would be without that!
Great piece of gear Dave, I've used some of the old Transistor Testers in the USA vintage late '60's, early 70's but never one that old. Great video as always!
The "mid air" tie point at 16:00 is actually where they adjust the resistance value by melting the solder and sliding the wire to tweak the resistance.
I'd say that they would've just measured the resistance with a meter to determine the soldering point as it being tinned with solder would lower it's resistance over the tinned part of the wire, leaving much more to flap in the breeze, not really desirable.
MOD Record is the "Ministry Of Defence" here in the UK
and the number stenciled on the front of the case is a NATO Stock Number. Also the brass date plate has the MOD "Crows Foot" mark on it, it's the little arrow, every British Military Item tends to have this mark on them.
Like the way they have mounted the diode with spring leg, so it not will be physical stressed. (21:35)
The old oc transistor could be sensitive to 50/60 hz light if paint was scratched of.
Hit the nail on head perfectly at 11:30 when you said "Somebody really took pride in that".
They actually cared. We were actually building the product ourselves. Not by a 3rd world country. And when building a product that lasted a lifetime was a good thing.
It is always so refreshing to see these old-school well-built products. They represent a time when people actually gave a shit about something other than themselves. ☺
"Look at all those knobs" LOL. Seriously, keep the vids coming especially the retro/ vintage stuff.
Wow reminds me of my days in Communications and Electronics Section of the Brigade Headquarters, where we did in depth repair of everything from FM Radio Transceivers to Teletype machines back in 1970. We had devices designed in this exact manner so as to stand up to the conditions we encountered in Vietnam.
Gorgeous! That's as sexy as any piece of stereo/hifi gear I've ever seen. All those switches and knobs are gold. :)
Check out 21:20. Looks like the diode has a precision kink in it's lead for some reason? For a test probe perhaps?
Probably there to relieve any stresses (such as temperature expansion/contraction, etc.) on the diode body.
Ethan Poole Yup. Seen it on other kit of that vintage.
Definitely want to see a video of you powering it up and maybe seeing to the cap... Please pretty please
The size batteries that would fit in the u10 (D: ~20 mm; H: ~59 mm) holder would be:
"A" Cell (D: ~17 mm; H: ~50 mm) Usually Ni-Cd or Ni-MH
"B" Cell (D: ~21 mm; H: ~60 mm)
"AA" Cell (D: ~14 mm; H: ~50 mm)
Possibly a
"Sub-C" Cell (D: ~22 mm; H: ~43 mm) Ni-Cd or Ni-MH
"5/4Sub-C" Cell (D: ~22 mm; H: ~54 mm) Ni-Cd or Ni-MH
I work at Batteries and Bulbs in the US.
You can find the "B" Cell in 4.5V Lantern Batteries and the "No. 8"
The components shown at 23:20 are International Rectifier type 2E1 silicon diodes.
Man, I could turn those dials all day... kind of like popping bubble wrap.
I would love to see a repair / recapping of this piece of art. And it needn't be old age as such that caused the condenser (heh) to fail, it could be as simple as the meter having been sitting unused for quite some time and then someone coming along trying to power it up.
My electronics teacher taught us students to always ease things containing electrolytes coming from mothball status by gradually increasing the voltage over them, partly because failures tend not to be as catastrophic, partly because you in some instances could rejuvenate the condensers.
As to transistor testers, back when I was in electronics school, we didn't have transistor testers as such, but we did have standard test schematics we used together with the parts bins, a function generator and a scope (sometimes a diff probe) to breakboard a circuit so we could see all the relevant curves of a discrete.
Oh, and looking on my battery cheat-sheet, the dimensions of the R12 is ∅ 21.5
H 60, so a piece of plastic or cardboard tube around an AA/R6 and washers on the spring end should do the trick. With a quality Alkaline cell of course.
That loop in the germanium diode lead. Presumably to protected the glass housing from mechanical stress. Very nice detail.
I'd love to see this thing in action!
Try using C cells for the batteries, they're the same length as AA's after all.
Also, that dodgy cap should be an easy replacement, but IMO it deserves a high end cap, if only to keep the overall build quality at a similar level as when it was first built.
After all, if you don't respect your test equipment, it won't respect you.
...or something like that. Treat stuff right and it doesn't cause problems, that kind of thing.
