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Item Condition: good for it age ( see picture)
Shipping Options: Pickup available but audition is not available.,Shipping is available at agreed cost.
Suburb or Town: Balwyn
State: Victoria
Payment Method: Cash or Bank transfer
Reason for selling: too complicate machine

Hi Stereonet member.

 I listing for sale Tube tester, This tester just bought not long ago. It turn on, I try to insert 12at7 test, it work but look like machine need service or i did wrong thing I am not sure The Machine so complicate Highly recommendation for professionals. If you know what is this, and how to used may be you are interesting. The machine will sale as is condition. They come with 160 page valve Data book, manual and working instruction book. 

Please Don’t Buy this machine if you are only test the valve.  Because this machine very complicate

Thank you for looking  
Photos:

9F4B4FC3-F717-4554-ADC6-C3A47F6E1F97.thumb.jpeg.a8d68456972075ca6f1a17f65a62189e.jpeg6F3136B1-7F86-45A4-BF14-D63961BD8DB0.thumb.jpeg.cd134d8b042e48c5acca8b5b4ea36171.jpeg0101B94B-7F77-4312-96C6-760B9338D493.thumb.jpeg.d82c1f3ebf4f10eced950f41d5813e0f.jpeg1807DD15-E28F-4C6F-901B-4A11693947DF.thumb.jpeg.33e9de2c44981c5a2f2780b874e8c531.jpeg6752AF35-EF80-4624-AFB0-1218901EACE6.thumb.jpeg.1db76fce6d78db1536681d52a7906b21.jpeg7724AE49-E6C7-45EE-A130-005A6031A549.thumb.jpeg.49d4d284a2a5bfa8e3ba3111f7c700b3.jpeg519FDEFB-8DFC-4992-BDD4-A5125B37EA2A.thumb.jpeg.b581ba65776465eaee1818edd130f8b5.jpeg

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That was comment from "palexsia" what he did before.   VCM163 the same family with this tester?

Newton McLaren have their phone number on there. Maybe call them and see if they have an instruction manual.😊 It would look cool on display as well. GLWTS

No thing involved with Ken Avo . I say that is my experienced when I learn to used the tester with John of hifiexchange and we hold the tube too long then we see smoke  come out . Ken  AVo Is good 

Some of the tubes you need to test fast or smoke come out of the tester . Incompetence peoples who not familiar with this tester need to aware .  I did a test with John of hifi exchange and that what’s happened because we are too slow , but we learned after that . 

Edited by palexsia
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34 minutes ago, McCvinyl said:

Newton McLaren have their phone number on there. Maybe call them and see if they have an instruction manual.😊

It would look cool on display as well. GLWTS

That company was apparently bought out by Lawrence and Hanson Ltd in 1974.

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One of the best valve testers if not the best on the planet and dead set easy to use if you understand the difference between mA and mA/V readings - totally agree with @Pigpen.

 

The former is all that is needed for a simple plate current measurement of a valve. There are a few youtube videos illustrating how to use this tester and other AVO valve testers, which operate on the same principle. The operating manual is written as an educational tool and easy to understand.

 

The only thing that goes in these is the galvanometer coil wire if bounced back and forth abruptly - yes -  it is sensitive and if bounced vigorously it burns out - not sure if smoke comes out though. 😁

 

There is a mod online that protects this part of the circuit.

 

David Crittle at Retrovox is your man for servicing these beauties.

 

GLWTS.

Edited by xlr8or
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Hi Ken, I can show You how to use the machine. Come to my place after the restriction is over. I have two of them and had been use it for many years. It is complicated to set up and use. It take time to set up and test each tube. Any thing wrong inside this machine can be fix but do not damage the VU meter, if the meter damage, the machine is in the bin. You can not get the right VU meter to replace it. It is specially made for AVO. The machine might need to calibrate to be accurate. To calibrate it use digital multimeter to check voltage on top of each pin for cathode, Heater, Heater plus, ground, A1 and A2 and D1 and D2 voltage. 

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38 minutes ago, tchye nguyen said:

Hi Ken, I can show You how to use the machine. Come to my place after the restriction is over. I have two of them and had been use it for many years. It is complicated to set up and use. It take time to set up and test each tube. Any thing wrong inside this machine can be fix but do not damage the VU meter, if the meter damage, the machine is in the bin. You can not get the right VU meter to replace it. It is specially made for AVO. The machine might need to calibrate to be accurate. To calibrate it use digital multimeter to check voltage on top of each pin for cathode, Heater, Heater plus, ground, A1 and A2 and D1 and D2 voltage. 