IR2E1 - did you test to see if that is an old diode / rectifier or even a zener Dave? I did notice one on the schematic.
Just found a Mk. 2 that sold for £225.
never seen any electronics so old but looking so new!!! great!!! maybe it has time travelled!
Can't believe I've missed this video until now; I have the same tester which I was given back in about '84 because my school's electronics depertment were going to dispose of it. I also have the manual and the transistor data book that it originally came with, although AVO never sent my updated book when I returned the included post card! I believe the cells are A cells.
Back in the late 60's and early 70's, I used some AVO test equipment. I was working in TV broadcast engineering support and service.
wow Dave... you have a lot of cool stuff on this channel, but this might be the most beautiful of all. stunning build quality. funny how far we've come in electronics since then, but the days of such loving mechanical craftsmanship may be gone forever, at least outside of vehicles... I grew up in the 90s when most stuff had already gone plastic but I still feel drawn to old high end analog more than anything... combine this outside with the agilent RF meter inside and you got the ultimate gear quality
The great thing about AVO kit is that, even if it's completely buggered through the passage of time, it still feels, looks and smells like handmade quality kit :)
The AVO Model 8s were handmade by a production line of ladies hand soldering every joint. No PCBs anywhere. I know because I was an apprentice on that production line. I've never been so embarrassed due to the things the ladies talked about, you can imagine.
I would love to see this thing operating, I'd be curious to see it test modern transistors. Maybe do ten from the same batch and see what variances there are. Because people don't test them anymore, the variances could be quite large.
I so want that bit of kit. Bet it smells sweet too.
Would love to see it working! Also, you should do a video on those ebay $20 testers as well.
Awesome build quality. They even put a strain relief bend in that diode lead.
Dave, do the right thing, you owe it to your viewers. Go on...undo one end of any bad caps and tack in good ones, get 'er going!
Hi Dave. The arrow on the tag is a 'broad arrow' indicating property of the UK government (also used by other commonwealth countries, including Australia). The label inside probably doesn't stand for 'modification', but Ministry Of Defence.
Hi Dave,
I was thinking that D batteries would go in there??? Truly a thing of beauty, thanks for sharing!
This analyser is a fairly complicated piece of test equipment. It is very impressive!
How does the noise measurement work? At 1kHz there is mostly 1/f noise.
How can the rubber still be good? Magic rubber trees from Scotland?
Absolutely beautiful. There is no way this could be manufactured in the current market for any cheap price whatsoever,
Killer video Dave, makes me want to take apart some of the old dusty test gear in the back.
Amazing piece of kit. Did you ever get it going?
AWA is still around (went into administration earlier in 2014 but was acquired by the Cabrini group).
AVO later became part of Megger.
Hello greetings!
When repairing electronic equipment such as amplifiers, there are some defects such as microleakage in transistors that cannot be detected as shown in the video. The only way I can find them is with an analog multimeter from the 80's, like the Hioki AS100D or Sanwa 320x.
I'll give you an example:
The Hioki AS100D multimeter has a x100k scale that works with a 22.5v + 3v battery for a total voltage of 25.5v. Added to that, a super sensitive galvanometer that works with 9 microamps. Becoming an ultra effective instrument in detecting micro-leakage in semiconductor junctions.
How do you manage to detect these small leaks with the digital multimer? Or is there any other instrument that can do this?
Best 29 minutes I've spent today. Fantastic. Anyone know what happened to Mullard?
Subsumed into Philips years ago.
Graham Langley it was a Phillips subsidiary even during WW2. I had a relative who worked in the Mullard factory in the UK then.
Rob Fenwitch Didn't realise it went back that far, but the WP article says they formed a partnership in 1923, became a fully-owned subsidiary in 1927 and the Mullard name was dropped in 1988.
I did a tour of their Mitcham plant in the mid 70s. The place was half empty as valve production had all but ceased.
Vintage equipment just oozes awesome no matter how irrelevant.
CV2400 per google was a prototype transistor developed by the GPO in or around 1956;
This is the Post Office prototype transistor from about mid 1956.
Selected for Noise factor of 6dB.
Ge Junction Alloy. PNP
Have you tried replacing those busted caps? Hope it would work after 50 years and a quick fix.