Can you show example for 6ca7 setting10457E99-305A-4037-B1B6-98719B8FF460.thumb.jpeg.4da2965da56fe5c483979debc826503c.jpeg

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The selector switch 126 540 310.

Heater voltage 6.3v

Negative grid voltage 14.5v

Anode voltage 250v

Screen voltage 250v

mA/V 8.5

Factory requirement for a new 6CA7 tube is 57. If the test shown Your 6CA7 is 57 it is a pass if it is higher then 57 it is very strong and if it is under 57 it is low. You then have other test for gas, Cathode/ heater insulation test. short circuit test, test hot test cold. 

Note: D1 and D2 is for testing rectifier tube.

 

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1 hour ago, tchye nguyen said:

The selector switch 126 540 310.

Heater voltage 6.3v

Negative grid voltage 14.5v

Anode voltage 250v

Screen voltage 250v

mA/V 8.5

Factory requirement for a new 6CA7 tube is 57. If the test shown Your 6CA7 is 57 it is a pass if it is higher then 57 it is very strong and if it is under 57 it is low. You then have other test for gas, Cathode/ heater insulation test. short circuit test, test hot test cold. 

Note: D1 and D2 is for testing rectifier tube.

 

image.thumb.jpg.8f36516495b449622d320a2b662e841b.jpg

Edited by QT- kWang
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2 minutes ago, QT- kWang said:

That is Reading first set up follow your number value instructions, look in pictures is this right?

All settings look right.

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1 hour ago, tchye nguyen said:

The selector switch 126 540 310.

Heater voltage 6.3v

Negative grid voltage 14.5v

Anode voltage 250v

Screen voltage 250v

mA/V 8.5

Factory requirement for a new 6CA7 tube is 57. If the test shown Your 6CA7 is 57 it is a pass if it is higher then 57 it is very strong and if it is under 57 it is low. You then have other test for gas, Cathode/ heater insulation test. short circuit test, test hot test cold. 

Note: D1 and D2 is for testing rectifier tube.

 

Which column is  "Anode voltage"

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On 11/09/2020 at 3:43 PM, palexsia said:

Some of the tubes you need to test fast or smoke come out of the tester . Incompetence peoples who not familiar with this tester need to aware .  I did a test with John of hifi exchange and that what’s happened because we are too slow , but we learned after that . 

Mate if you made smoke come out of the tester? You've done something seriously wrong. They have an Anode overload protection circuit. If it's smoked, something is damaged and it will need a full check over. In perfect working condition it may be worth 1800 bucks, but from the look and your description of what happened???

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8 minutes ago, Graywulf said:

Mate if you made smoke come out of the tester? You've done something seriously wrong. They have an Anode overload protection circuit. If it's smoked, something is damaged and it will need a full check over. In perfect working condition it may be worth 1800 bucks, but from the look and your description of what happened???

Don't mistake this one smoke not come out!!!!!!!!

Edited by QT- kWang
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1 minute ago, QT- kWang said:

Don't mistake this one smoke is come out!!!!!!!!

" I did a test with John of hifi exchange and that what’s happened because we are too slow , but we learned after that . "

They were your words.... smoke came out of it.   Avo's (apart from that meter) are usually pretty bullet proof, I love my VCM 163

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5 minutes ago, Graywulf said:

" I did a test with John of hifi exchange and that what’s happened because we are too slow , but we learned after that . "

They were your words.... smoke came out of it.   Avo's (apart from that meter) are usually pretty bullet proof, I love my VCM 163

That was comment from "palexsia" what he did before.

 

VCM163 the same family with this tester?

Edited by QT- kWang
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Just now, Graywulf said:

" I did a test with John of hifi exchange and that what’s happened because we are too slow , but we learned after that . "

They were your words.... smoke came out of it.   Avo's (apart from that meter) are usually pretty bullet proof, I love my VCM 163

I think the issue here is definitely with the galvanometer and it sounds like it's overheating. As @tchye nguyen mentioned if you burn out the coil there is no replacement meter. It will need to be sent to Jacmusic to be reconditioned and the price is not cheap. I'm pretty sure this is happening when the mA/V readings are being taken.

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7 minutes ago, QT- kWang said:

If it too strong !

What can i do next step??????

Nothing further needs to be done. Write down the value and test the next valve. If you want to also take the mA/V reading you need to use the dial on the right to get a full deflection value of 1mA/V. I would suggest only doing this measurement after you have measured several mA values and you feel comfortable using the unit.

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2 minutes ago, QT- kWang said:

That was comment from "palexsia" what he did before.

 

VCM163 the same family with this tester?

the 163 was Avo's last tester. some would say the 'ultimate Avo'? There are other better 'laboratory testers' but extremely expensive. The real advantage of the 163 over the mk4, is it does not require the 'backing off' and Mu/milliamps are displayed simultaneously on two different meters. Otherwise really, the Mk4 is probably as good.

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1 minute ago, treuben said:

It seems to me that what they are saying is that the meter for sale has not emitted smoke and that the second person to comment was speaking about their own experiences with a similar tester. Would that be correct @palexsia?

 I only say the experience i had with John of hifi exchange . You are corrected Treuben .

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15 minutes ago, xlr8or said:

Nothing further needs to be done. Write down the value and test the next valve. If you want to also take the mA/V reading you need to use the dial on the right to get a full deflection value of 1mA/V. I would suggest only doing this measurement after you have measured several mA values and you feel comfortable using the unit.

Thank you ! The tester so complicate therefore i listed it on the market, but now see many members show me something I feel like exciting now

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@QT- kWang please look here:

 

EL34 test on AVO Mk3 Valve tester. - YouTube

 

I think the value of 57mA in the databook for a new 6CA7 valve is incorrect - it should be 75mA. Your valve just comes in under. Please use the EL34 setting to test the valve.

 

If you need any further help please PM me as we are in the wrong forum to be discussing this further. 👍👍👍

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30 minutes ago, Graywulf said:

" I did a test with John of hifi exchange and that what’s happened because we are too slow , but we learned after that . "

They were your words.... smoke came out of it.   Avo's (apart from that meter) are usually pretty bullet proof, I love my VCM 163

 

19 minutes ago, Graywulf said:

the 163 was Avo's last tester. some would say the 'ultimate Avo'? There are other better 'laboratory testers' but extremely expensive. The real advantage of the 163 over the mk4, is it does not require the 'backing off' and Mu/milliamps are displayed simultaneously on two different meters. Otherwise really, the Mk4 is probably as good.

No thing involved with Ken Avo . I say that is my experienced when I learn to used the tester with John of hifiexchange and we hold the tube too long then we see smoke  come out . Ken  AVo Is good 

Edited by palexsia
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No matter how long the tube is on, no smoke should ever come out of anything!  If a tube has a fault, the tester will cut out.

 

You should always warm the tube up for like 40 -60 seconds before you check C/H shorts, and only then switch to TEST.  Leave it on TEST for like 15 seconds to level out, take reading and then switch to GAS.  Then switch it back to off.

 

Do not walk away and leave tube on TEST for longer than needed.  In TEST, the tube is being run flat out, like holding an engine in the redline, and you will prematurely wear out the tube.  Don't believe me - try it!

 

A 163 is a much friendlier  machine to use, but you cannot directly test DHT tubes like 2A3, 300B, 10Y etc.

 

Please keep in mind, these testers are 50 years and older and if they are not calibrated recently - then the test results can be way off accurate.

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25 minutes ago, xlr8or said:

@QT- kWang please look here:

 

EL34 test on AVO Mk3 Valve tester. - YouTube

 

I think the value of 57mA in the databook for a new 6CA7 valve is incorrect - it should be 75mA. Your valve just comes in under. Please use the EL34 setting to test the valve.

 

If you need any further help please PM me as we are in the wrong forum to be discussing this further. 👍👍👍

Yes, Look right! because i tested all my el34 valves, any of them over 70 mA abit

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19 minutes ago, Red MacKay said:

No matter how long the tube is on, no smoke should ever come out of anything!  If a tube has a fault, the tester will cut out.

 

You should always warm the tube up for like 40 -60 seconds before you check C/H shorts, and only then switch to TEST.  Leave it on TEST for like 15 seconds to level out, take reading and then switch to GAS.  Then switch it back to off.

 

Do not walk away and leave tube on TEST for longer than needed.  In TEST, the tube is being run flat out, like holding an engine in the redline, and you will prematurely wear out the tube.  Don't believe me - try it!

 

A 163 is a much friendlier  machine to use, but you cannot directly test DHT tubes like 2A3, 300B, 10Y etc.

 

Please keep in mind, these testers are 50 years and older and if they are not calibrated recently - then the test results can be way off accurate.