Electrical Equipment of Australia LTD lasted 9 years before it was taken over in 1984 by Amalgamated Wireless Australasia Limited, or AWA. From everything i can find, they were a reasonably successful company. Which i guess you would have to be, to be taken over by the AWA in the mid 80's.
Their former offices at 75 Liverpool, is now a seafood restaurant. LOL, how times change.
Son of a Zombie
yes
www.awa.com.au/
bigbuckoramma Someone always knows!
Great video Dave, would love to see it powered up.
They were still using those when I joined Telecom New Zealand in 1985. You seem to have a fancier model than the one I got issued with.
hard to believe, that AVO was first made by a post office worker in London, and now AVO are part of megger, another british company that STILL make products in the UK, been past their dover factory a few times too! :D
The long code on the ID plate is its military part number or NATO ordering code (the up arrow signifies it's military equipment)
Dave. It would appear this bootiful instrument has a military past as it has the 'crowfoot' mark. The Z4 / ZDA 0929 is probably a military identification number. It was most likely contracted to AVO as a 'must have' at the time and remained in storage -unused!
Man I would love having an electronic's desk filled with this old equipment. Already got an oscilloscope and two vacuum tube voltmeters from the 70s made by Heathkit..
Would it hold C cells, and yes.... do it! I want to see it run!
joblessalex No, C cells don't fit.
Drats! The HD deceives again!
EEVblog
Maybe I am wrong, but there wasn't been any fundamental friday videos recently...? Are You not making them any more?
EEVblog But what about AA cells? The power consumption shouldn't be too large for a precision meter movement and low power high frequency generator.
Edit: I wrote before watching the video to the end. I would love to see it work too.
I have a friend called Plessy. I believe her Mom saw the name on the side of a truck and liked the sound of it.
Would like to see this up and running Dave.
YES! YES! WE DO WANT TO SEE IT WORKING!!!!
3:18 wow, the HFR really does it justice here
yes, the smell of old electronics is like the best thing ever!!!
When will the video of you using it be up ?
I've looked around about I can't find the tube tester my dad used to have. Similar suitcase construction. :)
the capacitor had the actual microfarad symbol printed on them, rather than MFD? I thought that wasn't a thing until the '90s
Just curious, what would a manufacturer of transistors use to test and specify their transistors in 1960? Would they have something like this?
TheAmmoniacal A proper curve tracer most likely. Although for production it would likely be production automated of course.
Power the beast up and have a play, btw, the connectors that were uncliped are most likely held secure against the body when the battery assembly is in position..
It has a Ministry of Defence pheon (arrow) on the label too, so definitely been used in government circles.
I have a container with over a hundred TO-5 packaged germanium transistors which came out of a 1960s-era Dymec computer-controlled integrating voltmeter. (Yes, computer-controlled, as in you could control the range selection and receive the output in BCD format over a serial cable). I pulled out each one and individually tested them with my Heathkit IT-18 transistor checker.
Transistor testers are useful if you do amplifier repair and need to match some transistors.
wow this is brilliant.. Would love to see it working
'Made in England' Do we make anything anymore?
The upward pointing arrow on the brass plate at 0:46, is that a WD (war department) mark? This might explain the build quality.
I could 'smell' the electronics through Dave's enthusiasm :-)
I collect all avo test gear love the build quality ,as you say
Please, make a video of that instrument working.
Power it up and more vintage teardowns please.
Hello Dave, that's a very interesting thing. I'd love to see it working. Why don't you make another video of the transistor analyser while testing a few standard components like the BC547? Greetings from Munich, Germany. Cyberfuzzy
Noise control knob may be put back on wrong by someone. Other than that, this specimen is nicely kept, probably a part of clean room equipment thus the lack of corrosion.
one word: beautiful!
Please try to get it working, it'll be great to see some vintage technology work after 50 years!
That is beautiful, phwoar!
Yes, I'd love to see it working.
Great piece of gear!
this reminds me of the test gear I used at AT&T years ago, back when Western Electric made everything, WECO made stuff to last a hundred years.
Nice to see the old design and high quality. These days a lot of plastics and low quality switches.
Fantastic quality
The little arrow on the ID plate means it was built for the MOD/War office (Ministry of Defense). So it would have been for military use originally.
The MOD record is probably ministry of defense too :)
I'd love to see it working! Those capacitors may not be bad, but the leaky one or two really need to be replaced.