Great information for me to learned  Thanks

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Hi Ken, this is a good tube being 70ma. Your machine working fine. Take Your time testing the valve. first set it up correctly, double check all the switch. then start tesing cold for short, open. then switch to testing hot. test for short and open then switch to cathode/ heater insulation test  to check high resistance. this test must shown high cathode/heater insulation . if it is low with out put tube it is allow up to 15 mega ohm. If it is 9 pin tube eg 12ax7 it has to be higher than 25 mega ohm, under that your tube is a low insulation between cathode and heater, your tube not to be use as it is microphonic and can be short cct.  than switch to gas if there is gas tube not to be use. If smoke come out  from the tube tester it mean the VU meter gone. Your VU meter is fine, Your machine working ok and You dont have to test fast. Some tube if never been use ( new old stock)  for a long time might need to wait for it to warm up.. If You want to calibrate it You need a multimeter. The only issue with AVO machine is when the VU meter damage, smoke will come out when VU meter burn. 

Note: when testing a tube if you see meter is motor boating, it can be tube not use for many years (NOS tube ) it need  a litle time to heat up. if it keep motor boating it might be the tube pin is corrode oxydide and not make good contact, take it out clean the pin. plug it back in and test it. Like Red have said this machine will need calibrate as result might be way from factory seting. 

Dont leave tube in the machine for long time and do other thing. There will be no smoke come out from machine but You do worn out Your tube. AVO 163 is the last model and it is more modern machine.  I have 2 of them. One with VU meter faulty and had been looking for VU meter  ladt 4 and half year, hope in this forum any one had one spare working can sale to Me.

Edited by tchye nguyen
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Something to be aware of is that there are errors in some of the AVO Valve data books, I do recall seeing the 57mA rating in one of the later books for the EL34 as well as incorrect tumbler position settings for some reasonably common valves.

It may pay to download a couple of different versions to cross reference

mm.

Edited by MosfetMainac
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11 minutes ago, MosfetMainac said:

Something to be aware of is that there are errors in some of the AVO Valve data books, I do recall seeing the 57mA rating in one of the later books for the EL34 as well as incorrect tumbler position settings for some reasonably common valves.

It may pay to download a couple of different versions to cross reference

mm.

I agree.  Mohan used to test el34s at higher volts that the book as he believed it didn't give realistic measurements of the tube at lower volts.  Clever man Mohan.

 

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15 hours ago, xlr8or said:

Nothing further needs to be done. Write down the value and test the next valve. If you want to also take the mA/V reading you need to use the dial on the right to get a full deflection value of 1mA/V. I would suggest only doing this measurement after you have measured several mA values and you feel comfortable using the unit.

Great, Thanks !  I try to do

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11 hours ago, tchye nguyen said:

Hi Ken, this is a good tube being 70ma. Your machine working fine. Take Your time testing the valve. first set it up correctly, double check all the switch. then start tesing cold for short, open. then switch to testing hot. test for short and open then switch to cathode/ heater insulation test  to check high resistance. this test must shown high cathode/heater insulation . if it is low with out put tube it is allow up to 15 mega ohm. If it is 9 pin tube eg 12ax7 it has to be higher than 25 mega ohm, under that your tube is a low insulation between cathode and heater, your tube not to be use as it is microphonic and can be short cct.  than switch to gas if there is gas tube not to be use. If smoke come out  from the tube tester it mean the VU meter gone. Your VU meter is fine, Your machine working ok and You dont have to test fast. Some tube if never been use ( new old stock)  for a long time might need to wait for it to warm up.. If You want to calibrate it You need a multimeter. The only issue with AVO machine is when the VU meter damage, smoke will come out when VU meter burn. 

Note: when testing a tube if you see meter is motor boating, it can be tube not use for many years (NOS tube ) it need  a litle time to heat up. if it keep motor boating it might be the tube pin is corrode oxydide and not make good contact, take it out clean the pin. plug it back in and test it. Like Red have said this machine will need calibrate as result might be way from factory seting. 

Dont leave tube in the machine for long time and do other thing. There will be no smoke come out from machine but You do worn out Your tube. AVO 163 is the last model and it is more modern machine.  I have 2 of them. One with VU meter faulty and had been looking for VU meter  ladt 4 and half year, hope in this forum any one had one spare working can sale to Me.

Tony please tell me ‘la  mA’  show 57 in column what it mean? 

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Ia = Anode Current

mA = Milliamperes 

Anode current is the reading you measure after checking for shorts etc., normally it takes a minute or two for the tube to warm up and stabilise

Gm = Mutual Conductance, this is measured after backing off the meter dial to zero.

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